ClangFormat: apply to source, most of intern

Apply clang format as proposed in T53211.

For details on usage and instructions for migrating branches
without conflicts, see:

https://wiki.blender.org/wiki/Tools/ClangFormat

9 files changed, 4793 insertions, 4270 deletions

diff --git a/source/blender/physics/BPH_mass_spring.h b/source/blender/physics/BPH_mass_spring.h
index 56743b4867a..9666f9ba9ed 100644
--- a/source/blender/physics/BPH_mass_spring.h
+++ b/source/blender/physics/BPH_mass_spring.h
@@ -36,10 +36,10 @@ struct Object;
 struct VoxelData;
 
 typedef enum eMassSpringSolverStatus {
-	BPH_SOLVER_SUCCESS              = (1 << 0),
-	BPH_SOLVER_NUMERICAL_ISSUE      = (1 << 1),
-	BPH_SOLVER_NO_CONVERGENCE       = (1 << 2),
-	BPH_SOLVER_INVALID_INPUT        = (1 << 3),
+  BPH_SOLVER_SUCCESS = (1 << 0),
+  BPH_SOLVER_NUMERICAL_ISSUE = (1 << 1),
+  BPH_SOLVER_NO_CONVERGENCE = (1 << 2),
+  BPH_SOLVER_INVALID_INPUT = (1 << 3),
 } eMassSpringSolverStatus;
 
 struct Implicit_Data *BPH_mass_spring_solver_create(int numverts, int numsprings);
@@ -48,7 +48,11 @@ int BPH_mass_spring_solver_numvert(struct Implicit_Data *id);
 
 int BPH_cloth_solver_init(struct Object *ob, struct ClothModifierData *clmd);
 void BPH_cloth_solver_free(struct ClothModifierData *clmd);
-int BPH_cloth_solve(struct Depsgraph *depsgraph, struct Object *ob, float frame, struct ClothModifierData *clmd, struct ListBase *effectors);
+int BPH_cloth_solve(struct Depsgraph *depsgraph,
+                    struct Object *ob,
+                    float frame,
+                    struct ClothModifierData *clmd,
+                    struct ListBase *effectors);
 void BKE_cloth_solver_set_positions(struct ClothModifierData *clmd);
 
 #ifdef __cplusplus
diff --git a/source/blender/physics/CMakeLists.txt b/source/blender/physics/CMakeLists.txt
index 0a991bf2929..e40d1de666b 100644
--- a/source/blender/physics/CMakeLists.txt
+++ b/source/blender/physics/CMakeLists.txt
@@ -19,30 +19,30 @@
 # ***** END GPL LICENSE BLOCK *****
 
 set(INC
-	.
-	intern
-	../blenlib
-	../blenkernel
-	../depsgraph
-	../imbuf
-	../makesdna
-	../../../intern/guardedalloc
+  .
+  intern
+  ../blenlib
+  ../blenkernel
+  ../depsgraph
+  ../imbuf
+  ../makesdna
+  ../../../intern/guardedalloc
 )
 
 set(INC_SYS
-	${EIGEN3_INCLUDE_DIRS}
+  ${EIGEN3_INCLUDE_DIRS}
 )
 
 set(SRC
-	intern/BPH_mass_spring.cpp
-	intern/ConstrainedConjugateGradient.h
-	intern/eigen_utils.h
-	intern/hair_volume.cpp
-	intern/implicit.h
-	intern/implicit_blender.c
-	intern/implicit_eigen.cpp
+  intern/BPH_mass_spring.cpp
+  intern/ConstrainedConjugateGradient.h
+  intern/eigen_utils.h
+  intern/hair_volume.cpp
+  intern/implicit.h
+  intern/implicit_blender.c
+  intern/implicit_eigen.cpp
 
-	BPH_mass_spring.h
+  BPH_mass_spring.h
 )
 
 set(LIB
diff --git a/source/blender/physics/intern/BPH_mass_spring.cpp b/source/blender/physics/intern/BPH_mass_spring.cpp
index 1c78a0728b2..fa204e8a7f9 100644
--- a/source/blender/physics/intern/BPH_mass_spring.cpp
+++ b/source/blender/physics/intern/BPH_mass_spring.cpp
@@ -53,549 +53,602 @@ static float I3[3][3] = {{1.0, 0.0, 0.0}, {0.0, 1.0, 0.0}, {0.0, 0.0, 1.0}};
  */
 static int cloth_count_nondiag_blocks(Cloth *cloth)
 {
-	LinkNode *link;
-	int nondiag = 0;
-
-	for (link = cloth->springs; link; link = link->next) {
-		ClothSpring *spring = (ClothSpring *)link->link;
-		switch (spring->type) {
-			case CLOTH_SPRING_TYPE_BENDING_HAIR:
-				/* angular bending combines 3 vertices */
-				nondiag += 3;
-				break;
-
-			default:
-				/* all other springs depend on 2 vertices only */
-				nondiag += 1;
-				break;
-		}
-	}
-
-	return nondiag;
+  LinkNode *link;
+  int nondiag = 0;
+
+  for (link = cloth->springs; link; link = link->next) {
+    ClothSpring *spring = (ClothSpring *)link->link;
+    switch (spring->type) {
+      case CLOTH_SPRING_TYPE_BENDING_HAIR:
+        /* angular bending combines 3 vertices */
+        nondiag += 3;
+        break;
+
+      default:
+        /* all other springs depend on 2 vertices only */
+        nondiag += 1;
+        break;
+    }
+  }
+
+  return nondiag;
 }
 
 int BPH_cloth_solver_init(Object *UNUSED(ob), ClothModifierData *clmd)
 {
-	Cloth *cloth = clmd->clothObject;
-	ClothVertex *verts = cloth->verts;
-	const float ZERO[3] = {0.0f, 0.0f, 0.0f};
-	Implicit_Data *id;
-	unsigned int i, nondiag;
+  Cloth *cloth = clmd->clothObject;
+  ClothVertex *verts = cloth->verts;
+  const float ZERO[3] = {0.0f, 0.0f, 0.0f};
+  Implicit_Data *id;
+  unsigned int i, nondiag;
 
-	nondiag = cloth_count_nondiag_blocks(cloth);
-	cloth->implicit = id = BPH_mass_spring_solver_create(cloth->mvert_num, nondiag);
+  nondiag = cloth_count_nondiag_blocks(cloth);
+  cloth->implicit = id = BPH_mass_spring_solver_create(cloth->mvert_num, nondiag);
 
-	for (i = 0; i < cloth->mvert_num; i++) {
-		BPH_mass_spring_set_vertex_mass(id, i, verts[i].mass);
-	}
+  for (i = 0; i < cloth->mvert_num; i++) {
+    BPH_mass_spring_set_vertex_mass(id, i, verts[i].mass);
+  }
 
-	for (i = 0; i < cloth->mvert_num; i++) {
-		BPH_mass_spring_set_motion_state(id, i, verts[i].x, ZERO);
-	}
+  for (i = 0; i < cloth->mvert_num; i++) {
+    BPH_mass_spring_set_motion_state(id, i, verts[i].x, ZERO);
+  }
 
-	return 1;
+  return 1;
 }
 
 void BPH_cloth_solver_free(ClothModifierData *clmd)
 {
-	Cloth *cloth = clmd->clothObject;
+  Cloth *cloth = clmd->clothObject;
 
-	if (cloth->implicit) {
-		BPH_mass_spring_solver_free(cloth->implicit);
-		cloth->implicit = NULL;
-	}
+  if (cloth->implicit) {
+    BPH_mass_spring_solver_free(cloth->implicit);
+    cloth->implicit = NULL;
+  }
 }
 
 void BKE_cloth_solver_set_positions(ClothModifierData *clmd)
 {
-	Cloth *cloth = clmd->clothObject;
-	ClothVertex *verts = cloth->verts;
-	unsigned int mvert_num = cloth->mvert_num, i;
-	ClothHairData *cloth_hairdata = clmd->hairdata;
-	Implicit_Data *id = cloth->implicit;
-
-	for (i = 0; i < mvert_num; i++) {
-		if (cloth_hairdata) {
-			ClothHairData *root = &cloth_hairdata[i];
-			BPH_mass_spring_set_rest_transform(id, i, root->rot);
-		}
-		else
-			BPH_mass_spring_set_rest_transform(id, i, I3);
-
-		BPH_mass_spring_set_motion_state(id, i, verts[i].x, verts[i].v);
-	}
+  Cloth *cloth = clmd->clothObject;
+  ClothVertex *verts = cloth->verts;
+  unsigned int mvert_num = cloth->mvert_num, i;
+  ClothHairData *cloth_hairdata = clmd->hairdata;
+  Implicit_Data *id = cloth->implicit;
+
+  for (i = 0; i < mvert_num; i++) {
+    if (cloth_hairdata) {
+      ClothHairData *root = &cloth_hairdata[i];
+      BPH_mass_spring_set_rest_transform(id, i, root->rot);
+    }
+    else
+      BPH_mass_spring_set_rest_transform(id, i, I3);
+
+    BPH_mass_spring_set_motion_state(id, i, verts[i].x, verts[i].v);
+  }
 }
 
-static bool collision_response(ClothModifierData *clmd, CollisionModifierData *collmd, CollPair *collpair, float dt, float restitution, float r_impulse[3])
+static bool collision_response(ClothModifierData *clmd,
+                               CollisionModifierData *collmd,
+                               CollPair *collpair,
+                               float dt,
+                               float restitution,
+                               float r_impulse[3])
 {
-	Cloth *cloth = clmd->clothObject;
-	int index = collpair->ap1;
-	bool result = false;
-
-	float v1[3], v2_old[3], v2_new[3], v_rel_old[3], v_rel_new[3];
-	float epsilon2 = BLI_bvhtree_get_epsilon(collmd->bvhtree);
-
-	float margin_distance = (float)collpair->distance - epsilon2;
-	float mag_v_rel;
-
-	zero_v3(r_impulse);
-
-	if (margin_distance > 0.0f)
-		return false; /* XXX tested before already? */
-
-	/* only handle static collisions here */
-	if (collpair->flag & COLLISION_IN_FUTURE)
-		return false;
-
-	/* velocity */
-	copy_v3_v3(v1, cloth->verts[index].v);
-	collision_get_collider_velocity(v2_old, v2_new, collmd, collpair);
-	/* relative velocity = velocity of the cloth point relative to the collider */
-	sub_v3_v3v3(v_rel_old, v1, v2_old);
-	sub_v3_v3v3(v_rel_new, v1, v2_new);
-	/* normal component of the relative velocity */
-	mag_v_rel = dot_v3v3(v_rel_old, collpair->normal);
-
-	/* only valid when moving toward the collider */
-	if (mag_v_rel < -ALMOST_ZERO) {
-		float v_nor_old, v_nor_new;
-		float v_tan_old[3], v_tan_new[3];
-		float bounce, repulse;
-
-		/* Collision response based on
-		 * "Simulating Complex Hair with Robust Collision Handling" (Choe, Choi, Ko, ACM SIGGRAPH 2005)
-		 * http://graphics.snu.ac.kr/publications/2005-choe-HairSim/Choe_2005_SCA.pdf
-		 */
-
-		v_nor_old = mag_v_rel;
-		v_nor_new = dot_v3v3(v_rel_new, collpair->normal);
-
-		madd_v3_v3v3fl(v_tan_old, v_rel_old, collpair->normal, -v_nor_old);
-		madd_v3_v3v3fl(v_tan_new, v_rel_new, collpair->normal, -v_nor_new);
-
-		bounce = -v_nor_old * restitution;
-
-		repulse = -margin_distance / dt; /* base repulsion velocity in normal direction */
-		/* XXX this clamping factor is quite arbitrary ...
-		 * not sure if there is a more scientific approach, but seems to give good results
-		 */
-		CLAMP(repulse, 0.0f, 4.0f * bounce);
-
-		if (margin_distance < -epsilon2) {
-			mul_v3_v3fl(r_impulse, collpair->normal, max_ff(repulse, bounce) - v_nor_new);
-		}
-		else {
-			bounce = 0.0f;
-			mul_v3_v3fl(r_impulse, collpair->normal, repulse - v_nor_new);
-		}
-
-		result = true;
-	}
-
-	return result;
+  Cloth *cloth = clmd->clothObject;
+  int index = collpair->ap1;
+  bool result = false;
+
+  float v1[3], v2_old[3], v2_new[3], v_rel_old[3], v_rel_new[3];
+  float epsilon2 = BLI_bvhtree_get_epsilon(collmd->bvhtree);
+
+  float margin_distance = (float)collpair->distance - epsilon2;
+  float mag_v_rel;
+
+  zero_v3(r_impulse);
+
+  if (margin_distance > 0.0f)
+    return false; /* XXX tested before already? */
+
+  /* only handle static collisions here */
+  if (collpair->flag & COLLISION_IN_FUTURE)
+    return false;
+
+  /* velocity */
+  copy_v3_v3(v1, cloth->verts[index].v);
+  collision_get_collider_velocity(v2_old, v2_new, collmd, collpair);
+  /* relative velocity = velocity of the cloth point relative to the collider */
+  sub_v3_v3v3(v_rel_old, v1, v2_old);
+  sub_v3_v3v3(v_rel_new, v1, v2_new);
+  /* normal component of the relative velocity */
+  mag_v_rel = dot_v3v3(v_rel_old, collpair->normal);
+
+  /* only valid when moving toward the collider */
+  if (mag_v_rel < -ALMOST_ZERO) {
+    float v_nor_old, v_nor_new;
+    float v_tan_old[3], v_tan_new[3];
+    float bounce, repulse;
+
+    /* Collision response based on
+     * "Simulating Complex Hair with Robust Collision Handling" (Choe, Choi, Ko, ACM SIGGRAPH 2005)
+     * http://graphics.snu.ac.kr/publications/2005-choe-HairSim/Choe_2005_SCA.pdf
+     */
+
+    v_nor_old = mag_v_rel;
+    v_nor_new = dot_v3v3(v_rel_new, collpair->normal);
+
+    madd_v3_v3v3fl(v_tan_old, v_rel_old, collpair->normal, -v_nor_old);
+    madd_v3_v3v3fl(v_tan_new, v_rel_new, collpair->normal, -v_nor_new);
+
+    bounce = -v_nor_old * restitution;
+
+    repulse = -margin_distance / dt; /* base repulsion velocity in normal direction */
+    /* XXX this clamping factor is quite arbitrary ...
+     * not sure if there is a more scientific approach, but seems to give good results
+     */
+    CLAMP(repulse, 0.0f, 4.0f * bounce);
+
+    if (margin_distance < -epsilon2) {
+      mul_v3_v3fl(r_impulse, collpair->normal, max_ff(repulse, bounce) - v_nor_new);
+    }
+    else {
+      bounce = 0.0f;
+      mul_v3_v3fl(r_impulse, collpair->normal, repulse - v_nor_new);
+    }
+
+    result = true;
+  }
+
+  return result;
 }
 
 /* Init constraint matrix
  * This is part of the modified CG method suggested by Baraff/Witkin in
  * "Large Steps in Cloth Simulation" (Siggraph 1998)
  */
-static void cloth_setup_constraints(ClothModifierData *clmd, ColliderContacts *contacts, int totcolliders, float dt)
+static void cloth_setup_constraints(ClothModifierData *clmd,
+                                    ColliderContacts *contacts,
+                                    int totcolliders,
+                                    float dt)
 {
-	Cloth *cloth = clmd->clothObject;
-	Implicit_Data *data = cloth->implicit;
-	ClothVertex *verts = cloth->verts;
-	int mvert_num = cloth->mvert_num;
-	int i, j, v;
-
-	const float ZERO[3] = {0.0f, 0.0f, 0.0f};
-
-	BPH_mass_spring_clear_constraints(data);
-
-	for (v = 0; v < mvert_num; v++) {
-		if (verts[v].flags & CLOTH_VERT_FLAG_PINNED) {
-			/* pinned vertex constraints */
-			BPH_mass_spring_add_constraint_ndof0(data, v, ZERO); /* velocity is defined externally */
-		}
-
-		verts[v].impulse_count = 0;
-	}
-
-	for (i = 0; i < totcolliders; ++i) {
-		ColliderContacts *ct = &contacts[i];
-		for (j = 0; j < ct->totcollisions; ++j) {
-			CollPair *collpair = &ct->collisions[j];
-//			float restitution = (1.0f - clmd->coll_parms->damping) * (1.0f - ct->ob->pd->pdef_sbdamp);
-			float restitution = 0.0f;
-			int v = collpair->face1;
-			float impulse[3];
-
-			/* pinned verts handled separately */
-			if (verts[v].flags & CLOTH_VERT_FLAG_PINNED)
-				continue;
-
-			/* XXX cheap way of avoiding instability from multiple collisions in the same step
-			 * this should eventually be supported ...
-			 */
-			if (verts[v].impulse_count > 0)
-				continue;
-
-			/* calculate collision response */
-			if (!collision_response(clmd, ct->collmd, collpair, dt, restitution, impulse))
-				continue;
-
-			BPH_mass_spring_add_constraint_ndof2(data, v, collpair->normal, impulse);
-			++verts[v].impulse_count;
-		}
-	}
+  Cloth *cloth = clmd->clothObject;
+  Implicit_Data *data = cloth->implicit;
+  ClothVertex *verts = cloth->verts;
+  int mvert_num = cloth->mvert_num;
+  int i, j, v;
+
+  const float ZERO[3] = {0.0f, 0.0f, 0.0f};
+
+  BPH_mass_spring_clear_constraints(data);
+
+  for (v = 0; v < mvert_num; v++) {
+    if (verts[v].flags & CLOTH_VERT_FLAG_PINNED) {
+      /* pinned vertex constraints */
+      BPH_mass_spring_add_constraint_ndof0(data, v, ZERO); /* velocity is defined externally */
+    }
+
+    verts[v].impulse_count = 0;
+  }
+
+  for (i = 0; i < totcolliders; ++i) {
+    ColliderContacts *ct = &contacts[i];
+    for (j = 0; j < ct->totcollisions; ++j) {
+      CollPair *collpair = &ct->collisions[j];
+      //          float restitution = (1.0f - clmd->coll_parms->damping) * (1.0f - ct->ob->pd->pdef_sbdamp);
+      float restitution = 0.0f;
+      int v = collpair->face1;
+      float impulse[3];
+
+      /* pinned verts handled separately */
+      if (verts[v].flags & CLOTH_VERT_FLAG_PINNED)
+        continue;
+
+      /* XXX cheap way of avoiding instability from multiple collisions in the same step
+       * this should eventually be supported ...
+       */
+      if (verts[v].impulse_count > 0)
+        continue;
+
+      /* calculate collision response */
+      if (!collision_response(clmd, ct->collmd, collpair, dt, restitution, impulse))
+        continue;
+
+      BPH_mass_spring_add_constraint_ndof2(data, v, collpair->normal, impulse);
+      ++verts[v].impulse_count;
+    }
+  }
 }
 
 /* computes where the cloth would be if it were subject to perfectly stiff edges
  * (edge distance constraints) in a lagrangian solver.  then add forces to help
  * guide the implicit solver to that state.  this function is called after
  * collisions*/
-static int UNUSED_FUNCTION(cloth_calc_helper_forces)(Object *UNUSED(ob), ClothModifierData *clmd, float (*initial_cos)[3], float UNUSED(step), float dt)
+static int UNUSED_FUNCTION(cloth_calc_helper_forces)(Object *UNUSED(ob),
+                                                     ClothModifierData *clmd,
+                                                     float (*initial_cos)[3],
+                                                     float UNUSED(step),
+                                                     float dt)
 {
-	Cloth *cloth = clmd->clothObject;
-	float(*cos)[3] = (float(*)[3])MEM_callocN(sizeof(float[3]) * cloth->mvert_num, "cos cloth_calc_helper_forces");
-	float *masses = (float *)MEM_callocN(sizeof(float) * cloth->mvert_num, "cos cloth_calc_helper_forces");
-	LinkNode *node;
-	ClothSpring *spring;
-	ClothVertex *cv;
-	int i, steps;
-
-	cv = cloth->verts;
-	for (i = 0; i < cloth->mvert_num; i++, cv++) {
-		copy_v3_v3(cos[i], cv->tx);
-
-		if (cv->goal == 1.0f || len_squared_v3v3(initial_cos[i], cv->tx) != 0.0f) {
-			masses[i] = 1e+10;
-		}
-		else {
-			masses[i] = cv->mass;
-		}
-	}
-
-	steps = 55;
-	for (i = 0; i < steps; i++) {
-		for (node = cloth->springs; node; node = node->next) {
-			/* ClothVertex *cv1, *cv2; */ /* UNUSED */
-			int v1, v2;
-			float len, c, l, vec[3];
-
-			spring = (ClothSpring *)node->link;
-			if (spring->type != CLOTH_SPRING_TYPE_STRUCTURAL && spring->type != CLOTH_SPRING_TYPE_SHEAR)
-				continue;
-
-			v1 = spring->ij; v2 = spring->kl;
-			/* cv1 = cloth->verts + v1; */ /* UNUSED */
-			/* cv2 = cloth->verts + v2; */ /* UNUSED */
-			len = len_v3v3(cos[v1], cos[v2]);
-
-			sub_v3_v3v3(vec, cos[v1], cos[v2]);
-			normalize_v3(vec);
-
-			c = (len - spring->restlen);
-			if (c == 0.0f)
-				continue;
-
-			l = c / ((1.0f / masses[v1]) + (1.0f / masses[v2]));
-
-			mul_v3_fl(vec, -(1.0f / masses[v1]) * l);
-			add_v3_v3(cos[v1], vec);
-
-			sub_v3_v3v3(vec, cos[v2], cos[v1]);
-			normalize_v3(vec);
-
-			mul_v3_fl(vec, -(1.0f / masses[v2]) * l);
-			add_v3_v3(cos[v2], vec);
-		}
-	}
-
-	cv = cloth->verts;
-	for (i = 0; i < cloth->mvert_num; i++, cv++) {
-		float vec[3];
-
-		/*compute forces*/
-		sub_v3_v3v3(vec, cos[i], cv->tx);
-		mul_v3_fl(vec, cv->mass * dt * 20.0f);
-		add_v3_v3(cv->tv, vec);
-		//copy_v3_v3(cv->tx, cos[i]);
-	}
-
-	MEM_freeN(cos);
-	MEM_freeN(masses);
-
-	return 1;
+  Cloth *cloth = clmd->clothObject;
+  float(*cos)[3] = (float(*)[3])MEM_callocN(sizeof(float[3]) * cloth->mvert_num,
+                                            "cos cloth_calc_helper_forces");
+  float *masses = (float *)MEM_callocN(sizeof(float) * cloth->mvert_num,
+                                       "cos cloth_calc_helper_forces");
+  LinkNode *node;
+  ClothSpring *spring;
+  ClothVertex *cv;
+  int i, steps;
+
+  cv = cloth->verts;
+  for (i = 0; i < cloth->mvert_num; i++, cv++) {
+    copy_v3_v3(cos[i], cv->tx);
+
+    if (cv->goal == 1.0f || len_squared_v3v3(initial_cos[i], cv->tx) != 0.0f) {
+      masses[i] = 1e+10;
+    }
+    else {
+      masses[i] = cv->mass;
+    }
+  }
+
+  steps = 55;
+  for (i = 0; i < steps; i++) {
+    for (node = cloth->springs; node; node = node->next) {
+      /* ClothVertex *cv1, *cv2; */ /* UNUSED */
+      int v1, v2;
+      float len, c, l, vec[3];
+
+      spring = (ClothSpring *)node->link;
+      if (spring->type != CLOTH_SPRING_TYPE_STRUCTURAL && spring->type != CLOTH_SPRING_TYPE_SHEAR)
+        continue;
+
+      v1 = spring->ij;
+      v2 = spring->kl;
+      /* cv1 = cloth->verts + v1; */ /* UNUSED */
+      /* cv2 = cloth->verts + v2; */ /* UNUSED */
+      len = len_v3v3(cos[v1], cos[v2]);
+
+      sub_v3_v3v3(vec, cos[v1], cos[v2]);
+      normalize_v3(vec);
+
+      c = (len - spring->restlen);
+      if (c == 0.0f)
+        continue;
+
+      l = c / ((1.0f / masses[v1]) + (1.0f / masses[v2]));
+
+      mul_v3_fl(vec, -(1.0f / masses[v1]) * l);
+      add_v3_v3(cos[v1], vec);
+
+      sub_v3_v3v3(vec, cos[v2], cos[v1]);
+      normalize_v3(vec);
+
+      mul_v3_fl(vec, -(1.0f / masses[v2]) * l);
+      add_v3_v3(cos[v2], vec);
+    }
+  }
+
+  cv = cloth->verts;
+  for (i = 0; i < cloth->mvert_num; i++, cv++) {
+    float vec[3];
+
+    /*compute forces*/
+    sub_v3_v3v3(vec, cos[i], cv->tx);
+    mul_v3_fl(vec, cv->mass * dt * 20.0f);
+    add_v3_v3(cv->tv, vec);
+    //copy_v3_v3(cv->tx, cos[i]);
+  }
+
+  MEM_freeN(cos);
+  MEM_freeN(masses);
+
+  return 1;
 }
 
 BLI_INLINE void cloth_calc_spring_force(ClothModifierData *clmd, ClothSpring *s)
 {
-	Cloth *cloth = clmd->clothObject;
-	ClothSimSettings *parms = clmd->sim_parms;
-	Implicit_Data *data = cloth->implicit;
-	bool using_angular = parms->bending_model == CLOTH_BENDING_ANGULAR;
-	bool resist_compress = (parms->flags & CLOTH_SIMSETTINGS_FLAG_RESIST_SPRING_COMPRESS) && !using_angular;
+  Cloth *cloth = clmd->clothObject;
+  ClothSimSettings *parms = clmd->sim_parms;
+  Implicit_Data *data = cloth->implicit;
+  bool using_angular = parms->bending_model == CLOTH_BENDING_ANGULAR;
+  bool resist_compress = (parms->flags & CLOTH_SIMSETTINGS_FLAG_RESIST_SPRING_COMPRESS) &&
+                         !using_angular;
 
-	s->flags &= ~CLOTH_SPRING_FLAG_NEEDED;
+  s->flags &= ~CLOTH_SPRING_FLAG_NEEDED;
 
-	/* Calculate force of bending springs. */
-	if ((s->type & CLOTH_SPRING_TYPE_BENDING) && using_angular) {
+  /* Calculate force of bending springs. */
+  if ((s->type & CLOTH_SPRING_TYPE_BENDING) && using_angular) {
 #ifdef CLOTH_FORCE_SPRING_BEND
-		float k, scaling;
+    float k, scaling;
 
-		s->flags |= CLOTH_SPRING_FLAG_NEEDED;
+    s->flags |= CLOTH_SPRING_FLAG_NEEDED;
 
-		scaling = parms->bending + s->ang_stiffness * fabsf(parms->max_bend - parms->bending);
-		k = scaling * s->restlen * 0.1f; /* Multiplying by 0.1, just to scale the forces to more reasonable values. */
+    scaling = parms->bending + s->ang_stiffness * fabsf(parms->max_bend - parms->bending);
+    k = scaling * s->restlen *
+        0.1f; /* Multiplying by 0.1, just to scale the forces to more reasonable values. */
 
-		BPH_mass_spring_force_spring_angular(data, s->ij, s->kl, s->pa, s->pb, s->la, s->lb,
-		                                     s->restang, k, parms->bending_damping);
+    BPH_mass_spring_force_spring_angular(
+        data, s->ij, s->kl, s->pa, s->pb, s->la, s->lb, s->restang, k, parms->bending_damping);
 #endif
-	}
+  }
 
-	/* Calculate force of structural + shear springs. */
-	if (s->type & (CLOTH_SPRING_TYPE_STRUCTURAL | CLOTH_SPRING_TYPE_SEWING)) {
+  /* Calculate force of structural + shear springs. */
+  if (s->type & (CLOTH_SPRING_TYPE_STRUCTURAL | CLOTH_SPRING_TYPE_SEWING)) {
 #ifdef CLOTH_FORCE_SPRING_STRUCTURAL
-		float k_tension, scaling_tension;
-
-		s->flags |= CLOTH_SPRING_FLAG_NEEDED;
-
-		scaling_tension = parms->tension + s->lin_stiffness * fabsf(parms->max_tension - parms->tension);
-		k_tension = scaling_tension / (parms->avg_spring_len + FLT_EPSILON);
-
-		if (s->type & CLOTH_SPRING_TYPE_SEWING) {
-			// TODO: verify, half verified (couldn't see error)
-			// sewing springs usually have a large distance at first so clamp the force so we don't get tunnelling through colission objects
-			BPH_mass_spring_force_spring_linear(data, s->ij, s->kl, s->restlen,
-			                                    k_tension, parms->tension_damp,
-			                                    0.0f, 0.0f, false, false, parms->max_sewing);
-		}
-		else {
-			float k_compression, scaling_compression;
-			scaling_compression = parms->compression + s->lin_stiffness * fabsf(parms->max_compression - parms->compression);
-			k_compression = scaling_compression / (parms->avg_spring_len + FLT_EPSILON);
-
-			BPH_mass_spring_force_spring_linear(data, s->ij, s->kl, s->restlen,
-			                                    k_tension, parms->tension_damp,
-			                                    k_compression, parms->compression_damp,
-			                                    resist_compress, using_angular, 0.0f);
-		}
+    float k_tension, scaling_tension;
+
+    s->flags |= CLOTH_SPRING_FLAG_NEEDED;
+
+    scaling_tension = parms->tension +
+                      s->lin_stiffness * fabsf(parms->max_tension - parms->tension);
+    k_tension = scaling_tension / (parms->avg_spring_len + FLT_EPSILON);
+
+    if (s->type & CLOTH_SPRING_TYPE_SEWING) {
+      // TODO: verify, half verified (couldn't see error)
+      // sewing springs usually have a large distance at first so clamp the force so we don't get tunnelling through colission objects
+      BPH_mass_spring_force_spring_linear(data,
+                                          s->ij,
+                                          s->kl,
+                                          s->restlen,
+                                          k_tension,
+                                          parms->tension_damp,
+                                          0.0f,
+                                          0.0f,
+                                          false,
+                                          false,
+                                          parms->max_sewing);
+    }
+    else {
+      float k_compression, scaling_compression;
+      scaling_compression = parms->compression +
+                            s->lin_stiffness * fabsf(parms->max_compression - parms->compression);
+      k_compression = scaling_compression / (parms->avg_spring_len + FLT_EPSILON);
+
+      BPH_mass_spring_force_spring_linear(data,
+                                          s->ij,
+                                          s->kl,
+                                          s->restlen,
+                                          k_tension,
+                                          parms->tension_damp,
+                                          k_compression,
+                                          parms->compression_damp,
+                                          resist_compress,
+                                          using_angular,
+                                          0.0f);
+    }
 #endif
-	}
-	else if (s->type & CLOTH_SPRING_TYPE_SHEAR) {
+  }
+  else if (s->type & CLOTH_SPRING_TYPE_SHEAR) {
 #ifdef CLOTH_FORCE_SPRING_SHEAR
-		float k, scaling;
-
-		s->flags |= CLOTH_SPRING_FLAG_NEEDED;
-
-		scaling = parms->shear + s->lin_stiffness * fabsf(parms->max_shear - parms->shear);
-		k = scaling / (parms->avg_spring_len + FLT_EPSILON);
-
-		BPH_mass_spring_force_spring_linear(data, s->ij, s->kl, s->restlen, k, parms->shear_damp,
-		                                    0.0f, 0.0f, resist_compress, false, 0.0f);
+    float k, scaling;
+
+    s->flags |= CLOTH_SPRING_FLAG_NEEDED;
+
+    scaling = parms->shear + s->lin_stiffness * fabsf(parms->max_shear - parms->shear);
+    k = scaling / (parms->avg_spring_len + FLT_EPSILON);
+
+    BPH_mass_spring_force_spring_linear(data,
+                                        s->ij,
+                                        s->kl,
+                                        s->restlen,
+                                        k,
+                                        parms->shear_damp,
+                                        0.0f,
+                                        0.0f,
+                                        resist_compress,
+                                        false,
+                                        0.0f);
 #endif
-	}
-	else if (s->type & CLOTH_SPRING_TYPE_BENDING) {  /* calculate force of bending springs */
+  }
+  else if (s->type & CLOTH_SPRING_TYPE_BENDING) { /* calculate force of bending springs */
 #ifdef CLOTH_FORCE_SPRING_BEND
-		float kb, cb, scaling;
+    float kb, cb, scaling;
 
-		s->flags |= CLOTH_SPRING_FLAG_NEEDED;
+    s->flags |= CLOTH_SPRING_FLAG_NEEDED;
 
-		scaling = parms->bending + s->lin_stiffness * fabsf(parms->max_bend - parms->bending);
-		kb = scaling / (20.0f * (parms->avg_spring_len + FLT_EPSILON));
+    scaling = parms->bending + s->lin_stiffness * fabsf(parms->max_bend - parms->bending);
+    kb = scaling / (20.0f * (parms->avg_spring_len + FLT_EPSILON));
 
-		// Fix for [#45084] for cloth stiffness must have cb proportional to kb
-		cb = kb * parms->bending_damping;
+    // Fix for [#45084] for cloth stiffness must have cb proportional to kb
+    cb = kb * parms->bending_damping;
 
-		BPH_mass_spring_force_spring_bending(data, s->ij, s->kl, s->restlen, kb, cb);
+    BPH_mass_spring_force_spring_bending(data, s->ij, s->kl, s->restlen, kb, cb);
 #endif
-	}
-	else if (s->type & CLOTH_SPRING_TYPE_BENDING_HAIR) {
+  }
+  else if (s->type & CLOTH_SPRING_TYPE_BENDING_HAIR) {
 #ifdef CLOTH_FORCE_SPRING_BEND
-		float kb, cb, scaling;
+    float kb, cb, scaling;
 
-		s->flags |= CLOTH_SPRING_FLAG_NEEDED;
+    s->flags |= CLOTH_SPRING_FLAG_NEEDED;
 
-		/* XXX WARNING: angular bending springs for hair apply stiffness factor as an overall factor, unlike cloth springs!
-		 * this is crap, but needed due to cloth/hair mixing ...
-		 * max_bend factor is not even used for hair, so ...
-		 */
-		scaling = s->lin_stiffness * parms->bending;
-		kb = scaling / (20.0f * (parms->avg_spring_len + FLT_EPSILON));
+    /* XXX WARNING: angular bending springs for hair apply stiffness factor as an overall factor, unlike cloth springs!
+     * this is crap, but needed due to cloth/hair mixing ...
+     * max_bend factor is not even used for hair, so ...
+     */
+    scaling = s->lin_stiffness * parms->bending;
+    kb = scaling / (20.0f * (parms->avg_spring_len + FLT_EPSILON));
 
-		// Fix for [#45084] for cloth stiffness must have cb proportional to kb
-		cb = kb * parms->bending_damping;
+    // Fix for [#45084] for cloth stiffness must have cb proportional to kb
+    cb = kb * parms->bending_damping;
 
-		/* XXX assuming same restlen for ij and jk segments here, this can be done correctly for hair later */
-		BPH_mass_spring_force_spring_bending_hair(data, s->ij, s->kl, s->mn, s->target, kb, cb);
+    /* XXX assuming same restlen for ij and jk segments here, this can be done correctly for hair later */
+    BPH_mass_spring_force_spring_bending_hair(data, s->ij, s->kl, s->mn, s->target, kb, cb);
 
-#if 0
-		{
-			float x_kl[3], x_mn[3], v[3], d[3];
+#  if 0
+    {
+      float x_kl[3], x_mn[3], v[3], d[3];
 
-			BPH_mass_spring_get_motion_state(data, s->kl, x_kl, v);
-			BPH_mass_spring_get_motion_state(data, s->mn, x_mn, v);
+      BPH_mass_spring_get_motion_state(data, s->kl, x_kl, v);
+      BPH_mass_spring_get_motion_state(data, s->mn, x_mn, v);
 
-			BKE_sim_debug_data_add_dot(clmd->debug_data, x_kl, 0.9, 0.9, 0.9, "target", 7980, s->kl);
-			BKE_sim_debug_data_add_line(clmd->debug_data, x_kl, x_mn, 0.8, 0.8, 0.8, "target", 7981, s->kl);
+      BKE_sim_debug_data_add_dot(clmd->debug_data, x_kl, 0.9, 0.9, 0.9, "target", 7980, s->kl);
+      BKE_sim_debug_data_add_line(clmd->debug_data, x_kl, x_mn, 0.8, 0.8, 0.8, "target", 7981, s->kl);
 
-			copy_v3_v3(d, s->target);
-			BKE_sim_debug_data_add_vector(clmd->debug_data, x_kl, d, 0.8, 0.8, 0.2, "target", 7982, s->kl);
+      copy_v3_v3(d, s->target);
+      BKE_sim_debug_data_add_vector(clmd->debug_data, x_kl, d, 0.8, 0.8, 0.2, "target", 7982, s->kl);
 
-//			copy_v3_v3(d, s->target_ij);
-//			BKE_sim_debug_data_add_vector(clmd->debug_data, x, d, 1, 0.4, 0.4, "target", 7983, s->kl);
-		}
-#endif
+//          copy_v3_v3(d, s->target_ij);
+//          BKE_sim_debug_data_add_vector(clmd->debug_data, x, d, 1, 0.4, 0.4, "target", 7983, s->kl);
+    }
+#  endif
 #endif
-	}
+  }
 }
 
 static void hair_get_boundbox(ClothModifierData *clmd, float gmin[3], float gmax[3])
 {
-	Cloth *cloth = clmd->clothObject;
-	Implicit_Data *data = cloth->implicit;
-	unsigned int mvert_num = cloth->mvert_num;
-	int i;
-
-	INIT_MINMAX(gmin, gmax);
-	for (i = 0; i < mvert_num; i++) {
-		float x[3];
-		BPH_mass_spring_get_motion_state(data, i, x, NULL);
-		DO_MINMAX(x, gmin, gmax);
-	}
+  Cloth *cloth = clmd->clothObject;
+  Implicit_Data *data = cloth->implicit;
+  unsigned int mvert_num = cloth->mvert_num;
+  int i;
+
+  INIT_MINMAX(gmin, gmax);
+  for (i = 0; i < mvert_num; i++) {
+    float x[3];
+    BPH_mass_spring_get_motion_state(data, i, x, NULL);
+    DO_MINMAX(x, gmin, gmax);
+  }
 }
 
-static void cloth_calc_force(Scene *scene, ClothModifierData *clmd, float UNUSED(frame), ListBase *effectors, float time)
+static void cloth_calc_force(
+    Scene *scene, ClothModifierData *clmd, float UNUSED(frame), ListBase *effectors, float time)
 {
-	/* Collect forces and derivatives:  F, dFdX, dFdV */
-	Cloth *cloth = clmd->clothObject;
-	Implicit_Data *data = cloth->implicit;
-	unsigned int i  = 0;
-	float drag    = clmd->sim_parms->Cvi * 0.01f;       /* viscosity of air scaled in percent */
-	float gravity[3] = {0.0f, 0.0f, 0.0f};
-	const MVertTri *tri     = cloth->tri;
-	unsigned int mvert_num = cloth->mvert_num;
-	ClothVertex *vert;
+  /* Collect forces and derivatives:  F, dFdX, dFdV */
+  Cloth *cloth = clmd->clothObject;
+  Implicit_Data *data = cloth->implicit;
+  unsigned int i = 0;
+  float drag = clmd->sim_parms->Cvi * 0.01f; /* viscosity of air scaled in percent */
+  float gravity[3] = {0.0f, 0.0f, 0.0f};
+  const MVertTri *tri = cloth->tri;
+  unsigned int mvert_num = cloth->mvert_num;
+  ClothVertex *vert;
 
 #ifdef CLOTH_FORCE_GRAVITY
-	/* global acceleration (gravitation) */
-	if (scene->physics_settings.flag & PHYS_GLOBAL_GRAVITY) {
-		/* scale gravity force */
-		mul_v3_v3fl(gravity, scene->physics_settings.gravity, 0.001f * clmd->sim_parms->effector_weights->global_gravity);
-	}
-
-	vert = cloth->verts;
-	for (i = 0; i < cloth->mvert_num; i++, vert++) {
-		BPH_mass_spring_force_gravity(data, i, vert->mass, gravity);
-
-		/* Vertex goal springs */
-		if ((!(vert->flags & CLOTH_VERT_FLAG_PINNED)) && (vert->goal > FLT_EPSILON)) {
-			float goal_x[3], goal_v[3];
-			float k;
-
-			/* divide by time_scale to prevent goal vertices' delta locations from being multiplied */
-			interp_v3_v3v3(goal_x, vert->xold, vert->xconst, time / clmd->sim_parms->time_scale);
-			sub_v3_v3v3(goal_v, vert->xconst, vert->xold); /* distance covered over dt==1 */
-
-			k = vert->goal * clmd->sim_parms->goalspring / (clmd->sim_parms->avg_spring_len + FLT_EPSILON);
-
-			BPH_mass_spring_force_spring_goal(data, i, goal_x, goal_v, k, clmd->sim_parms->goalfrict * 0.01f);
-		}
-	}
+  /* global acceleration (gravitation) */
+  if (scene->physics_settings.flag & PHYS_GLOBAL_GRAVITY) {
+    /* scale gravity force */
+    mul_v3_v3fl(gravity,
+                scene->physics_settings.gravity,
+                0.001f * clmd->sim_parms->effector_weights->global_gravity);
+  }
+
+  vert = cloth->verts;
+  for (i = 0; i < cloth->mvert_num; i++, vert++) {
+    BPH_mass_spring_force_gravity(data, i, vert->mass, gravity);
+
+    /* Vertex goal springs */
+    if ((!(vert->flags & CLOTH_VERT_FLAG_PINNED)) && (vert->goal > FLT_EPSILON)) {
+      float goal_x[3], goal_v[3];
+      float k;
+
+      /* divide by time_scale to prevent goal vertices' delta locations from being multiplied */
+      interp_v3_v3v3(goal_x, vert->xold, vert->xconst, time / clmd->sim_parms->time_scale);
+      sub_v3_v3v3(goal_v, vert->xconst, vert->xold); /* distance covered over dt==1 */
+
+      k = vert->goal * clmd->sim_parms->goalspring /
+          (clmd->sim_parms->avg_spring_len + FLT_EPSILON);
+
+      BPH_mass_spring_force_spring_goal(
+          data, i, goal_x, goal_v, k, clmd->sim_parms->goalfrict * 0.01f);
+    }
+  }
 #endif
 
-	/* cloth_calc_volume_force(clmd); */
+  /* cloth_calc_volume_force(clmd); */
 
 #ifdef CLOTH_FORCE_DRAG
-	BPH_mass_spring_force_drag(data, drag);
+  BPH_mass_spring_force_drag(data, drag);
 #endif
 
-	/* handle external forces like wind */
-	if (effectors) {
-		/* cache per-vertex forces to avoid redundant calculation */
-		float(*winvec)[3] = (float(*)[3])MEM_callocN(sizeof(float[3]) * mvert_num, "effector forces");
-		for (i = 0; i < cloth->mvert_num; i++) {
-			float x[3], v[3];
-			EffectedPoint epoint;
-
-			BPH_mass_spring_get_motion_state(data, i, x, v);
-			pd_point_from_loc(scene, x, v, i, &epoint);
-			BKE_effectors_apply(effectors, NULL, clmd->sim_parms->effector_weights, &epoint, winvec[i], NULL);
-		}
-
-		for (i = 0; i < cloth->tri_num; i++) {
-			const MVertTri *vt = &tri[i];
-			BPH_mass_spring_force_face_wind(data, vt->tri[0], vt->tri[1], vt->tri[2], winvec);
-		}
-
-		/* Hair has only edges */
-		if (cloth->tri_num == 0) {
+  /* handle external forces like wind */
+  if (effectors) {
+    /* cache per-vertex forces to avoid redundant calculation */
+    float(*winvec)[3] = (float(*)[3])MEM_callocN(sizeof(float[3]) * mvert_num, "effector forces");
+    for (i = 0; i < cloth->mvert_num; i++) {
+      float x[3], v[3];
+      EffectedPoint epoint;
+
+      BPH_mass_spring_get_motion_state(data, i, x, v);
+      pd_point_from_loc(scene, x, v, i, &epoint);
+      BKE_effectors_apply(
+          effectors, NULL, clmd->sim_parms->effector_weights, &epoint, winvec[i], NULL);
+    }
+
+    for (i = 0; i < cloth->tri_num; i++) {
+      const MVertTri *vt = &tri[i];
+      BPH_mass_spring_force_face_wind(data, vt->tri[0], vt->tri[1], vt->tri[2], winvec);
+    }
+
+    /* Hair has only edges */
+    if (cloth->tri_num == 0) {
 #if 0
-			ClothHairData *hairdata = clmd->hairdata;
-			ClothHairData *hair_ij, *hair_kl;
-
-			for (LinkNode *link = cloth->springs; link; link = link->next) {
-				ClothSpring *spring = (ClothSpring *)link->link;
-				if (spring->type == CLOTH_SPRING_TYPE_STRUCTURAL) {
-					if (hairdata) {
-						hair_ij = &hairdata[spring->ij];
-						hair_kl = &hairdata[spring->kl];
-						BPH_mass_spring_force_edge_wind(data, spring->ij, spring->kl, hair_ij->radius, hair_kl->radius, winvec);
-					}
-					else
-						BPH_mass_spring_force_edge_wind(data, spring->ij, spring->kl, 1.0f, 1.0f, winvec);
-				}
-			}
+      ClothHairData *hairdata = clmd->hairdata;
+      ClothHairData *hair_ij, *hair_kl;
+
+      for (LinkNode *link = cloth->springs; link; link = link->next) {
+        ClothSpring *spring = (ClothSpring *)link->link;
+        if (spring->type == CLOTH_SPRING_TYPE_STRUCTURAL) {
+          if (hairdata) {
+            hair_ij = &hairdata[spring->ij];
+            hair_kl = &hairdata[spring->kl];
+            BPH_mass_spring_force_edge_wind(data, spring->ij, spring->kl, hair_ij->radius, hair_kl->radius, winvec);
+          }
+          else
+            BPH_mass_spring_force_edge_wind(data, spring->ij, spring->kl, 1.0f, 1.0f, winvec);
+        }
+      }
 #else
-			ClothHairData *hairdata = clmd->hairdata;
-
-			vert = cloth->verts;
-			for (i = 0; i < cloth->mvert_num; i++, vert++) {
-				if (hairdata) {
-					ClothHairData *hair = &hairdata[i];
-					BPH_mass_spring_force_vertex_wind(data, i, hair->radius, winvec);
-				}
-				else
-					BPH_mass_spring_force_vertex_wind(data, i, 1.0f, winvec);
-			}
+      ClothHairData *hairdata = clmd->hairdata;
+
+      vert = cloth->verts;
+      for (i = 0; i < cloth->mvert_num; i++, vert++) {
+        if (hairdata) {
+          ClothHairData *hair = &hairdata[i];
+          BPH_mass_spring_force_vertex_wind(data, i, hair->radius, winvec);
+        }
+        else
+          BPH_mass_spring_force_vertex_wind(data, i, 1.0f, winvec);
+      }
 #endif
-		}
-
-		MEM_freeN(winvec);
-	}
-
-	// calculate spring forces
-	for (LinkNode *link = cloth->springs; link; link = link->next) {
-		ClothSpring *spring = (ClothSpring *)link->link;
-		// only handle active springs
-		if (!(spring->flags & CLOTH_SPRING_FLAG_DEACTIVATE)) {
-			cloth_calc_spring_force(clmd, spring);
-		}
-	}
+    }
+
+    MEM_freeN(winvec);
+  }
+
+  // calculate spring forces
+  for (LinkNode *link = cloth->springs; link; link = link->next) {
+    ClothSpring *spring = (ClothSpring *)link->link;
+    // only handle active springs
+    if (!(spring->flags & CLOTH_SPRING_FLAG_DEACTIVATE)) {
+      cloth_calc_spring_force(clmd, spring);
+    }
+  }
 }
 
 /* returns vertexes' motion state */
-BLI_INLINE void cloth_get_grid_location(Implicit_Data *data, float cell_scale, const float cell_offset[3],
-                                        int index, float x[3], float v[3])
+BLI_INLINE void cloth_get_grid_location(Implicit_Data *data,
+                                        float cell_scale,
+                                        const float cell_offset[3],
+                                        int index,
+                                        float x[3],
+                                        float v[3])
 {
-	BPH_mass_spring_get_position(data, index, x);
-	BPH_mass_spring_get_new_velocity(data, index, v);
+  BPH_mass_spring_get_position(data, index, x);
+  BPH_mass_spring_get_new_velocity(data, index, v);
 
-	mul_v3_fl(x, cell_scale);
-	add_v3_v3(x, cell_offset);
+  mul_v3_fl(x, cell_scale);
+  add_v3_v3(x, cell_offset);
 }
 
 /* returns next spring forming a continuous hair sequence */
 BLI_INLINE LinkNode *hair_spring_next(LinkNode *spring_link)
 {
-	ClothSpring *spring = (ClothSpring *)spring_link->link;
-	LinkNode *next = spring_link->next;
-	if (next) {
-		ClothSpring *next_spring = (ClothSpring *)next->link;
-		if (next_spring->type == CLOTH_SPRING_TYPE_STRUCTURAL && next_spring->kl == spring->ij)
-			return next;
-	}
-	return NULL;
+  ClothSpring *spring = (ClothSpring *)spring_link->link;
+  LinkNode *next = spring_link->next;
+  if (next) {
+    ClothSpring *next_spring = (ClothSpring *)next->link;
+    if (next_spring->type == CLOTH_SPRING_TYPE_STRUCTURAL && next_spring->kl == spring->ij)
+      return next;
+  }
+  return NULL;
 }
 
 /* XXX this is nasty: cloth meshes do not explicitly store
@@ -605,459 +658,481 @@ BLI_INLINE LinkNode *hair_spring_next(LinkNode *spring_link)
  *   (3,4), (2,3), (1,2)
  * This is currently the only way to figure out hair geometry inside this code ...
  */
-static LinkNode *cloth_continuum_add_hair_segments(HairGrid *grid, const float cell_scale, const float cell_offset[3], Cloth *cloth, LinkNode *spring_link)
+static LinkNode *cloth_continuum_add_hair_segments(HairGrid *grid,
+                                                   const float cell_scale,
+                                                   const float cell_offset[3],
+                                                   Cloth *cloth,
+                                                   LinkNode *spring_link)
 {
-	Implicit_Data *data = cloth->implicit;
-	LinkNode *next_spring_link = NULL;     /* return value */
-	ClothSpring *spring1, *spring2, *spring3;
-	// ClothVertex *verts = cloth->verts;
-	// ClothVertex *vert3, *vert4;
-	float x1[3], v1[3], x2[3], v2[3], x3[3], v3[3], x4[3], v4[3];
-	float dir1[3], dir2[3], dir3[3];
-
-	spring1 = NULL;
-	spring2 = NULL;
-	spring3 = (ClothSpring *)spring_link->link;
-
-	zero_v3(x1); zero_v3(v1);
-	zero_v3(dir1);
-	zero_v3(x2); zero_v3(v2);
-	zero_v3(dir2);
-
-	// vert3 = &verts[spring3->kl];
-	cloth_get_grid_location(data, cell_scale, cell_offset, spring3->kl, x3, v3);
-	// vert4 = &verts[spring3->ij];
-	cloth_get_grid_location(data, cell_scale, cell_offset, spring3->ij, x4, v4);
-	sub_v3_v3v3(dir3, x4, x3);
-	normalize_v3(dir3);
-
-	while (spring_link) {
-		/* move on */
-		spring1 = spring2;
-		spring2 = spring3;
-
-		// vert3 = vert4;
-
-		copy_v3_v3(x1, x2); copy_v3_v3(v1, v2);
-		copy_v3_v3(x2, x3); copy_v3_v3(v2, v3);
-		copy_v3_v3(x3, x4); copy_v3_v3(v3, v4);
-
-		copy_v3_v3(dir1, dir2);
-		copy_v3_v3(dir2, dir3);
-
-		/* read next segment */
-		next_spring_link = spring_link->next;
-		spring_link = hair_spring_next(spring_link);
-
-		if (spring_link) {
-			spring3 = (ClothSpring *)spring_link->link;
-			// vert4 = &verts[spring3->ij];
-			cloth_get_grid_location(data, cell_scale, cell_offset, spring3->ij, x4, v4);
-			sub_v3_v3v3(dir3, x4, x3);
-			normalize_v3(dir3);
-		}
-		else {
-			spring3 = NULL;
-			// vert4 = NULL;
-			zero_v3(x4); zero_v3(v4);
-			zero_v3(dir3);
-		}
-
-		BPH_hair_volume_add_segment(grid, x1, v1, x2, v2, x3, v3, x4, v4,
-		                            spring1 ? dir1 : NULL,
-		                            dir2,
-		                            spring3 ? dir3 : NULL);
-	}
-
-	return next_spring_link;
+  Implicit_Data *data = cloth->implicit;
+  LinkNode *next_spring_link = NULL; /* return value */
+  ClothSpring *spring1, *spring2, *spring3;
+  // ClothVertex *verts = cloth->verts;
+  // ClothVertex *vert3, *vert4;
+  float x1[3], v1[3], x2[3], v2[3], x3[3], v3[3], x4[3], v4[3];
+  float dir1[3], dir2[3], dir3[3];
+
+  spring1 = NULL;
+  spring2 = NULL;
+  spring3 = (ClothSpring *)spring_link->link;
+
+  zero_v3(x1);
+  zero_v3(v1);
+  zero_v3(dir1);
+  zero_v3(x2);
+  zero_v3(v2);
+  zero_v3(dir2);
+
+  // vert3 = &verts[spring3->kl];
+  cloth_get_grid_location(data, cell_scale, cell_offset, spring3->kl, x3, v3);
+  // vert4 = &verts[spring3->ij];
+  cloth_get_grid_location(data, cell_scale, cell_offset, spring3->ij, x4, v4);
+  sub_v3_v3v3(dir3, x4, x3);
+  normalize_v3(dir3);
+
+  while (spring_link) {
+    /* move on */
+    spring1 = spring2;
+    spring2 = spring3;
+
+    // vert3 = vert4;
+
+    copy_v3_v3(x1, x2);
+    copy_v3_v3(v1, v2);
+    copy_v3_v3(x2, x3);
+    copy_v3_v3(v2, v3);
+    copy_v3_v3(x3, x4);
+    copy_v3_v3(v3, v4);
+
+    copy_v3_v3(dir1, dir2);
+    copy_v3_v3(dir2, dir3);
+
+    /* read next segment */
+    next_spring_link = spring_link->next;
+    spring_link = hair_spring_next(spring_link);
+
+    if (spring_link) {
+      spring3 = (ClothSpring *)spring_link->link;
+      // vert4 = &verts[spring3->ij];
+      cloth_get_grid_location(data, cell_scale, cell_offset, spring3->ij, x4, v4);
+      sub_v3_v3v3(dir3, x4, x3);
+      normalize_v3(dir3);
+    }
+    else {
+      spring3 = NULL;
+      // vert4 = NULL;
+      zero_v3(x4);
+      zero_v3(v4);
+      zero_v3(dir3);
+    }
+
+    BPH_hair_volume_add_segment(
+        grid, x1, v1, x2, v2, x3, v3, x4, v4, spring1 ? dir1 : NULL, dir2, spring3 ? dir3 : NULL);
+  }
+
+  return next_spring_link;
 }
 
 static void cloth_continuum_fill_grid(HairGrid *grid, Cloth *cloth)
 {
 #if 0
-	Implicit_Data *data = cloth->implicit;
-	int mvert_num = cloth->mvert_num;
-	ClothVertex *vert;
-	int i;
+  Implicit_Data *data = cloth->implicit;
+  int mvert_num = cloth->mvert_num;
+  ClothVertex *vert;
+  int i;
 
-	for (i = 0, vert = cloth->verts; i < mvert_num; i++, vert++) {
-		float x[3], v[3];
+  for (i = 0, vert = cloth->verts; i < mvert_num; i++, vert++) {
+    float x[3], v[3];
 
-		cloth_get_vertex_motion_state(data, vert, x, v);
-		BPH_hair_volume_add_vertex(grid, x, v);
-	}
+    cloth_get_vertex_motion_state(data, vert, x, v);
+    BPH_hair_volume_add_vertex(grid, x, v);
+  }
 #else
-	LinkNode *link;
-	float cellsize, gmin[3], cell_scale, cell_offset[3];
-
-	/* scale and offset for transforming vertex locations into grid space
-	 * (cell size is 0..1, gmin becomes origin)
-	 */
-	BPH_hair_volume_grid_geometry(grid, &cellsize, NULL, gmin, NULL);
-	cell_scale = cellsize > 0.0f ? 1.0f / cellsize : 0.0f;
-	mul_v3_v3fl(cell_offset, gmin, cell_scale);
-	negate_v3(cell_offset);
-
-	link = cloth->springs;
-	while (link) {
-		ClothSpring *spring = (ClothSpring *)link->link;
-		if (spring->type == CLOTH_SPRING_TYPE_STRUCTURAL)
-			link = cloth_continuum_add_hair_segments(grid, cell_scale, cell_offset, cloth, link);
-		else
-			link = link->next;
-	}
+  LinkNode *link;
+  float cellsize, gmin[3], cell_scale, cell_offset[3];
+
+  /* scale and offset for transforming vertex locations into grid space
+   * (cell size is 0..1, gmin becomes origin)
+   */
+  BPH_hair_volume_grid_geometry(grid, &cellsize, NULL, gmin, NULL);
+  cell_scale = cellsize > 0.0f ? 1.0f / cellsize : 0.0f;
+  mul_v3_v3fl(cell_offset, gmin, cell_scale);
+  negate_v3(cell_offset);
+
+  link = cloth->springs;
+  while (link) {
+    ClothSpring *spring = (ClothSpring *)link->link;
+    if (spring->type == CLOTH_SPRING_TYPE_STRUCTURAL)
+      link = cloth_continuum_add_hair_segments(grid, cell_scale, cell_offset, cloth, link);
+    else
+      link = link->next;
+  }
 #endif
-	BPH_hair_volume_normalize_vertex_grid(grid);
+  BPH_hair_volume_normalize_vertex_grid(grid);
 }
 
 static void cloth_continuum_step(ClothModifierData *clmd, float dt)
 {
-	ClothSimSettings *parms = clmd->sim_parms;
-	Cloth *cloth = clmd->clothObject;
-	Implicit_Data *data = cloth->implicit;
-	int mvert_num = cloth->mvert_num;
-	ClothVertex *vert;
-
-	const float fluid_factor = 0.95f;     /* blend between PIC and FLIP methods */
-	float smoothfac = parms->velocity_smooth;
-	/* XXX FIXME arbitrary factor!!! this should be based on some intuitive value instead,
-	 * like number of hairs per cell and time decay instead of "strength"
-	 */
-	float density_target = parms->density_target;
-	float density_strength = parms->density_strength;
-	float gmin[3], gmax[3];
-	int i;
-
-	/* clear grid info */
-	zero_v3_int(clmd->hair_grid_res);
-	zero_v3(clmd->hair_grid_min);
-	zero_v3(clmd->hair_grid_max);
-	clmd->hair_grid_cellsize = 0.0f;
-
-	hair_get_boundbox(clmd, gmin, gmax);
-
-	/* gather velocities & density */
-	if (smoothfac > 0.0f || density_strength > 0.0f) {
-		HairGrid *grid = BPH_hair_volume_create_vertex_grid(clmd->sim_parms->voxel_cell_size, gmin, gmax);
-
-		cloth_continuum_fill_grid(grid, cloth);
-
-		/* main hair continuum solver */
-		BPH_hair_volume_solve_divergence(grid, dt, density_target, density_strength);
-
-		for (i = 0, vert = cloth->verts; i < mvert_num; i++, vert++) {
-			float x[3], v[3], nv[3];
-
-			/* calculate volumetric velocity influence */
-			BPH_mass_spring_get_position(data, i, x);
-			BPH_mass_spring_get_new_velocity(data, i, v);
-
-			BPH_hair_volume_grid_velocity(grid, x, v, fluid_factor, nv);
-
-			interp_v3_v3v3(nv, v, nv, smoothfac);
-
-			/* apply on hair data */
-			BPH_mass_spring_set_new_velocity(data, i, nv);
-		}
-
-		/* store basic grid info in the modifier data */
-		BPH_hair_volume_grid_geometry(grid, &clmd->hair_grid_cellsize, clmd->hair_grid_res, clmd->hair_grid_min, clmd->hair_grid_max);
+  ClothSimSettings *parms = clmd->sim_parms;
+  Cloth *cloth = clmd->clothObject;
+  Implicit_Data *data = cloth->implicit;
+  int mvert_num = cloth->mvert_num;
+  ClothVertex *vert;
+
+  const float fluid_factor = 0.95f; /* blend between PIC and FLIP methods */
+  float smoothfac = parms->velocity_smooth;
+  /* XXX FIXME arbitrary factor!!! this should be based on some intuitive value instead,
+   * like number of hairs per cell and time decay instead of "strength"
+   */
+  float density_target = parms->density_target;
+  float density_strength = parms->density_strength;
+  float gmin[3], gmax[3];
+  int i;
+
+  /* clear grid info */
+  zero_v3_int(clmd->hair_grid_res);
+  zero_v3(clmd->hair_grid_min);
+  zero_v3(clmd->hair_grid_max);
+  clmd->hair_grid_cellsize = 0.0f;
+
+  hair_get_boundbox(clmd, gmin, gmax);
+
+  /* gather velocities & density */
+  if (smoothfac > 0.0f || density_strength > 0.0f) {
+    HairGrid *grid = BPH_hair_volume_create_vertex_grid(
+        clmd->sim_parms->voxel_cell_size, gmin, gmax);
+
+    cloth_continuum_fill_grid(grid, cloth);
+
+    /* main hair continuum solver */
+    BPH_hair_volume_solve_divergence(grid, dt, density_target, density_strength);
+
+    for (i = 0, vert = cloth->verts; i < mvert_num; i++, vert++) {
+      float x[3], v[3], nv[3];
+
+      /* calculate volumetric velocity influence */
+      BPH_mass_spring_get_position(data, i, x);
+      BPH_mass_spring_get_new_velocity(data, i, v);
+
+      BPH_hair_volume_grid_velocity(grid, x, v, fluid_factor, nv);
+
+      interp_v3_v3v3(nv, v, nv, smoothfac);
+
+      /* apply on hair data */
+      BPH_mass_spring_set_new_velocity(data, i, nv);
+    }
+
+    /* store basic grid info in the modifier data */
+    BPH_hair_volume_grid_geometry(grid,
+                                  &clmd->hair_grid_cellsize,
+                                  clmd->hair_grid_res,
+                                  clmd->hair_grid_min,
+                                  clmd->hair_grid_max);
 
 #if 0 /* DEBUG hair velocity vector field */
-		{
-			const int size = 64;
-			int i, j;
-			float offset[3], a[3], b[3];
-			const int axis = 0;
-			const float shift = 0.0f;
-
-			copy_v3_v3(offset, clmd->hair_grid_min);
-			zero_v3(a);
-			zero_v3(b);
-
-			offset[axis] = shift * clmd->hair_grid_cellsize;
-			a[(axis + 1) % 3] = clmd->hair_grid_max[(axis + 1) % 3] - clmd->hair_grid_min[(axis + 1) % 3];
-			b[(axis + 2) % 3] = clmd->hair_grid_max[(axis + 2) % 3] - clmd->hair_grid_min[(axis + 2) % 3];
-
-			BKE_sim_debug_data_clear_category(clmd->debug_data, "grid velocity");
-			for (j = 0; j < size; ++j) {
-				for (i = 0; i < size; ++i) {
-					float x[3], v[3], gvel[3], gvel_smooth[3], gdensity;
-
-					madd_v3_v3v3fl(x, offset, a, (float)i / (float)(size - 1));
-					madd_v3_v3fl(x, b, (float)j / (float)(size - 1));
-					zero_v3(v);
-
-					BPH_hair_volume_grid_interpolate(grid, x, &gdensity, gvel, gvel_smooth, NULL, NULL);
-
-//					BKE_sim_debug_data_add_circle(clmd->debug_data, x, gdensity, 0.7, 0.3, 1, "grid density", i, j, 3111);
-					if (!is_zero_v3(gvel) || !is_zero_v3(gvel_smooth)) {
-						float dvel[3];
-						sub_v3_v3v3(dvel, gvel_smooth, gvel);
-//						BKE_sim_debug_data_add_vector(clmd->debug_data, x, gvel, 0.4, 0, 1, "grid velocity", i, j, 3112);
-//						BKE_sim_debug_data_add_vector(clmd->debug_data, x, gvel_smooth, 0.6, 1, 1, "grid velocity", i, j, 3113);
-						BKE_sim_debug_data_add_vector(clmd->debug_data, x, dvel, 0.4, 1, 0.7, "grid velocity", i, j, 3114);
-#if 0
-						if (gdensity > 0.0f) {
-							float col0[3] = {0.0, 0.0, 0.0};
-							float col1[3] = {0.0, 1.0, 0.0};
-							float col[3];
-
-							interp_v3_v3v3(col, col0, col1, CLAMPIS(gdensity * clmd->sim_parms->density_strength, 0.0, 1.0));
-//							BKE_sim_debug_data_add_circle(clmd->debug_data, x, gdensity * clmd->sim_parms->density_strength, 0, 1, 0.4, "grid velocity", i, j, 3115);
-//							BKE_sim_debug_data_add_dot(clmd->debug_data, x, col[0], col[1], col[2], "grid velocity", i, j, 3115);
-							BKE_sim_debug_data_add_circle(clmd->debug_data, x, 0.01f, col[0], col[1], col[2], "grid velocity", i, j, 3115);
-						}
-#endif
-					}
-				}
-			}
-		}
+    {
+      const int size = 64;
+      int i, j;
+      float offset[3], a[3], b[3];
+      const int axis = 0;
+      const float shift = 0.0f;
+
+      copy_v3_v3(offset, clmd->hair_grid_min);
+      zero_v3(a);
+      zero_v3(b);
+
+      offset[axis] = shift * clmd->hair_grid_cellsize;
+      a[(axis + 1) % 3] = clmd->hair_grid_max[(axis + 1) % 3] - clmd->hair_grid_min[(axis + 1) % 3];
+      b[(axis + 2) % 3] = clmd->hair_grid_max[(axis + 2) % 3] - clmd->hair_grid_min[(axis + 2) % 3];
+
+      BKE_sim_debug_data_clear_category(clmd->debug_data, "grid velocity");
+      for (j = 0; j < size; ++j) {
+        for (i = 0; i < size; ++i) {
+          float x[3], v[3], gvel[3], gvel_smooth[3], gdensity;
+
+          madd_v3_v3v3fl(x, offset, a, (float)i / (float)(size - 1));
+          madd_v3_v3fl(x, b, (float)j / (float)(size - 1));
+          zero_v3(v);
+
+          BPH_hair_volume_grid_interpolate(grid, x, &gdensity, gvel, gvel_smooth, NULL, NULL);
+
+//                  BKE_sim_debug_data_add_circle(clmd->debug_data, x, gdensity, 0.7, 0.3, 1, "grid density", i, j, 3111);
+          if (!is_zero_v3(gvel) || !is_zero_v3(gvel_smooth)) {
+            float dvel[3];
+            sub_v3_v3v3(dvel, gvel_smooth, gvel);
+//                      BKE_sim_debug_data_add_vector(clmd->debug_data, x, gvel, 0.4, 0, 1, "grid velocity", i, j, 3112);
+//                      BKE_sim_debug_data_add_vector(clmd->debug_data, x, gvel_smooth, 0.6, 1, 1, "grid velocity", i, j, 3113);
+            BKE_sim_debug_data_add_vector(clmd->debug_data, x, dvel, 0.4, 1, 0.7, "grid velocity", i, j, 3114);
+#  if 0
+            if (gdensity > 0.0f) {
+              float col0[3] = {0.0, 0.0, 0.0};
+              float col1[3] = {0.0, 1.0, 0.0};
+              float col[3];
+
+              interp_v3_v3v3(col, col0, col1, CLAMPIS(gdensity * clmd->sim_parms->density_strength, 0.0, 1.0));
+//                          BKE_sim_debug_data_add_circle(clmd->debug_data, x, gdensity * clmd->sim_parms->density_strength, 0, 1, 0.4, "grid velocity", i, j, 3115);
+//                          BKE_sim_debug_data_add_dot(clmd->debug_data, x, col[0], col[1], col[2], "grid velocity", i, j, 3115);
+              BKE_sim_debug_data_add_circle(clmd->debug_data, x, 0.01f, col[0], col[1], col[2], "grid velocity", i, j, 3115);
+            }
+#  endif
+          }
+        }
+      }
+    }
 #endif
 
-		BPH_hair_volume_free_vertex_grid(grid);
-	}
+    BPH_hair_volume_free_vertex_grid(grid);
+  }
 }
 
 #if 0
 static void cloth_calc_volume_force(ClothModifierData *clmd)
 {
-	ClothSimSettings *parms = clmd->sim_parms;
-	Cloth *cloth = clmd->clothObject;
-	Implicit_Data *data = cloth->implicit;
-	int mvert_num = cloth->mvert_num;
-	ClothVertex *vert;
-
-	/* 2.0f is an experimental value that seems to give good results */
-	float smoothfac = 2.0f * parms->velocity_smooth;
-	float collfac = 2.0f * parms->collider_friction;
-	float pressfac = parms->pressure;
-	float minpress = parms->pressure_threshold;
-	float gmin[3], gmax[3];
-	int i;
-
-	hair_get_boundbox(clmd, gmin, gmax);
-
-	/* gather velocities & density */
-	if (smoothfac > 0.0f || pressfac > 0.0f) {
-		HairVertexGrid *vertex_grid = BPH_hair_volume_create_vertex_grid(clmd->sim_parms->voxel_res, gmin, gmax);
-
-		vert = cloth->verts;
-		for (i = 0; i < mvert_num; i++, vert++) {
-			float x[3], v[3];
-
-			if (vert->solver_index < 0) {
-				copy_v3_v3(x, vert->x);
-				copy_v3_v3(v, vert->v);
-			}
-			else {
-				BPH_mass_spring_get_motion_state(data, vert->solver_index, x, v);
-			}
-			BPH_hair_volume_add_vertex(vertex_grid, x, v);
-		}
-		BPH_hair_volume_normalize_vertex_grid(vertex_grid);
-
-		vert = cloth->verts;
-		for (i = 0; i < mvert_num; i++, vert++) {
-			float x[3], v[3], f[3], dfdx[3][3], dfdv[3][3];
-
-			if (vert->solver_index < 0)
-				continue;
-
-			/* calculate volumetric forces */
-			BPH_mass_spring_get_motion_state(data, vert->solver_index, x, v);
-			BPH_hair_volume_vertex_grid_forces(vertex_grid, x, v, smoothfac, pressfac, minpress, f, dfdx, dfdv);
-			/* apply on hair data */
-			BPH_mass_spring_force_extern(data, vert->solver_index, f, dfdx, dfdv);
-		}
-
-		BPH_hair_volume_free_vertex_grid(vertex_grid);
-	}
+  ClothSimSettings *parms = clmd->sim_parms;
+  Cloth *cloth = clmd->clothObject;
+  Implicit_Data *data = cloth->implicit;
+  int mvert_num = cloth->mvert_num;
+  ClothVertex *vert;
+
+  /* 2.0f is an experimental value that seems to give good results */
+  float smoothfac = 2.0f * parms->velocity_smooth;
+  float collfac = 2.0f * parms->collider_friction;
+  float pressfac = parms->pressure;
+  float minpress = parms->pressure_threshold;
+  float gmin[3], gmax[3];
+  int i;
+
+  hair_get_boundbox(clmd, gmin, gmax);
+
+  /* gather velocities & density */
+  if (smoothfac > 0.0f || pressfac > 0.0f) {
+    HairVertexGrid *vertex_grid = BPH_hair_volume_create_vertex_grid(clmd->sim_parms->voxel_res, gmin, gmax);
+
+    vert = cloth->verts;
+    for (i = 0; i < mvert_num; i++, vert++) {
+      float x[3], v[3];
+
+      if (vert->solver_index < 0) {
+        copy_v3_v3(x, vert->x);
+        copy_v3_v3(v, vert->v);
+      }
+      else {
+        BPH_mass_spring_get_motion_state(data, vert->solver_index, x, v);
+      }
+      BPH_hair_volume_add_vertex(vertex_grid, x, v);
+    }
+    BPH_hair_volume_normalize_vertex_grid(vertex_grid);
+
+    vert = cloth->verts;
+    for (i = 0; i < mvert_num; i++, vert++) {
+      float x[3], v[3], f[3], dfdx[3][3], dfdv[3][3];
+
+      if (vert->solver_index < 0)
+        continue;
+
+      /* calculate volumetric forces */
+      BPH_mass_spring_get_motion_state(data, vert->solver_index, x, v);
+      BPH_hair_volume_vertex_grid_forces(vertex_grid, x, v, smoothfac, pressfac, minpress, f, dfdx, dfdv);
+      /* apply on hair data */
+      BPH_mass_spring_force_extern(data, vert->solver_index, f, dfdx, dfdv);
+    }
+
+    BPH_hair_volume_free_vertex_grid(vertex_grid);
+  }
 }
 #endif
 
-static void cloth_solve_collisions(Depsgraph *depsgraph, Object *ob, ClothModifierData *clmd, float step, float dt)
+static void cloth_solve_collisions(
+    Depsgraph *depsgraph, Object *ob, ClothModifierData *clmd, float step, float dt)
 {
-	Cloth *cloth = clmd->clothObject;
-	Implicit_Data *id = cloth->implicit;
-	ClothVertex *verts = cloth->verts;
-	int mvert_num = cloth->mvert_num;
-	const float time_multiplier = 1.0f / (clmd->sim_parms->dt * clmd->sim_parms->timescale);
-	int i;
-
-	if (!(clmd->coll_parms->flags & (CLOTH_COLLSETTINGS_FLAG_ENABLED | CLOTH_COLLSETTINGS_FLAG_SELF)))
-		return;
-
-	if (!clmd->clothObject->bvhtree)
-		return;
-
-	BPH_mass_spring_solve_positions(id, dt);
-
-	/* Update verts to current positions. */
-	for (i = 0; i < mvert_num; i++) {
-		BPH_mass_spring_get_new_position(id, i, verts[i].tx);
-
-		sub_v3_v3v3(verts[i].tv, verts[i].tx, verts[i].txold);
-		zero_v3(verts[i].dcvel);
-	}
-
-	if (cloth_bvh_collision(depsgraph, ob, clmd, step / clmd->sim_parms->timescale, dt / clmd->sim_parms->timescale)) {
-		for (i = 0; i < mvert_num; i++) {
-			if ((clmd->sim_parms->vgroup_mass > 0) && (verts[i].flags & CLOTH_VERT_FLAG_PINNED))
-				continue;
-
-			BPH_mass_spring_get_new_velocity(id, i, verts[i].tv);
-			madd_v3_v3fl(verts[i].tv, verts[i].dcvel, time_multiplier);
-			BPH_mass_spring_set_new_velocity(id, i, verts[i].tv);
-		}
-	}
+  Cloth *cloth = clmd->clothObject;
+  Implicit_Data *id = cloth->implicit;
+  ClothVertex *verts = cloth->verts;
+  int mvert_num = cloth->mvert_num;
+  const float time_multiplier = 1.0f / (clmd->sim_parms->dt * clmd->sim_parms->timescale);
+  int i;
+
+  if (!(clmd->coll_parms->flags &
+        (CLOTH_COLLSETTINGS_FLAG_ENABLED | CLOTH_COLLSETTINGS_FLAG_SELF)))
+    return;
+
+  if (!clmd->clothObject->bvhtree)
+    return;
+
+  BPH_mass_spring_solve_positions(id, dt);
+
+  /* Update verts to current positions. */
+  for (i = 0; i < mvert_num; i++) {
+    BPH_mass_spring_get_new_position(id, i, verts[i].tx);
+
+    sub_v3_v3v3(verts[i].tv, verts[i].tx, verts[i].txold);
+    zero_v3(verts[i].dcvel);
+  }
+
+  if (cloth_bvh_collision(depsgraph,
+                          ob,
+                          clmd,
+                          step / clmd->sim_parms->timescale,
+                          dt / clmd->sim_parms->timescale)) {
+    for (i = 0; i < mvert_num; i++) {
+      if ((clmd->sim_parms->vgroup_mass > 0) && (verts[i].flags & CLOTH_VERT_FLAG_PINNED))
+        continue;
+
+      BPH_mass_spring_get_new_velocity(id, i, verts[i].tv);
+      madd_v3_v3fl(verts[i].tv, verts[i].dcvel, time_multiplier);
+      BPH_mass_spring_set_new_velocity(id, i, verts[i].tv);
+    }
+  }
 }
 
 static void cloth_clear_result(ClothModifierData *clmd)
 {
-	ClothSolverResult *sres = clmd->solver_result;
+  ClothSolverResult *sres = clmd->solver_result;
 
-	sres->status = 0;
-	sres->max_error = sres->min_error = sres->avg_error = 0.0f;
-	sres->max_iterations = sres->min_iterations = 0;
-	sres->avg_iterations = 0.0f;
+  sres->status = 0;
+  sres->max_error = sres->min_error = sres->avg_error = 0.0f;
+  sres->max_iterations = sres->min_iterations = 0;
+  sres->avg_iterations = 0.0f;
 }
 
 static void cloth_record_result(ClothModifierData *clmd, ImplicitSolverResult *result, float dt)
 {
-	ClothSolverResult *sres = clmd->solver_result;
-
-	if (sres->status) {     /* already initialized ? */
-		/* error only makes sense for successful iterations */
-		if (result->status == BPH_SOLVER_SUCCESS) {
-			sres->min_error = min_ff(sres->min_error, result->error);
-			sres->max_error = max_ff(sres->max_error, result->error);
-			sres->avg_error += result->error * dt;
-		}
-
-		sres->min_iterations = min_ii(sres->min_iterations, result->iterations);
-		sres->max_iterations = max_ii(sres->max_iterations, result->iterations);
-		sres->avg_iterations += (float)result->iterations * dt;
-	}
-	else {
-		/* error only makes sense for successful iterations */
-		if (result->status == BPH_SOLVER_SUCCESS) {
-			sres->min_error = sres->max_error = result->error;
-			sres->avg_error += result->error * dt;
-		}
-
-		sres->min_iterations = sres->max_iterations  = result->iterations;
-		sres->avg_iterations += (float)result->iterations * dt;
-	}
-
-	sres->status |= result->status;
+  ClothSolverResult *sres = clmd->solver_result;
+
+  if (sres->status) { /* already initialized ? */
+    /* error only makes sense for successful iterations */
+    if (result->status == BPH_SOLVER_SUCCESS) {
+      sres->min_error = min_ff(sres->min_error, result->error);
+      sres->max_error = max_ff(sres->max_error, result->error);
+      sres->avg_error += result->error * dt;
+    }
+
+    sres->min_iterations = min_ii(sres->min_iterations, result->iterations);
+    sres->max_iterations = max_ii(sres->max_iterations, result->iterations);
+    sres->avg_iterations += (float)result->iterations * dt;
+  }
+  else {
+    /* error only makes sense for successful iterations */
+    if (result->status == BPH_SOLVER_SUCCESS) {
+      sres->min_error = sres->max_error = result->error;
+      sres->avg_error += result->error * dt;
+    }
+
+    sres->min_iterations = sres->max_iterations = result->iterations;
+    sres->avg_iterations += (float)result->iterations * dt;
+  }
+
+  sres->status |= result->status;
 }
 
-int BPH_cloth_solve(Depsgraph *depsgraph, Object *ob, float frame, ClothModifierData *clmd, ListBase *effectors)
+int BPH_cloth_solve(
+    Depsgraph *depsgraph, Object *ob, float frame, ClothModifierData *clmd, ListBase *effectors)
 {
-	/* Hair currently is a cloth sim in disguise ...
-	 * Collision detection and volumetrics work differently then.
-	 * Bad design, TODO
-	 */
-	Scene *scene = DEG_get_evaluated_scene(depsgraph);
-	const bool is_hair = (clmd->hairdata != NULL);
-
-	unsigned int i = 0;
-	float step = 0.0f, tf = clmd->sim_parms->timescale;
-	Cloth *cloth = clmd->clothObject;
-	ClothVertex *verts = cloth->verts /*, *cv*/;
-	unsigned int mvert_num = cloth->mvert_num;
-	float dt = clmd->sim_parms->dt * clmd->sim_parms->timescale;
-	Implicit_Data *id = cloth->implicit;
-	ColliderContacts *contacts = NULL;
-	int totcolliders = 0;
-
-	BKE_sim_debug_data_clear_category("collision");
-
-	if (!clmd->solver_result)
-		clmd->solver_result = (ClothSolverResult *)MEM_callocN(sizeof(ClothSolverResult), "cloth solver result");
-	cloth_clear_result(clmd);
-
-	if (clmd->sim_parms->vgroup_mass > 0) { /* Do goal stuff. */
-		for (i = 0; i < mvert_num; i++) {
-			// update velocities with constrained velocities from pinned verts
-			if (verts[i].flags & CLOTH_VERT_FLAG_PINNED) {
-				float v[3];
-				sub_v3_v3v3(v, verts[i].xconst, verts[i].xold);
-				// mul_v3_fl(v, clmd->sim_parms->stepsPerFrame);
-				/* divide by time_scale to prevent constrained velocities from being multiplied */
-				mul_v3_fl(v, 1.0f / clmd->sim_parms->time_scale);
-				BPH_mass_spring_set_velocity(id, i, v);
-			}
-		}
-	}
-
-	while (step < tf) {
-		ImplicitSolverResult result;
-
-		if (is_hair) {
-			/* determine contact points */
-			if (clmd->coll_parms->flags & CLOTH_COLLSETTINGS_FLAG_ENABLED) {
-				cloth_find_point_contacts(depsgraph, ob, clmd, 0.0f, tf, &contacts, &totcolliders);
-			}
-
-			/* setup vertex constraints for pinned vertices and contacts */
-			cloth_setup_constraints(clmd, contacts, totcolliders, dt);
-		}
-		else {
-			/* setup vertex constraints for pinned vertices */
-			cloth_setup_constraints(clmd, NULL, 0, dt);
-		}
-
-		/* initialize forces to zero */
-		BPH_mass_spring_clear_forces(id);
-
-		// calculate forces
-		cloth_calc_force(scene, clmd, frame, effectors, step);
-
-		// calculate new velocity and position
-		BPH_mass_spring_solve_velocities(id, dt, &result);
-		cloth_record_result(clmd, &result, dt);
-
-		/* Calculate collision impulses. */
-		if (!is_hair) {
-			cloth_solve_collisions(depsgraph, ob, clmd, step, dt);
-		}
-
-		if (is_hair) {
-			cloth_continuum_step(clmd, dt);
-		}
-
-		BPH_mass_spring_solve_positions(id, dt);
-		BPH_mass_spring_apply_result(id);
-
-		/* move pinned verts to correct position */
-		for (i = 0; i < mvert_num; i++) {
-			if (clmd->sim_parms->vgroup_mass > 0) {
-				if (verts[i].flags & CLOTH_VERT_FLAG_PINNED) {
-					float x[3];
-					/* divide by time_scale to prevent pinned vertices' delta locations from being multiplied */
-					interp_v3_v3v3(x, verts[i].xold, verts[i].xconst, (step + dt) / clmd->sim_parms->time_scale);
-					BPH_mass_spring_set_position(id, i, x);
-				}
-			}
-
-			BPH_mass_spring_get_motion_state(id, i, verts[i].txold, NULL);
-		}
-
-		/* free contact points */
-		if (contacts) {
-			cloth_free_contacts(contacts, totcolliders);
-		}
-
-		step += dt;
-	}
-
-	/* copy results back to cloth data */
-	for (i = 0; i < mvert_num; i++) {
-		BPH_mass_spring_get_motion_state(id, i, verts[i].x, verts[i].v);
-		copy_v3_v3(verts[i].txold, verts[i].x);
-	}
-
-	return 1;
+  /* Hair currently is a cloth sim in disguise ...
+   * Collision detection and volumetrics work differently then.
+   * Bad design, TODO
+   */
+  Scene *scene = DEG_get_evaluated_scene(depsgraph);
+  const bool is_hair = (clmd->hairdata != NULL);
+
+  unsigned int i = 0;
+  float step = 0.0f, tf = clmd->sim_parms->timescale;
+  Cloth *cloth = clmd->clothObject;
+  ClothVertex *verts = cloth->verts /*, *cv*/;
+  unsigned int mvert_num = cloth->mvert_num;
+  float dt = clmd->sim_parms->dt * clmd->sim_parms->timescale;
+  Implicit_Data *id = cloth->implicit;
+  ColliderContacts *contacts = NULL;
+  int totcolliders = 0;
+
+  BKE_sim_debug_data_clear_category("collision");
+
+  if (!clmd->solver_result)
+    clmd->solver_result = (ClothSolverResult *)MEM_callocN(sizeof(ClothSolverResult),
+                                                           "cloth solver result");
+  cloth_clear_result(clmd);
+
+  if (clmd->sim_parms->vgroup_mass > 0) { /* Do goal stuff. */
+    for (i = 0; i < mvert_num; i++) {
+      // update velocities with constrained velocities from pinned verts
+      if (verts[i].flags & CLOTH_VERT_FLAG_PINNED) {
+        float v[3];
+        sub_v3_v3v3(v, verts[i].xconst, verts[i].xold);
+        // mul_v3_fl(v, clmd->sim_parms->stepsPerFrame);
+        /* divide by time_scale to prevent constrained velocities from being multiplied */
+        mul_v3_fl(v, 1.0f / clmd->sim_parms->time_scale);
+        BPH_mass_spring_set_velocity(id, i, v);
+      }
+    }
+  }
+
+  while (step < tf) {
+    ImplicitSolverResult result;
+
+    if (is_hair) {
+      /* determine contact points */
+      if (clmd->coll_parms->flags & CLOTH_COLLSETTINGS_FLAG_ENABLED) {
+        cloth_find_point_contacts(depsgraph, ob, clmd, 0.0f, tf, &contacts, &totcolliders);
+      }
+
+      /* setup vertex constraints for pinned vertices and contacts */
+      cloth_setup_constraints(clmd, contacts, totcolliders, dt);
+    }
+    else {
+      /* setup vertex constraints for pinned vertices */
+      cloth_setup_constraints(clmd, NULL, 0, dt);
+    }
+
+    /* initialize forces to zero */
+    BPH_mass_spring_clear_forces(id);
+
+    // calculate forces
+    cloth_calc_force(scene, clmd, frame, effectors, step);
+
+    // calculate new velocity and position
+    BPH_mass_spring_solve_velocities(id, dt, &result);
+    cloth_record_result(clmd, &result, dt);
+
+    /* Calculate collision impulses. */
+    if (!is_hair) {
+      cloth_solve_collisions(depsgraph, ob, clmd, step, dt);
+    }
+
+    if (is_hair) {
+      cloth_continuum_step(clmd, dt);
+    }
+
+    BPH_mass_spring_solve_positions(id, dt);
+    BPH_mass_spring_apply_result(id);
+
+    /* move pinned verts to correct position */
+    for (i = 0; i < mvert_num; i++) {
+      if (clmd->sim_parms->vgroup_mass > 0) {
+        if (verts[i].flags & CLOTH_VERT_FLAG_PINNED) {
+          float x[3];
+          /* divide by time_scale to prevent pinned vertices' delta locations from being multiplied */
+          interp_v3_v3v3(
+              x, verts[i].xold, verts[i].xconst, (step + dt) / clmd->sim_parms->time_scale);
+          BPH_mass_spring_set_position(id, i, x);
+        }
+      }
+
+      BPH_mass_spring_get_motion_state(id, i, verts[i].txold, NULL);
+    }
+
+    /* free contact points */
+    if (contacts) {
+      cloth_free_contacts(contacts, totcolliders);
+    }
+
+    step += dt;
+  }
+
+  /* copy results back to cloth data */
+  for (i = 0; i < mvert_num; i++) {
+    BPH_mass_spring_get_motion_state(id, i, verts[i].x, verts[i].v);
+    copy_v3_v3(verts[i].txold, verts[i].x);
+  }
+
+  return 1;
 }
diff --git a/source/blender/physics/intern/ConstrainedConjugateGradient.h b/source/blender/physics/intern/ConstrainedConjugateGradient.h
index e5cdcb068c8..0d361f98f4e 100644
--- a/source/blender/physics/intern/ConstrainedConjugateGradient.h
+++ b/source/blender/physics/intern/ConstrainedConjugateGradient.h
@@ -35,119 +35,126 @@ namespace internal {
   * \param iters: On input the max number of iteration, on output the number of performed iterations.
   * \param tol_error: On input the tolerance error, on output an estimation of the relative error.
   */
-template<typename MatrixType, typename Rhs, typename Dest, typename FilterMatrixType, typename Preconditioner>
-EIGEN_DONT_INLINE
-void constrained_conjugate_gradient(const MatrixType& mat, const Rhs& rhs, Dest& x,
-                                    const FilterMatrixType &filter,
-                                    const Preconditioner& precond, int& iters,
-                                    typename Dest::RealScalar& tol_error)
+template<typename MatrixType,
+         typename Rhs,
+         typename Dest,
+         typename FilterMatrixType,
+         typename Preconditioner>
+EIGEN_DONT_INLINE void constrained_conjugate_gradient(const MatrixType &mat,
+                                                      const Rhs &rhs,
+                                                      Dest &x,
+                                                      const FilterMatrixType &filter,
+                                                      const Preconditioner &precond,
+                                                      int &iters,
+                                                      typename Dest::RealScalar &tol_error)
 {
-  using std::sqrt;
   using std::abs;
+  using std::sqrt;
   typedef typename Dest::RealScalar RealScalar;
   typedef typename Dest::Scalar Scalar;
-  typedef Matrix<Scalar,Dynamic,1> VectorType;
+  typedef Matrix<Scalar, Dynamic, 1> VectorType;
 
   RealScalar tol = tol_error;
   int maxIters = iters;
 
   int n = mat.cols();
 
-  VectorType residual = filter * (rhs - mat * x); //initial residual
+  VectorType residual = filter * (rhs - mat * x);  //initial residual
 
   RealScalar rhsNorm2 = (filter * rhs).squaredNorm();
-  if(rhsNorm2 == 0)
-  {
+  if (rhsNorm2 == 0) {
     /* XXX TODO set constrained result here */
     x.setZero();
     iters = 0;
     tol_error = 0;
     return;
   }
-  RealScalar threshold = tol*tol*rhsNorm2;
+  RealScalar threshold = tol * tol * rhsNorm2;
   RealScalar residualNorm2 = residual.squaredNorm();
-  if (residualNorm2 < threshold)
-  {
+  if (residualNorm2 < threshold) {
     iters = 0;
     tol_error = sqrt(residualNorm2 / rhsNorm2);
     return;
   }
 
   VectorType p(n);
-  p = filter * precond.solve(residual);          //initial search direction
+  p = filter * precond.solve(residual);  //initial search direction
 
   VectorType z(n), tmp(n);
-  RealScalar absNew = numext::real(residual.dot(p));  // the square of the absolute value of r scaled by invM
+  RealScalar absNew = numext::real(
+      residual.dot(p));  // the square of the absolute value of r scaled by invM
   int i = 0;
-  while(i < maxIters)
-  {
-    tmp.noalias() = filter * (mat * p);            // the bottleneck of the algorithm
+  while (i < maxIters) {
+    tmp.noalias() = filter * (mat * p);  // the bottleneck of the algorithm
 
-    Scalar alpha = absNew / p.dot(tmp);         // the amount we travel on dir
-    x += alpha * p;                             // update solution
-    residual -= alpha * tmp;                    // update residue
+    Scalar alpha = absNew / p.dot(tmp);  // the amount we travel on dir
+    x += alpha * p;                      // update solution
+    residual -= alpha * tmp;             // update residue
 
     residualNorm2 = residual.squaredNorm();
-    if(residualNorm2 < threshold)
+    if (residualNorm2 < threshold)
       break;
 
-    z = precond.solve(residual);                // approximately solve for "A z = residual"
+    z = precond.solve(residual);  // approximately solve for "A z = residual"
 
     RealScalar absOld = absNew;
-    absNew = numext::real(residual.dot(z));     // update the absolute value of r
-    RealScalar beta = absNew / absOld;          // calculate the Gram-Schmidt value used to create the new search direction
-    p = filter * (z + beta * p);             // update search direction
+    absNew = numext::real(residual.dot(z));  // update the absolute value of r
+    RealScalar beta =
+        absNew /
+        absOld;  // calculate the Gram-Schmidt value used to create the new search direction
+    p = filter * (z + beta * p);  // update search direction
     i++;
   }
   tol_error = sqrt(residualNorm2 / rhsNorm2);
   iters = i;
 }
 
-}
+}  // namespace internal
 
 #if 0 /* unused */
 template<typename MatrixType>
 struct MatrixFilter
 {
-	MatrixFilter() :
-	    m_cmat(NULL)
-	{
-	}
+  MatrixFilter() :
+      m_cmat(NULL)
+  {
+  }
 
-	MatrixFilter(const MatrixType &cmat) :
-	    m_cmat(&cmat)
-	{
-	}
+  MatrixFilter(const MatrixType &cmat) :
+      m_cmat(&cmat)
+  {
+  }
 
-	void setMatrix(const MatrixType &cmat) { m_cmat = &cmat; }
+  void setMatrix(const MatrixType &cmat) { m_cmat = &cmat; }
 
-	template <typename VectorType>
-	void apply(VectorType v) const
-	{
-		v = (*m_cmat) * v;
-	}
+  template <typename VectorType>
+  void apply(VectorType v) const
+  {
+    v = (*m_cmat) * v;
+  }
 
 protected:
-	const MatrixType *m_cmat;
+  const MatrixType *m_cmat;
 };
 #endif
 
-template< typename _MatrixType, int _UpLo=Lower,
-          typename _FilterMatrixType = _MatrixType,
-          typename _Preconditioner = DiagonalPreconditioner<typename _MatrixType::Scalar> >
+template<typename _MatrixType,
+         int _UpLo = Lower,
+         typename _FilterMatrixType = _MatrixType,
+         typename _Preconditioner = DiagonalPreconditioner<typename _MatrixType::Scalar>>
 class ConstrainedConjugateGradient;
 
 namespace internal {
 
-template< typename _MatrixType, int _UpLo, typename _FilterMatrixType, typename _Preconditioner>
-struct traits<ConstrainedConjugateGradient<_MatrixType,_UpLo,_FilterMatrixType,_Preconditioner> >
-{
+template<typename _MatrixType, int _UpLo, typename _FilterMatrixType, typename _Preconditioner>
+struct traits<
+    ConstrainedConjugateGradient<_MatrixType, _UpLo, _FilterMatrixType, _Preconditioner>> {
   typedef _MatrixType MatrixType;
   typedef _FilterMatrixType FilterMatrixType;
   typedef _Preconditioner Preconditioner;
 };
 
-}
+}  // namespace internal
 
 /** \ingroup IterativeLinearSolvers_Module
   * \brief A conjugate gradient solver for sparse self-adjoint problems with additional constraints
@@ -197,16 +204,18 @@ struct traits<ConstrainedConjugateGradient<_MatrixType,_UpLo,_FilterMatrixType,_
   *
   * \sa class SimplicialCholesky, DiagonalPreconditioner, IdentityPreconditioner
   */
-template< typename _MatrixType, int _UpLo, typename _FilterMatrixType, typename _Preconditioner>
-class ConstrainedConjugateGradient : public IterativeSolverBase<ConstrainedConjugateGradient<_MatrixType,_UpLo,_FilterMatrixType,_Preconditioner> >
-{
+template<typename _MatrixType, int _UpLo, typename _FilterMatrixType, typename _Preconditioner>
+class ConstrainedConjugateGradient
+    : public IterativeSolverBase<
+          ConstrainedConjugateGradient<_MatrixType, _UpLo, _FilterMatrixType, _Preconditioner>> {
   typedef IterativeSolverBase<ConstrainedConjugateGradient> Base;
-  using Base::mp_matrix;
   using Base::m_error;
-  using Base::m_iterations;
   using Base::m_info;
   using Base::m_isInitialized;
-public:
+  using Base::m_iterations;
+  using Base::mp_matrix;
+
+ public:
   typedef _MatrixType MatrixType;
   typedef typename MatrixType::Scalar Scalar;
   typedef typename MatrixType::Index Index;
@@ -214,14 +223,13 @@ public:
   typedef _FilterMatrixType FilterMatrixType;
   typedef _Preconditioner Preconditioner;
 
-  enum {
-    UpLo = _UpLo
-  };
-
-public:
+  enum { UpLo = _UpLo };
 
+ public:
   /** Default constructor. */
-  ConstrainedConjugateGradient() : Base() {}
+  ConstrainedConjugateGradient() : Base()
+  {
+  }
 
   /** Initialize the solver with matrix \a A for further \c Ax=b solving.
     *
@@ -233,44 +241,58 @@ public:
     * this class becomes invalid. Call compute() to update it with the new
     * matrix A, or modify a copy of A.
     */
-  ConstrainedConjugateGradient(const MatrixType& A) : Base(A) {}
+  ConstrainedConjugateGradient(const MatrixType &A) : Base(A)
+  {
+  }
 
-  ~ConstrainedConjugateGradient() {}
+  ~ConstrainedConjugateGradient()
+  {
+  }
 
-  FilterMatrixType &filter() { return m_filter; }
-  const FilterMatrixType &filter() const { return m_filter; }
+  FilterMatrixType &filter()
+  {
+    return m_filter;
+  }
+  const FilterMatrixType &filter() const
+  {
+    return m_filter;
+  }
 
   /** \returns the solution x of \f$ A x = b \f$ using the current decomposition of A
     * \a x0 as an initial solution.
     *
     * \sa compute()
     */
-  template<typename Rhs,typename Guess>
+  template<typename Rhs, typename Guess>
   inline const internal::solve_retval_with_guess<ConstrainedConjugateGradient, Rhs, Guess>
-  solveWithGuess(const MatrixBase<Rhs>& b, const Guess& x0) const
+  solveWithGuess(const MatrixBase<Rhs> &b, const Guess &x0) const
   {
     eigen_assert(m_isInitialized && "ConjugateGradient is not initialized.");
-    eigen_assert(Base::rows()==b.rows()
-              && "ConjugateGradient::solve(): invalid number of rows of the right hand side matrix b");
-    return internal::solve_retval_with_guess
-            <ConstrainedConjugateGradient, Rhs, Guess>(*this, b.derived(), x0);
+    eigen_assert(
+        Base::rows() == b.rows() &&
+        "ConjugateGradient::solve(): invalid number of rows of the right hand side matrix b");
+    return internal::solve_retval_with_guess<ConstrainedConjugateGradient, Rhs, Guess>(
+        *this, b.derived(), x0);
   }
 
   /** \internal */
-  template<typename Rhs,typename Dest>
-  void _solveWithGuess(const Rhs& b, Dest& x) const
+  template<typename Rhs, typename Dest> void _solveWithGuess(const Rhs &b, Dest &x) const
   {
     m_iterations = Base::maxIterations();
     m_error = Base::m_tolerance;
 
-    for(int j=0; j<b.cols(); ++j)
-    {
+    for (int j = 0; j < b.cols(); ++j) {
       m_iterations = Base::maxIterations();
       m_error = Base::m_tolerance;
 
-      typename Dest::ColXpr xj(x,j);
-      internal::constrained_conjugate_gradient(mp_matrix->template selfadjointView<UpLo>(), b.col(j), xj, m_filter,
-	                                           Base::m_preconditioner, m_iterations, m_error);
+      typename Dest::ColXpr xj(x, j);
+      internal::constrained_conjugate_gradient(mp_matrix->template selfadjointView<UpLo>(),
+                                               b.col(j),
+                                               xj,
+                                               m_filter,
+                                               Base::m_preconditioner,
+                                               m_iterations,
+                                               m_error);
     }
 
     m_isInitialized = true;
@@ -278,35 +300,34 @@ public:
   }
 
   /** \internal */
-  template<typename Rhs,typename Dest>
-  void _solve(const Rhs& b, Dest& x) const
+  template<typename Rhs, typename Dest> void _solve(const Rhs &b, Dest &x) const
   {
     x.setOnes();
-    _solveWithGuess(b,x);
+    _solveWithGuess(b, x);
   }
 
-protected:
+ protected:
   FilterMatrixType m_filter;
 };
 
-
 namespace internal {
 
 template<typename _MatrixType, int _UpLo, typename _Filter, typename _Preconditioner, typename Rhs>
-struct solve_retval<ConstrainedConjugateGradient<_MatrixType,_UpLo,_Filter,_Preconditioner>, Rhs>
-  : solve_retval_base<ConstrainedConjugateGradient<_MatrixType,_UpLo,_Filter,_Preconditioner>, Rhs>
-{
-  typedef ConstrainedConjugateGradient<_MatrixType,_UpLo,_Filter,_Preconditioner> Dec;
-  EIGEN_MAKE_SOLVE_HELPERS(Dec,Rhs)
-
-  template<typename Dest> void evalTo(Dest& dst) const
+struct solve_retval<ConstrainedConjugateGradient<_MatrixType, _UpLo, _Filter, _Preconditioner>,
+                    Rhs>
+    : solve_retval_base<ConstrainedConjugateGradient<_MatrixType, _UpLo, _Filter, _Preconditioner>,
+                        Rhs> {
+  typedef ConstrainedConjugateGradient<_MatrixType, _UpLo, _Filter, _Preconditioner> Dec;
+  EIGEN_MAKE_SOLVE_HELPERS(Dec, Rhs)
+
+  template<typename Dest> void evalTo(Dest &dst) const
   {
-    dec()._solve(rhs(),dst);
+    dec()._solve(rhs(), dst);
   }
 };
 
-} // end namespace internal
+}  // end namespace internal
 
-} // end namespace Eigen
+}  // end namespace Eigen
 
-#endif // __CONSTRAINEDCONJUGATEGRADIENT_H__
+#endif  // __CONSTRAINEDCONJUGATEGRADIENT_H__
diff --git a/source/blender/physics/intern/eigen_utils.h b/source/blender/physics/intern/eigen_utils.h
index 16e1186441f..7d56fe1a608 100644
--- a/source/blender/physics/intern/eigen_utils.h
+++ b/source/blender/physics/intern/eigen_utils.h
@@ -39,69 +39,68 @@
 
 #include "BLI_utildefines.h"
 
-
 typedef float Scalar;
 
 /* slightly extended Eigen vector class
  * with conversion to/from plain C float array
  */
 class Vector3 : public Eigen::Vector3f {
-public:
-	typedef float *ctype;
-
-	Vector3()
-	{
-	}
-
-	Vector3(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			coeffRef(k) = v[k];
-	}
-
-	Vector3& operator =(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			coeffRef(k) = v[k];
-		return *this;
-	}
-
-	operator ctype()
-	{
-		return data();
-	}
+ public:
+  typedef float *ctype;
+
+  Vector3()
+  {
+  }
+
+  Vector3(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      coeffRef(k) = v[k];
+  }
+
+  Vector3 &operator=(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      coeffRef(k) = v[k];
+    return *this;
+  }
+
+  operator ctype()
+  {
+    return data();
+  }
 };
 
 /* slightly extended Eigen matrix class
  * with conversion to/from plain C float array
  */
 class Matrix3 : public Eigen::Matrix3f {
-public:
-	typedef float (*ctype)[3];
-
-	Matrix3()
-	{
-	}
-
-	Matrix3(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				coeffRef(l, k) = v[k][l];
-	}
-
-	Matrix3& operator =(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				coeffRef(l, k) = v[k][l];
-		return *this;
-	}
-
-	operator ctype()
-	{
-		return (ctype)data();
-	}
+ public:
+  typedef float (*ctype)[3];
+
+  Matrix3()
+  {
+  }
+
+  Matrix3(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        coeffRef(l, k) = v[k][l];
+  }
+
+  Matrix3 &operator=(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        coeffRef(l, k) = v[k][l];
+    return *this;
+  }
+
+  operator ctype()
+  {
+    return (ctype)data();
+  }
 };
 
 typedef Eigen::VectorXf lVector;
@@ -110,29 +109,28 @@ typedef Eigen::VectorXf lVector;
  * providing 3-float block access for blenlib math functions
  */
 class lVector3f : public Eigen::VectorXf {
-public:
-	typedef Eigen::VectorXf base_t;
-
-	lVector3f()
-	{
-	}
-
-	template <typename T>
-	lVector3f& operator =(T rhs)
-	{
-		base_t::operator=(rhs);
-		return *this;
-	}
-
-	float *v3(int vertex)
-	{
-		return &coeffRef(3 * vertex);
-	}
-
-	const float *v3(int vertex) const
-	{
-		return &coeffRef(3 * vertex);
-	}
+ public:
+  typedef Eigen::VectorXf base_t;
+
+  lVector3f()
+  {
+  }
+
+  template<typename T> lVector3f &operator=(T rhs)
+  {
+    base_t::operator=(rhs);
+    return *this;
+  }
+
+  float *v3(int vertex)
+  {
+    return &coeffRef(3 * vertex);
+  }
+
+  const float *v3(int vertex) const
+  {
+    return &coeffRef(3 * vertex);
+  }
 };
 
 typedef Eigen::Triplet<Scalar> Triplet;
@@ -146,77 +144,78 @@ typedef Eigen::SparseMatrix<Scalar> lMatrix;
  * After all elements have been defined using the set() method, the actual matrix can be filled using construct().
  */
 struct lMatrix3fCtor {
-	lMatrix3fCtor()
-	{
-	}
-
-	void reset()
-	{
-		m_trips.clear();
-	}
-
-	void reserve(int numverts)
-	{
-		/* reserve for diagonal entries */
-		m_trips.reserve(numverts * 9);
-	}
-
-	void add(int i, int j, const Matrix3 &m)
-	{
-		i *= 3;
-		j *= 3;
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				m_trips.push_back(Triplet(i + k, j + l, m.coeff(l, k)));
-	}
-
-	void sub(int i, int j, const Matrix3 &m)
-	{
-		i *= 3;
-		j *= 3;
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				m_trips.push_back(Triplet(i + k, j + l, -m.coeff(l, k)));
-	}
-
-	inline void construct(lMatrix &m)
-	{
-		m.setFromTriplets(m_trips.begin(), m_trips.end());
-		m_trips.clear();
-	}
-
-private:
-	TripletList m_trips;
+  lMatrix3fCtor()
+  {
+  }
+
+  void reset()
+  {
+    m_trips.clear();
+  }
+
+  void reserve(int numverts)
+  {
+    /* reserve for diagonal entries */
+    m_trips.reserve(numverts * 9);
+  }
+
+  void add(int i, int j, const Matrix3 &m)
+  {
+    i *= 3;
+    j *= 3;
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        m_trips.push_back(Triplet(i + k, j + l, m.coeff(l, k)));
+  }
+
+  void sub(int i, int j, const Matrix3 &m)
+  {
+    i *= 3;
+    j *= 3;
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        m_trips.push_back(Triplet(i + k, j + l, -m.coeff(l, k)));
+  }
+
+  inline void construct(lMatrix &m)
+  {
+    m.setFromTriplets(m_trips.begin(), m_trips.end());
+    m_trips.clear();
+  }
+
+ private:
+  TripletList m_trips;
 };
 
-typedef Eigen::ConjugateGradient<lMatrix, Eigen::Lower, Eigen::DiagonalPreconditioner<Scalar> > ConjugateGradient;
+typedef Eigen::ConjugateGradient<lMatrix, Eigen::Lower, Eigen::DiagonalPreconditioner<Scalar>>
+    ConjugateGradient;
 
 using Eigen::ComputationInfo;
 
 BLI_INLINE void print_lvector(const lVector3f &v)
 {
-	for (int i = 0; i < v.rows(); ++i) {
-		if (i > 0 && i % 3 == 0)
-			printf("\n");
+  for (int i = 0; i < v.rows(); ++i) {
+    if (i > 0 && i % 3 == 0)
+      printf("\n");
 
-		printf("%f,\n", v[i]);
-	}
+    printf("%f,\n", v[i]);
+  }
 }
 
 BLI_INLINE void print_lmatrix(const lMatrix &m)
 {
-	for (int j = 0; j < m.rows(); ++j) {
-		if (j > 0 && j % 3 == 0)
-			printf("\n");
-
-		for (int i = 0; i < m.cols(); ++i) {
-			if (i > 0 && i % 3 == 0)
-				printf("  ");
-
-			implicit_print_matrix_elem(m.coeff(j, i));
-		}
-		printf("\n");
-	}
+  for (int j = 0; j < m.rows(); ++j) {
+    if (j > 0 && j % 3 == 0)
+      printf("\n");
+
+    for (int i = 0; i < m.cols(); ++i) {
+      if (i > 0 && i % 3 == 0)
+        printf("  ");
+
+      implicit_print_matrix_elem(m.coeff(j, i));
+    }
+    printf("\n");
+  }
 }
 
 #endif
diff --git a/source/blender/physics/intern/hair_volume.cpp b/source/blender/physics/intern/hair_volume.cpp
index 0eb26934b5d..878f055af01 100644
--- a/source/blender/physics/intern/hair_volume.cpp
+++ b/source/blender/physics/intern/hair_volume.cpp
@@ -57,282 +57,335 @@ static float I[3][3] = {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}};
 
 BLI_INLINE int floor_int(float value)
 {
-	return value > 0.0f ? (int)value : ((int)value) - 1;
+  return value > 0.0f ? (int)value : ((int)value) - 1;
 }
 
 BLI_INLINE float floor_mod(float value)
 {
-	return value - floorf(value);
+  return value - floorf(value);
 }
 
 BLI_INLINE int hair_grid_size(const int res[3])
 {
-	return res[0] * res[1] * res[2];
+  return res[0] * res[1] * res[2];
 }
 
 typedef struct HairGridVert {
-	int samples;
-	float velocity[3];
-	float density;
+  int samples;
+  float velocity[3];
+  float density;
 
-	float velocity_smooth[3];
+  float velocity_smooth[3];
 } HairGridVert;
 
 typedef struct HairGrid {
-	HairGridVert *verts;
-	int res[3];
-	float gmin[3], gmax[3];
-	float cellsize, inv_cellsize;
+  HairGridVert *verts;
+  int res[3];
+  float gmin[3], gmax[3];
+  float cellsize, inv_cellsize;
 } HairGrid;
 
-#define HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, axis) (min_ii(max_ii( (int)((vec[axis] - gmin[axis]) * scale), 0), res[axis] - 2) )
+#define HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, axis) \
+  (min_ii(max_ii((int)((vec[axis] - gmin[axis]) * scale), 0), res[axis] - 2))
 
-BLI_INLINE int hair_grid_offset(const float vec[3], const int res[3], const float gmin[3], float scale)
+BLI_INLINE int hair_grid_offset(const float vec[3],
+                                const int res[3],
+                                const float gmin[3],
+                                float scale)
 {
-	int i, j, k;
-	i = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 0);
-	j = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 1);
-	k = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 2);
-	return i + (j + k * res[1]) * res[0];
+  int i, j, k;
+  i = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 0);
+  j = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 1);
+  k = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 2);
+  return i + (j + k * res[1]) * res[0];
 }
 
-BLI_INLINE int hair_grid_interp_weights(const int res[3], const float gmin[3], float scale, const float vec[3], float uvw[3])
+BLI_INLINE int hair_grid_interp_weights(
+    const int res[3], const float gmin[3], float scale, const float vec[3], float uvw[3])
 {
-	int i, j, k, offset;
+  int i, j, k, offset;
 
-	i = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 0);
-	j = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 1);
-	k = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 2);
-	offset = i + (j + k * res[1]) * res[0];
+  i = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 0);
+  j = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 1);
+  k = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 2);
+  offset = i + (j + k * res[1]) * res[0];
 
-	uvw[0] = (vec[0] - gmin[0]) * scale - (float)i;
-	uvw[1] = (vec[1] - gmin[1]) * scale - (float)j;
-	uvw[2] = (vec[2] - gmin[2]) * scale - (float)k;
+  uvw[0] = (vec[0] - gmin[0]) * scale - (float)i;
+  uvw[1] = (vec[1] - gmin[1]) * scale - (float)j;
+  uvw[2] = (vec[2] - gmin[2]) * scale - (float)k;
 
-//	BLI_assert(0.0f <= uvw[0] && uvw[0] <= 1.0001f);
-//	BLI_assert(0.0f <= uvw[1] && uvw[1] <= 1.0001f);
-//	BLI_assert(0.0f <= uvw[2] && uvw[2] <= 1.0001f);
+  //  BLI_assert(0.0f <= uvw[0] && uvw[0] <= 1.0001f);
+  //  BLI_assert(0.0f <= uvw[1] && uvw[1] <= 1.0001f);
+  //  BLI_assert(0.0f <= uvw[2] && uvw[2] <= 1.0001f);
 
-	return offset;
+  return offset;
 }
 
-BLI_INLINE void hair_grid_interpolate(
-        const HairGridVert *grid, const int res[3], const float gmin[3], float scale, const float vec[3],
-        float *density, float velocity[3], float vel_smooth[3], float density_gradient[3], float velocity_gradient[3][3])
+BLI_INLINE void hair_grid_interpolate(const HairGridVert *grid,
+                                      const int res[3],
+                                      const float gmin[3],
+                                      float scale,
+                                      const float vec[3],
+                                      float *density,
+                                      float velocity[3],
+                                      float vel_smooth[3],
+                                      float density_gradient[3],
+                                      float velocity_gradient[3][3])
 {
-	HairGridVert data[8];
-	float uvw[3], muvw[3];
-	int res2 = res[1] * res[0];
-	int offset;
-
-	offset = hair_grid_interp_weights(res, gmin, scale, vec, uvw);
-	muvw[0] = 1.0f - uvw[0];
-	muvw[1] = 1.0f - uvw[1];
-	muvw[2] = 1.0f - uvw[2];
-
-	data[0] = grid[offset                    ];
-	data[1] = grid[offset                 + 1];
-	data[2] = grid[offset        + res[0]    ];
-	data[3] = grid[offset        + res[0] + 1];
-	data[4] = grid[offset + res2             ];
-	data[5] = grid[offset + res2          + 1];
-	data[6] = grid[offset + res2 + res[0]    ];
-	data[7] = grid[offset + res2 + res[0] + 1];
-
-	if (density) {
-		*density = muvw[2] * (muvw[1] * (muvw[0] * data[0].density + uvw[0] * data[1].density)  +
-		                       uvw[1] * (muvw[0] * data[2].density + uvw[0] * data[3].density)) +
-		            uvw[2] * (muvw[1] * (muvw[0] * data[4].density + uvw[0] * data[5].density)  +
-		                       uvw[1] * (muvw[0] * data[6].density + uvw[0] * data[7].density));
-	}
-
-	if (velocity) {
-		int k;
-		for (k = 0; k < 3; ++k) {
-			velocity[k] = muvw[2] * (muvw[1] * (muvw[0] * data[0].velocity[k] + uvw[0] * data[1].velocity[k])   +
-			                          uvw[1] * (muvw[0] * data[2].velocity[k] + uvw[0] * data[3].velocity[k]) ) +
-			               uvw[2] * (muvw[1] * (muvw[0] * data[4].velocity[k] + uvw[0] * data[5].velocity[k])   +
-			                          uvw[1] * (muvw[0] * data[6].velocity[k] + uvw[0] * data[7].velocity[k]) );
-		}
-	}
-
-	if (vel_smooth) {
-		int k;
-		for (k = 0; k < 3; ++k) {
-			vel_smooth[k] = muvw[2] * (muvw[1] * (muvw[0] * data[0].velocity_smooth[k] + uvw[0] * data[1].velocity_smooth[k])   +
-			                            uvw[1] * (muvw[0] * data[2].velocity_smooth[k] + uvw[0] * data[3].velocity_smooth[k]) ) +
-			                 uvw[2] * (muvw[1] * (muvw[0] * data[4].velocity_smooth[k] + uvw[0] * data[5].velocity_smooth[k])   +
-			                            uvw[1] * (muvw[0] * data[6].velocity_smooth[k] + uvw[0] * data[7].velocity_smooth[k]) );
-		}
-	}
-
-	if (density_gradient) {
-		density_gradient[0] = muvw[1] * muvw[2] * (data[0].density - data[1].density) +
-		                       uvw[1] * muvw[2] * (data[2].density - data[3].density) +
-		                      muvw[1] *  uvw[2] * (data[4].density - data[5].density) +
-		                       uvw[1] *  uvw[2] * (data[6].density - data[7].density);
-
-		density_gradient[1] = muvw[2] * muvw[0] * (data[0].density - data[2].density) +
-		                       uvw[2] * muvw[0] * (data[4].density - data[6].density) +
-		                      muvw[2] *  uvw[0] * (data[1].density - data[3].density) +
-		                       uvw[2] *  uvw[0] * (data[5].density - data[7].density);
-
-		density_gradient[2] = muvw[2] * muvw[0] * (data[0].density - data[4].density) +
-		                       uvw[2] * muvw[0] * (data[1].density - data[5].density) +
-		                      muvw[2] *  uvw[0] * (data[2].density - data[6].density) +
-		                       uvw[2] *  uvw[0] * (data[3].density - data[7].density);
-	}
-
-	if (velocity_gradient) {
-		/* XXX TODO */
-		zero_m3(velocity_gradient);
-	}
+  HairGridVert data[8];
+  float uvw[3], muvw[3];
+  int res2 = res[1] * res[0];
+  int offset;
+
+  offset = hair_grid_interp_weights(res, gmin, scale, vec, uvw);
+  muvw[0] = 1.0f - uvw[0];
+  muvw[1] = 1.0f - uvw[1];
+  muvw[2] = 1.0f - uvw[2];
+
+  data[0] = grid[offset];
+  data[1] = grid[offset + 1];
+  data[2] = grid[offset + res[0]];
+  data[3] = grid[offset + res[0] + 1];
+  data[4] = grid[offset + res2];
+  data[5] = grid[offset + res2 + 1];
+  data[6] = grid[offset + res2 + res[0]];
+  data[7] = grid[offset + res2 + res[0] + 1];
+
+  if (density) {
+    *density = muvw[2] * (muvw[1] * (muvw[0] * data[0].density + uvw[0] * data[1].density) +
+                          uvw[1] * (muvw[0] * data[2].density + uvw[0] * data[3].density)) +
+               uvw[2] * (muvw[1] * (muvw[0] * data[4].density + uvw[0] * data[5].density) +
+                         uvw[1] * (muvw[0] * data[6].density + uvw[0] * data[7].density));
+  }
+
+  if (velocity) {
+    int k;
+    for (k = 0; k < 3; ++k) {
+      velocity[k] = muvw[2] *
+                        (muvw[1] * (muvw[0] * data[0].velocity[k] + uvw[0] * data[1].velocity[k]) +
+                         uvw[1] * (muvw[0] * data[2].velocity[k] + uvw[0] * data[3].velocity[k])) +
+                    uvw[2] *
+                        (muvw[1] * (muvw[0] * data[4].velocity[k] + uvw[0] * data[5].velocity[k]) +
+                         uvw[1] * (muvw[0] * data[6].velocity[k] + uvw[0] * data[7].velocity[k]));
+    }
+  }
+
+  if (vel_smooth) {
+    int k;
+    for (k = 0; k < 3; ++k) {
+      vel_smooth[k] = muvw[2] * (muvw[1] * (muvw[0] * data[0].velocity_smooth[k] +
+                                            uvw[0] * data[1].velocity_smooth[k]) +
+                                 uvw[1] * (muvw[0] * data[2].velocity_smooth[k] +
+                                           uvw[0] * data[3].velocity_smooth[k])) +
+                      uvw[2] * (muvw[1] * (muvw[0] * data[4].velocity_smooth[k] +
+                                           uvw[0] * data[5].velocity_smooth[k]) +
+                                uvw[1] * (muvw[0] * data[6].velocity_smooth[k] +
+                                          uvw[0] * data[7].velocity_smooth[k]));
+    }
+  }
+
+  if (density_gradient) {
+    density_gradient[0] = muvw[1] * muvw[2] * (data[0].density - data[1].density) +
+                          uvw[1] * muvw[2] * (data[2].density - data[3].density) +
+                          muvw[1] * uvw[2] * (data[4].density - data[5].density) +
+                          uvw[1] * uvw[2] * (data[6].density - data[7].density);
+
+    density_gradient[1] = muvw[2] * muvw[0] * (data[0].density - data[2].density) +
+                          uvw[2] * muvw[0] * (data[4].density - data[6].density) +
+                          muvw[2] * uvw[0] * (data[1].density - data[3].density) +
+                          uvw[2] * uvw[0] * (data[5].density - data[7].density);
+
+    density_gradient[2] = muvw[2] * muvw[0] * (data[0].density - data[4].density) +
+                          uvw[2] * muvw[0] * (data[1].density - data[5].density) +
+                          muvw[2] * uvw[0] * (data[2].density - data[6].density) +
+                          uvw[2] * uvw[0] * (data[3].density - data[7].density);
+  }
+
+  if (velocity_gradient) {
+    /* XXX TODO */
+    zero_m3(velocity_gradient);
+  }
 }
 
-void BPH_hair_volume_vertex_grid_forces(
-        HairGrid *grid, const float x[3], const float v[3],
-        float smoothfac, float pressurefac, float minpressure,
-        float f[3], float dfdx[3][3], float dfdv[3][3])
+void BPH_hair_volume_vertex_grid_forces(HairGrid *grid,
+                                        const float x[3],
+                                        const float v[3],
+                                        float smoothfac,
+                                        float pressurefac,
+                                        float minpressure,
+                                        float f[3],
+                                        float dfdx[3][3],
+                                        float dfdv[3][3])
 {
-	float gdensity, gvelocity[3], ggrad[3], gvelgrad[3][3], gradlen;
-
-	hair_grid_interpolate(grid->verts, grid->res, grid->gmin, grid->inv_cellsize, x, &gdensity, gvelocity, NULL, ggrad, gvelgrad);
-
-	zero_v3(f);
-	sub_v3_v3(gvelocity, v);
-	mul_v3_v3fl(f, gvelocity, smoothfac);
-
-	gradlen = normalize_v3(ggrad) - minpressure;
-	if (gradlen > 0.0f) {
-		mul_v3_fl(ggrad, gradlen);
-		madd_v3_v3fl(f, ggrad, pressurefac);
-	}
-
-	zero_m3(dfdx);
-
-	sub_m3_m3m3(dfdv, gvelgrad, I);
-	mul_m3_fl(dfdv, smoothfac);
+  float gdensity, gvelocity[3], ggrad[3], gvelgrad[3][3], gradlen;
+
+  hair_grid_interpolate(grid->verts,
+                        grid->res,
+                        grid->gmin,
+                        grid->inv_cellsize,
+                        x,
+                        &gdensity,
+                        gvelocity,
+                        NULL,
+                        ggrad,
+                        gvelgrad);
+
+  zero_v3(f);
+  sub_v3_v3(gvelocity, v);
+  mul_v3_v3fl(f, gvelocity, smoothfac);
+
+  gradlen = normalize_v3(ggrad) - minpressure;
+  if (gradlen > 0.0f) {
+    mul_v3_fl(ggrad, gradlen);
+    madd_v3_v3fl(f, ggrad, pressurefac);
+  }
+
+  zero_m3(dfdx);
+
+  sub_m3_m3m3(dfdv, gvelgrad, I);
+  mul_m3_fl(dfdv, smoothfac);
 }
 
-void BPH_hair_volume_grid_interpolate(
-        HairGrid *grid, const float x[3],
-        float *density, float velocity[3], float velocity_smooth[3], float density_gradient[3], float velocity_gradient[3][3])
+void BPH_hair_volume_grid_interpolate(HairGrid *grid,
+                                      const float x[3],
+                                      float *density,
+                                      float velocity[3],
+                                      float velocity_smooth[3],
+                                      float density_gradient[3],
+                                      float velocity_gradient[3][3])
 {
-	hair_grid_interpolate(grid->verts, grid->res, grid->gmin, grid->inv_cellsize, x, density, velocity, velocity_smooth, density_gradient, velocity_gradient);
+  hair_grid_interpolate(grid->verts,
+                        grid->res,
+                        grid->gmin,
+                        grid->inv_cellsize,
+                        x,
+                        density,
+                        velocity,
+                        velocity_smooth,
+                        density_gradient,
+                        velocity_gradient);
 }
 
 void BPH_hair_volume_grid_velocity(
-        HairGrid *grid, const float x[3], const float v[3],
-        float fluid_factor,
-        float r_v[3])
+    HairGrid *grid, const float x[3], const float v[3], float fluid_factor, float r_v[3])
 {
-	float gdensity, gvelocity[3], gvel_smooth[3], ggrad[3], gvelgrad[3][3];
-	float v_pic[3], v_flip[3];
-
-	hair_grid_interpolate(grid->verts, grid->res, grid->gmin, grid->inv_cellsize, x, &gdensity, gvelocity, gvel_smooth, ggrad, gvelgrad);
-
-	/* velocity according to PIC method (Particle-in-Cell) */
-	copy_v3_v3(v_pic, gvel_smooth);
-
-	/* velocity according to FLIP method (Fluid-Implicit-Particle) */
-	sub_v3_v3v3(v_flip, gvel_smooth, gvelocity);
-	add_v3_v3(v_flip, v);
-
-	interp_v3_v3v3(r_v, v_pic, v_flip, fluid_factor);
+  float gdensity, gvelocity[3], gvel_smooth[3], ggrad[3], gvelgrad[3][3];
+  float v_pic[3], v_flip[3];
+
+  hair_grid_interpolate(grid->verts,
+                        grid->res,
+                        grid->gmin,
+                        grid->inv_cellsize,
+                        x,
+                        &gdensity,
+                        gvelocity,
+                        gvel_smooth,
+                        ggrad,
+                        gvelgrad);
+
+  /* velocity according to PIC method (Particle-in-Cell) */
+  copy_v3_v3(v_pic, gvel_smooth);
+
+  /* velocity according to FLIP method (Fluid-Implicit-Particle) */
+  sub_v3_v3v3(v_flip, gvel_smooth, gvelocity);
+  add_v3_v3(v_flip, v);
+
+  interp_v3_v3v3(r_v, v_pic, v_flip, fluid_factor);
 }
 
 void BPH_hair_volume_grid_clear(HairGrid *grid)
 {
-	const int size = hair_grid_size(grid->res);
-	int i;
-	for (i = 0; i < size; ++i) {
-		zero_v3(grid->verts[i].velocity);
-		zero_v3(grid->verts[i].velocity_smooth);
-		grid->verts[i].density = 0.0f;
-		grid->verts[i].samples = 0;
-	}
+  const int size = hair_grid_size(grid->res);
+  int i;
+  for (i = 0; i < size; ++i) {
+    zero_v3(grid->verts[i].velocity);
+    zero_v3(grid->verts[i].velocity_smooth);
+    grid->verts[i].density = 0.0f;
+    grid->verts[i].samples = 0;
+  }
 }
 
 BLI_INLINE bool hair_grid_point_valid(const float vec[3], float gmin[3], float gmax[3])
 {
-	return !(vec[0] < gmin[0] || vec[1] < gmin[1] || vec[2] < gmin[2] ||
-	         vec[0] > gmax[0] || vec[1] > gmax[1] || vec[2] > gmax[2]);
+  return !(vec[0] < gmin[0] || vec[1] < gmin[1] || vec[2] < gmin[2] || vec[0] > gmax[0] ||
+           vec[1] > gmax[1] || vec[2] > gmax[2]);
 }
 
 BLI_INLINE float dist_tent_v3f3(const float a[3], float x, float y, float z)
 {
-	float w = (1.0f - fabsf(a[0] - x)) * (1.0f - fabsf(a[1] - y)) * (1.0f - fabsf(a[2] - z));
-	return w;
+  float w = (1.0f - fabsf(a[0] - x)) * (1.0f - fabsf(a[1] - y)) * (1.0f - fabsf(a[2] - z));
+  return w;
 }
 
 BLI_INLINE float weights_sum(const float weights[8])
 {
-	float totweight = 0.0f;
-	int i;
-	for (i = 0; i < 8; ++i)
-		totweight += weights[i];
-	return totweight;
+  float totweight = 0.0f;
+  int i;
+  for (i = 0; i < 8; ++i)
+    totweight += weights[i];
+  return totweight;
 }
 
 /* returns the grid array offset as well to avoid redundant calculation */
-BLI_INLINE int hair_grid_weights(const int res[3], const float gmin[3], float scale, const float vec[3], float weights[8])
+BLI_INLINE int hair_grid_weights(
+    const int res[3], const float gmin[3], float scale, const float vec[3], float weights[8])
 {
-	int i, j, k, offset;
-	float uvw[3];
-
-	i = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 0);
-	j = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 1);
-	k = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 2);
-	offset = i + (j + k * res[1]) * res[0];
-
-	uvw[0] = (vec[0] - gmin[0]) * scale;
-	uvw[1] = (vec[1] - gmin[1]) * scale;
-	uvw[2] = (vec[2] - gmin[2]) * scale;
-
-	weights[0] = dist_tent_v3f3(uvw, (float)i      , (float)j      , (float)k      );
-	weights[1] = dist_tent_v3f3(uvw, (float)(i + 1), (float)j      , (float)k      );
-	weights[2] = dist_tent_v3f3(uvw, (float)i      , (float)(j + 1), (float)k      );
-	weights[3] = dist_tent_v3f3(uvw, (float)(i + 1), (float)(j + 1), (float)k      );
-	weights[4] = dist_tent_v3f3(uvw, (float)i      , (float)j      , (float)(k + 1));
-	weights[5] = dist_tent_v3f3(uvw, (float)(i + 1), (float)j      , (float)(k + 1));
-	weights[6] = dist_tent_v3f3(uvw, (float)i      , (float)(j + 1), (float)(k + 1));
-	weights[7] = dist_tent_v3f3(uvw, (float)(i + 1), (float)(j + 1), (float)(k + 1));
-
-//	BLI_assert(fabsf(weights_sum(weights) - 1.0f) < 0.0001f);
-
-	return offset;
+  int i, j, k, offset;
+  float uvw[3];
+
+  i = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 0);
+  j = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 1);
+  k = HAIR_GRID_INDEX_AXIS(vec, res, gmin, scale, 2);
+  offset = i + (j + k * res[1]) * res[0];
+
+  uvw[0] = (vec[0] - gmin[0]) * scale;
+  uvw[1] = (vec[1] - gmin[1]) * scale;
+  uvw[2] = (vec[2] - gmin[2]) * scale;
+
+  weights[0] = dist_tent_v3f3(uvw, (float)i, (float)j, (float)k);
+  weights[1] = dist_tent_v3f3(uvw, (float)(i + 1), (float)j, (float)k);
+  weights[2] = dist_tent_v3f3(uvw, (float)i, (float)(j + 1), (float)k);
+  weights[3] = dist_tent_v3f3(uvw, (float)(i + 1), (float)(j + 1), (float)k);
+  weights[4] = dist_tent_v3f3(uvw, (float)i, (float)j, (float)(k + 1));
+  weights[5] = dist_tent_v3f3(uvw, (float)(i + 1), (float)j, (float)(k + 1));
+  weights[6] = dist_tent_v3f3(uvw, (float)i, (float)(j + 1), (float)(k + 1));
+  weights[7] = dist_tent_v3f3(uvw, (float)(i + 1), (float)(j + 1), (float)(k + 1));
+
+  //  BLI_assert(fabsf(weights_sum(weights) - 1.0f) < 0.0001f);
+
+  return offset;
 }
 
 BLI_INLINE void grid_to_world(HairGrid *grid, float vecw[3], const float vec[3])
 {
-	copy_v3_v3(vecw, vec);
-	mul_v3_fl(vecw, grid->cellsize);
-	add_v3_v3(vecw, grid->gmin);
+  copy_v3_v3(vecw, vec);
+  mul_v3_fl(vecw, grid->cellsize);
+  add_v3_v3(vecw, grid->gmin);
 }
 
 void BPH_hair_volume_add_vertex(HairGrid *grid, const float x[3], const float v[3])
 {
-	const int res[3] = { grid->res[0], grid->res[1], grid->res[2] };
-	float weights[8];
-	int di, dj, dk;
-	int offset;
-
-	if (!hair_grid_point_valid(x, grid->gmin, grid->gmax))
-		return;
-
-	offset = hair_grid_weights(res, grid->gmin, grid->inv_cellsize, x, weights);
-
-	for (di = 0; di < 2; ++di) {
-		for (dj = 0; dj < 2; ++dj) {
-			for (dk = 0; dk < 2; ++dk) {
-				int voffset = offset + di + (dj + dk * res[1]) * res[0];
-				int iw = di + dj * 2 + dk * 4;
-
-				grid->verts[voffset].density += weights[iw];
-				madd_v3_v3fl(grid->verts[voffset].velocity, v, weights[iw]);
-			}
-		}
-	}
+  const int res[3] = {grid->res[0], grid->res[1], grid->res[2]};
+  float weights[8];
+  int di, dj, dk;
+  int offset;
+
+  if (!hair_grid_point_valid(x, grid->gmin, grid->gmax))
+    return;
+
+  offset = hair_grid_weights(res, grid->gmin, grid->inv_cellsize, x, weights);
+
+  for (di = 0; di < 2; ++di) {
+    for (dj = 0; dj < 2; ++dj) {
+      for (dk = 0; dk < 2; ++dk) {
+        int voffset = offset + di + (dj + dk * res[1]) * res[0];
+        int iw = di + dj * 2 + dk * 4;
+
+        grid->verts[voffset].density += weights[iw];
+        madd_v3_v3fl(grid->verts[voffset].velocity, v, weights[iw]);
+      }
+    }
+  }
 }
 
 #if 0
@@ -340,29 +393,29 @@ BLI_INLINE void hair_volume_eval_grid_vertex(
         HairGridVert *vert, const float loc[3], float radius, float dist_scale,
         const float x2[3], const float v2[3], const float x3[3], const float v3[3])
 {
-	float closest[3], lambda, dist, weight;
+  float closest[3], lambda, dist, weight;
 
-	lambda = closest_to_line_v3(closest, loc, x2, x3);
-	dist = len_v3v3(closest, loc);
+  lambda = closest_to_line_v3(closest, loc, x2, x3);
+  dist = len_v3v3(closest, loc);
 
-	weight = (radius - dist) * dist_scale;
+  weight = (radius - dist) * dist_scale;
 
-	if (weight > 0.0f) {
-		float vel[3];
+  if (weight > 0.0f) {
+    float vel[3];
 
-		interp_v3_v3v3(vel, v2, v3, lambda);
-		madd_v3_v3fl(vert->velocity, vel, weight);
-		vert->density += weight;
-		vert->samples += 1;
-	}
+    interp_v3_v3v3(vel, v2, v3, lambda);
+    madd_v3_v3fl(vert->velocity, vel, weight);
+    vert->density += weight;
+    vert->samples += 1;
+  }
 }
 
 BLI_INLINE int major_axis_v3(const float v[3])
 {
-	const float a = fabsf(v[0]);
-	const float b = fabsf(v[1]);
-	const float c = fabsf(v[2]);
-	return a > b ? (a > c ? 0 : 2) : (b > c ? 1 : 2);
+  const float a = fabsf(v[0]);
+  const float b = fabsf(v[1]);
+  const float c = fabsf(v[2]);
+  return a > b ? (a > c ? 0 : 2) : (b > c ? 1 : 2);
 }
 
 BLI_INLINE void hair_volume_add_segment_2D(
@@ -374,50 +427,50 @@ BLI_INLINE void hair_volume_add_segment_2D(
         HairGridVert *vert, int stride_j, int stride_k, const float loc[3], int axis_j, int axis_k,
         int debug_i)
 {
-	const float radius = 1.5f;
-	const float dist_scale = grid->inv_cellsize;
-
-	int j, k;
-
-	/* boundary checks to be safe */
-	CLAMP_MIN(jmin, 0);
-	CLAMP_MAX(jmax, resj - 1);
-	CLAMP_MIN(kmin, 0);
-	CLAMP_MAX(kmax, resk - 1);
-
-	HairGridVert *vert_j = vert + jmin * stride_j;
-	float loc_j[3] = { loc[0], loc[1], loc[2] };
-	loc_j[axis_j] += (float)jmin;
-	for (j = jmin; j <= jmax; ++j, vert_j += stride_j, loc_j[axis_j] += 1.0f) {
-
-		HairGridVert *vert_k = vert_j + kmin * stride_k;
-		float loc_k[3] = { loc_j[0], loc_j[1], loc_j[2] };
-		loc_k[axis_k] += (float)kmin;
-		for (k = kmin; k <= kmax; ++k, vert_k += stride_k, loc_k[axis_k] += 1.0f) {
-
-			hair_volume_eval_grid_vertex(vert_k, loc_k, radius, dist_scale, x2, v2, x3, v3);
-
-#if 0
-			{
-				float wloc[3], x2w[3], x3w[3];
-				grid_to_world(grid, wloc, loc_k);
-				grid_to_world(grid, x2w, x2);
-				grid_to_world(grid, x3w, x3);
-
-				if (vert_k->samples > 0)
-					BKE_sim_debug_data_add_circle(wloc, 0.01f, 1.0, 1.0, 0.3, "grid", 2525, debug_i, j, k);
-
-				if (grid->debug_value) {
-					BKE_sim_debug_data_add_dot(wloc, 1, 0, 0, "grid", 93, debug_i, j, k);
-					BKE_sim_debug_data_add_dot(x2w, 0.1, 0.1, 0.7, "grid", 649, debug_i, j, k);
-					BKE_sim_debug_data_add_line(wloc, x2w, 0.3, 0.8, 0.3, "grid", 253, debug_i, j, k);
-					BKE_sim_debug_data_add_line(wloc, x3w, 0.8, 0.3, 0.3, "grid", 254, debug_i, j, k);
-//					BKE_sim_debug_data_add_circle(x2w, len_v3v3(wloc, x2w), 0.2, 0.7, 0.2, "grid", 255, i, j, k);
-				}
-			}
-#endif
-		}
-	}
+  const float radius = 1.5f;
+  const float dist_scale = grid->inv_cellsize;
+
+  int j, k;
+
+  /* boundary checks to be safe */
+  CLAMP_MIN(jmin, 0);
+  CLAMP_MAX(jmax, resj - 1);
+  CLAMP_MIN(kmin, 0);
+  CLAMP_MAX(kmax, resk - 1);
+
+  HairGridVert *vert_j = vert + jmin * stride_j;
+  float loc_j[3] = { loc[0], loc[1], loc[2] };
+  loc_j[axis_j] += (float)jmin;
+  for (j = jmin; j <= jmax; ++j, vert_j += stride_j, loc_j[axis_j] += 1.0f) {
+
+    HairGridVert *vert_k = vert_j + kmin * stride_k;
+    float loc_k[3] = { loc_j[0], loc_j[1], loc_j[2] };
+    loc_k[axis_k] += (float)kmin;
+    for (k = kmin; k <= kmax; ++k, vert_k += stride_k, loc_k[axis_k] += 1.0f) {
+
+      hair_volume_eval_grid_vertex(vert_k, loc_k, radius, dist_scale, x2, v2, x3, v3);
+
+#  if 0
+      {
+        float wloc[3], x2w[3], x3w[3];
+        grid_to_world(grid, wloc, loc_k);
+        grid_to_world(grid, x2w, x2);
+        grid_to_world(grid, x3w, x3);
+
+        if (vert_k->samples > 0)
+          BKE_sim_debug_data_add_circle(wloc, 0.01f, 1.0, 1.0, 0.3, "grid", 2525, debug_i, j, k);
+
+        if (grid->debug_value) {
+          BKE_sim_debug_data_add_dot(wloc, 1, 0, 0, "grid", 93, debug_i, j, k);
+          BKE_sim_debug_data_add_dot(x2w, 0.1, 0.1, 0.7, "grid", 649, debug_i, j, k);
+          BKE_sim_debug_data_add_line(wloc, x2w, 0.3, 0.8, 0.3, "grid", 253, debug_i, j, k);
+          BKE_sim_debug_data_add_line(wloc, x3w, 0.8, 0.3, 0.3, "grid", 254, debug_i, j, k);
+//                  BKE_sim_debug_data_add_circle(x2w, len_v3v3(wloc, x2w), 0.2, 0.7, 0.2, "grid", 255, i, j, k);
+        }
+      }
+#  endif
+    }
+  }
 }
 
 /* Uses a variation of Bresenham's algorithm for rasterizing a 3D grid with a line segment.
@@ -431,191 +484,207 @@ void BPH_hair_volume_add_segment(
         const float x3[3], const float v3[3], const float x4[3], const float v4[3],
         const float dir1[3], const float dir2[3], const float dir3[3])
 {
-	const int res[3] = { grid->res[0], grid->res[1], grid->res[2] };
-
-	/* find the primary direction from the major axis of the direction vector */
-	const int axis0 = major_axis_v3(dir2);
-	const int axis1 = (axis0 + 1) % 3;
-	const int axis2 = (axis0 + 2) % 3;
-
-	/* vertex buffer offset factors along cardinal axes */
-	const int strides[3] = { 1, res[0], res[0] * res[1] };
-	const int stride0 = strides[axis0];
-	const int stride1 = strides[axis1];
-	const int stride2 = strides[axis2];
-
-	/* increment of secondary directions per step in the primary direction
-	 * note: we always go in the positive direction along axis0, so the sign can be inverted
-	 */
-	const float inc1 = dir2[axis1] / dir2[axis0];
-	const float inc2 = dir2[axis2] / dir2[axis0];
-
-	/* start/end points, so increment along axis0 is always positive */
-	const float *start = x2[axis0] < x3[axis0] ? x2 : x3;
-	const float *end   = x2[axis0] < x3[axis0] ? x3 : x2;
-	const float start0 = start[axis0], start1 = start[axis1], start2 = start[axis2];
-	const float end0 = end[axis0];
-
-	/* range along primary direction */
-	const int imin = max_ii(floor_int(start[axis0]) - 1, 0);
-	const int imax = min_ii(floor_int(end[axis0]) + 2, res[axis0] - 1);
-
-	float h = 0.0f;
-	HairGridVert *vert0;
-	float loc0[3];
-	int j0, k0, j0_prev, k0_prev;
-	int i;
-
-	for (i = imin; i <= imax; ++i) {
-		float shift1, shift2; /* fraction of a full cell shift [0.0, 1.0) */
-		int jmin, jmax, kmin, kmax;
-
-		h = CLAMPIS((float)i, start0, end0);
-
-		shift1 = start1 + (h - start0) * inc1;
-		shift2 = start2 + (h - start0) * inc2;
-
-		j0_prev = j0;
-		j0 = floor_int(shift1);
-
-		k0_prev = k0;
-		k0 = floor_int(shift2);
-
-		if (i > imin) {
-			jmin = min_ii(j0, j0_prev);
-			jmax = max_ii(j0, j0_prev);
-			kmin = min_ii(k0, k0_prev);
-			kmax = max_ii(k0, k0_prev);
-		}
-		else {
-			jmin = jmax = j0;
-			kmin = kmax = k0;
-		}
-
-		vert0 = grid->verts + i * stride0;
-		loc0[axis0] = (float)i;
-		loc0[axis1] = 0.0f;
-		loc0[axis2] = 0.0f;
-
-		hair_volume_add_segment_2D(
-		        grid, x1, v1, x2, v2, x3, v3, x4, v4, dir1, dir2, dir3,
-		        res[axis1], res[axis2], jmin - 1, jmax + 2, kmin - 1, kmax + 2,
-		        vert0, stride1, stride2, loc0, axis1, axis2,
-		        i);
-	}
+  const int res[3] = { grid->res[0], grid->res[1], grid->res[2] };
+
+  /* find the primary direction from the major axis of the direction vector */
+  const int axis0 = major_axis_v3(dir2);
+  const int axis1 = (axis0 + 1) % 3;
+  const int axis2 = (axis0 + 2) % 3;
+
+  /* vertex buffer offset factors along cardinal axes */
+  const int strides[3] = { 1, res[0], res[0] * res[1] };
+  const int stride0 = strides[axis0];
+  const int stride1 = strides[axis1];
+  const int stride2 = strides[axis2];
+
+  /* increment of secondary directions per step in the primary direction
+   * note: we always go in the positive direction along axis0, so the sign can be inverted
+   */
+  const float inc1 = dir2[axis1] / dir2[axis0];
+  const float inc2 = dir2[axis2] / dir2[axis0];
+
+  /* start/end points, so increment along axis0 is always positive */
+  const float *start = x2[axis0] < x3[axis0] ? x2 : x3;
+  const float *end   = x2[axis0] < x3[axis0] ? x3 : x2;
+  const float start0 = start[axis0], start1 = start[axis1], start2 = start[axis2];
+  const float end0 = end[axis0];
+
+  /* range along primary direction */
+  const int imin = max_ii(floor_int(start[axis0]) - 1, 0);
+  const int imax = min_ii(floor_int(end[axis0]) + 2, res[axis0] - 1);
+
+  float h = 0.0f;
+  HairGridVert *vert0;
+  float loc0[3];
+  int j0, k0, j0_prev, k0_prev;
+  int i;
+
+  for (i = imin; i <= imax; ++i) {
+    float shift1, shift2; /* fraction of a full cell shift [0.0, 1.0) */
+    int jmin, jmax, kmin, kmax;
+
+    h = CLAMPIS((float)i, start0, end0);
+
+    shift1 = start1 + (h - start0) * inc1;
+    shift2 = start2 + (h - start0) * inc2;
+
+    j0_prev = j0;
+    j0 = floor_int(shift1);
+
+    k0_prev = k0;
+    k0 = floor_int(shift2);
+
+    if (i > imin) {
+      jmin = min_ii(j0, j0_prev);
+      jmax = max_ii(j0, j0_prev);
+      kmin = min_ii(k0, k0_prev);
+      kmax = max_ii(k0, k0_prev);
+    }
+    else {
+      jmin = jmax = j0;
+      kmin = kmax = k0;
+    }
+
+    vert0 = grid->verts + i * stride0;
+    loc0[axis0] = (float)i;
+    loc0[axis1] = 0.0f;
+    loc0[axis2] = 0.0f;
+
+    hair_volume_add_segment_2D(
+            grid, x1, v1, x2, v2, x3, v3, x4, v4, dir1, dir2, dir3,
+            res[axis1], res[axis2], jmin - 1, jmax + 2, kmin - 1, kmax + 2,
+            vert0, stride1, stride2, loc0, axis1, axis2,
+            i);
+  }
 }
 #else
-BLI_INLINE void hair_volume_eval_grid_vertex_sample(
-        HairGridVert *vert, const float loc[3], float radius, float dist_scale,
-        const float x[3], const float v[3])
+BLI_INLINE void hair_volume_eval_grid_vertex_sample(HairGridVert *vert,
+                                                    const float loc[3],
+                                                    float radius,
+                                                    float dist_scale,
+                                                    const float x[3],
+                                                    const float v[3])
 {
-	float dist, weight;
+  float dist, weight;
 
-	dist = len_v3v3(x, loc);
+  dist = len_v3v3(x, loc);
 
-	weight = (radius - dist) * dist_scale;
+  weight = (radius - dist) * dist_scale;
 
-	if (weight > 0.0f) {
-		madd_v3_v3fl(vert->velocity, v, weight);
-		vert->density += weight;
-		vert->samples += 1;
-	}
+  if (weight > 0.0f) {
+    madd_v3_v3fl(vert->velocity, v, weight);
+    vert->density += weight;
+    vert->samples += 1;
+  }
 }
 
 /* XXX simplified test implementation using a series of discrete sample along the segment,
  * instead of finding the closest point for all affected grid vertices.
  */
-void BPH_hair_volume_add_segment(
-        HairGrid *grid,
-        const float UNUSED(x1[3]), const float UNUSED(v1[3]), const float x2[3], const float v2[3],
-        const float x3[3], const float v3[3], const float UNUSED(x4[3]), const float UNUSED(v4[3]),
-        const float UNUSED(dir1[3]), const float UNUSED(dir2[3]), const float UNUSED(dir3[3]))
+void BPH_hair_volume_add_segment(HairGrid *grid,
+                                 const float UNUSED(x1[3]),
+                                 const float UNUSED(v1[3]),
+                                 const float x2[3],
+                                 const float v2[3],
+                                 const float x3[3],
+                                 const float v3[3],
+                                 const float UNUSED(x4[3]),
+                                 const float UNUSED(v4[3]),
+                                 const float UNUSED(dir1[3]),
+                                 const float UNUSED(dir2[3]),
+                                 const float UNUSED(dir3[3]))
 {
-	const float radius = 1.5f;
-	const float dist_scale = grid->inv_cellsize;
-
-	const int res[3] = { grid->res[0], grid->res[1], grid->res[2] };
-	const int stride[3] = { 1, res[0], res[0] * res[1] };
-	const int num_samples = 10;
-
-	int s;
-
-	for (s = 0; s < num_samples; ++s) {
-		float x[3], v[3];
-		int i, j, k;
-
-		float f = (float)s / (float)(num_samples - 1);
-		interp_v3_v3v3(x, x2, x3, f);
-		interp_v3_v3v3(v, v2, v3, f);
-
-		int imin = max_ii(floor_int(x[0]) - 2, 0);
-		int imax = min_ii(floor_int(x[0]) + 2, res[0] - 1);
-		int jmin = max_ii(floor_int(x[1]) - 2, 0);
-		int jmax = min_ii(floor_int(x[1]) + 2, res[1] - 1);
-		int kmin = max_ii(floor_int(x[2]) - 2, 0);
-		int kmax = min_ii(floor_int(x[2]) + 2, res[2] - 1);
-
-		for (k = kmin; k <= kmax; ++k) {
-			for (j = jmin; j <= jmax; ++j) {
-				for (i = imin; i <= imax; ++i) {
-					float loc[3] = { (float)i, (float)j, (float)k };
-					HairGridVert *vert = grid->verts + i * stride[0] + j * stride[1] + k * stride[2];
-
-					hair_volume_eval_grid_vertex_sample(vert, loc, radius, dist_scale, x, v);
-				}
-			}
-		}
-	}
+  const float radius = 1.5f;
+  const float dist_scale = grid->inv_cellsize;
+
+  const int res[3] = {grid->res[0], grid->res[1], grid->res[2]};
+  const int stride[3] = {1, res[0], res[0] * res[1]};
+  const int num_samples = 10;
+
+  int s;
+
+  for (s = 0; s < num_samples; ++s) {
+    float x[3], v[3];
+    int i, j, k;
+
+    float f = (float)s / (float)(num_samples - 1);
+    interp_v3_v3v3(x, x2, x3, f);
+    interp_v3_v3v3(v, v2, v3, f);
+
+    int imin = max_ii(floor_int(x[0]) - 2, 0);
+    int imax = min_ii(floor_int(x[0]) + 2, res[0] - 1);
+    int jmin = max_ii(floor_int(x[1]) - 2, 0);
+    int jmax = min_ii(floor_int(x[1]) + 2, res[1] - 1);
+    int kmin = max_ii(floor_int(x[2]) - 2, 0);
+    int kmax = min_ii(floor_int(x[2]) + 2, res[2] - 1);
+
+    for (k = kmin; k <= kmax; ++k) {
+      for (j = jmin; j <= jmax; ++j) {
+        for (i = imin; i <= imax; ++i) {
+          float loc[3] = {(float)i, (float)j, (float)k};
+          HairGridVert *vert = grid->verts + i * stride[0] + j * stride[1] + k * stride[2];
+
+          hair_volume_eval_grid_vertex_sample(vert, loc, radius, dist_scale, x, v);
+        }
+      }
+    }
+  }
 }
 #endif
 
 void BPH_hair_volume_normalize_vertex_grid(HairGrid *grid)
 {
-	int i, size = hair_grid_size(grid->res);
-	/* divide velocity with density */
-	for (i = 0; i < size; i++) {
-		float density = grid->verts[i].density;
-		if (density > 0.0f)
-			mul_v3_fl(grid->verts[i].velocity, 1.0f / density);
-	}
+  int i, size = hair_grid_size(grid->res);
+  /* divide velocity with density */
+  for (i = 0; i < size; i++) {
+    float density = grid->verts[i].density;
+    if (density > 0.0f)
+      mul_v3_fl(grid->verts[i].velocity, 1.0f / density);
+  }
 }
 
-static const float density_threshold = 0.001f; /* cells with density below this are considered empty */
+static const float density_threshold =
+    0.001f; /* cells with density below this are considered empty */
 
 /* Contribution of target density pressure to the laplacian in the pressure poisson equation.
  * This is based on the model found in
  * "Two-way Coupled SPH and Particle Level Set Fluid Simulation" (Losasso et al., 2008)
  */
-BLI_INLINE float hair_volume_density_divergence(float density, float target_density, float strength)
+BLI_INLINE float hair_volume_density_divergence(float density,
+                                                float target_density,
+                                                float strength)
 {
-	if (density > density_threshold && density > target_density)
-		return strength * logf(target_density / density);
-	else
-		return 0.0f;
+  if (density > density_threshold && density > target_density)
+    return strength * logf(target_density / density);
+  else
+    return 0.0f;
 }
 
-bool BPH_hair_volume_solve_divergence(HairGrid *grid, float /*dt*/, float target_density, float target_strength)
+bool BPH_hair_volume_solve_divergence(HairGrid *grid,
+                                      float /*dt*/,
+                                      float target_density,
+                                      float target_strength)
 {
-	const float flowfac = grid->cellsize;
-	const float inv_flowfac = 1.0f / grid->cellsize;
+  const float flowfac = grid->cellsize;
+  const float inv_flowfac = 1.0f / grid->cellsize;
 
-	/*const int num_cells = hair_grid_size(grid->res);*/
-	const int res[3] = { grid->res[0], grid->res[1], grid->res[2] };
-	const int resA[3] = { grid->res[0] + 2, grid->res[1] + 2, grid->res[2] + 2 };
+  /*const int num_cells = hair_grid_size(grid->res);*/
+  const int res[3] = {grid->res[0], grid->res[1], grid->res[2]};
+  const int resA[3] = {grid->res[0] + 2, grid->res[1] + 2, grid->res[2] + 2};
 
-	const int stride0 = 1;
-	const int stride1 = grid->res[0];
-	const int stride2 = grid->res[1] * grid->res[0];
-	const int strideA0 = 1;
-	const int strideA1 = grid->res[0] + 2;
-	const int strideA2 = (grid->res[1] + 2) * (grid->res[0] + 2);
+  const int stride0 = 1;
+  const int stride1 = grid->res[0];
+  const int stride2 = grid->res[1] * grid->res[0];
+  const int strideA0 = 1;
+  const int strideA1 = grid->res[0] + 2;
+  const int strideA2 = (grid->res[1] + 2) * (grid->res[0] + 2);
 
-	const int num_cells = res[0] * res[1] * res[2];
-	const int num_cellsA = (res[0] + 2) * (res[1] + 2) * (res[2] + 2);
+  const int num_cells = res[0] * res[1] * res[2];
+  const int num_cellsA = (res[0] + 2) * (res[1] + 2) * (res[2] + 2);
 
-	HairGridVert *vert_start = grid->verts - (stride0 + stride1 + stride2);
-	HairGridVert *vert;
-	int i, j, k;
+  HairGridVert *vert_start = grid->verts - (stride0 + stride1 + stride2);
+  HairGridVert *vert;
+  int i, j, k;
 
 #define MARGIN_i0 (i < 1)
 #define MARGIN_j0 (j < 1)
@@ -631,259 +700,263 @@ bool BPH_hair_volume_solve_divergence(HairGrid *grid, float /*dt*/, float target
 #define NEIGHBOR_MARGIN_j1 (j >= resA[1] - 2)
 #define NEIGHBOR_MARGIN_k1 (k >= resA[2] - 2)
 
-	BLI_assert(num_cells >= 1);
-
-	/* Calculate divergence */
-	lVector B(num_cellsA);
-	for (k = 0; k < resA[2]; ++k) {
-		for (j = 0; j < resA[1]; ++j) {
-			for (i = 0; i < resA[0]; ++i) {
-				int u = i * strideA0 + j * strideA1 + k * strideA2;
-				bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 || MARGIN_k1;
-
-				if (is_margin) {
-					B[u] = 0.0f;
-					continue;
-				}
-
-				vert = vert_start + i * stride0 + j * stride1 + k * stride2;
-
-				const float *v0 = vert->velocity;
-				float dx = 0.0f, dy = 0.0f, dz = 0.0f;
-				if (!NEIGHBOR_MARGIN_i0)
-					dx += v0[0] - (vert - stride0)->velocity[0];
-				if (!NEIGHBOR_MARGIN_i1)
-					dx += (vert + stride0)->velocity[0] - v0[0];
-				if (!NEIGHBOR_MARGIN_j0)
-					dy += v0[1] - (vert - stride1)->velocity[1];
-				if (!NEIGHBOR_MARGIN_j1)
-					dy += (vert + stride1)->velocity[1] - v0[1];
-				if (!NEIGHBOR_MARGIN_k0)
-					dz += v0[2] - (vert - stride2)->velocity[2];
-				if (!NEIGHBOR_MARGIN_k1)
-					dz += (vert + stride2)->velocity[2] - v0[2];
-
-				float divergence = -0.5f * flowfac * (dx + dy + dz);
-
-				/* adjustment term for target density */
-				float target = hair_volume_density_divergence(vert->density, target_density, target_strength);
-
-				/* B vector contains the finite difference approximation of the velocity divergence.
-				 * Note: according to the discretized Navier-Stokes equation the rhs vector
-				 * and resulting pressure gradient should be multiplied by the (inverse) density;
-				 * however, this is already included in the weighting of hair velocities on the grid!
-				 */
-				B[u] = divergence - target;
+  BLI_assert(num_cells >= 1);
+
+  /* Calculate divergence */
+  lVector B(num_cellsA);
+  for (k = 0; k < resA[2]; ++k) {
+    for (j = 0; j < resA[1]; ++j) {
+      for (i = 0; i < resA[0]; ++i) {
+        int u = i * strideA0 + j * strideA1 + k * strideA2;
+        bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 ||
+                         MARGIN_k1;
+
+        if (is_margin) {
+          B[u] = 0.0f;
+          continue;
+        }
+
+        vert = vert_start + i * stride0 + j * stride1 + k * stride2;
+
+        const float *v0 = vert->velocity;
+        float dx = 0.0f, dy = 0.0f, dz = 0.0f;
+        if (!NEIGHBOR_MARGIN_i0)
+          dx += v0[0] - (vert - stride0)->velocity[0];
+        if (!NEIGHBOR_MARGIN_i1)
+          dx += (vert + stride0)->velocity[0] - v0[0];
+        if (!NEIGHBOR_MARGIN_j0)
+          dy += v0[1] - (vert - stride1)->velocity[1];
+        if (!NEIGHBOR_MARGIN_j1)
+          dy += (vert + stride1)->velocity[1] - v0[1];
+        if (!NEIGHBOR_MARGIN_k0)
+          dz += v0[2] - (vert - stride2)->velocity[2];
+        if (!NEIGHBOR_MARGIN_k1)
+          dz += (vert + stride2)->velocity[2] - v0[2];
+
+        float divergence = -0.5f * flowfac * (dx + dy + dz);
+
+        /* adjustment term for target density */
+        float target = hair_volume_density_divergence(
+            vert->density, target_density, target_strength);
+
+        /* B vector contains the finite difference approximation of the velocity divergence.
+         * Note: according to the discretized Navier-Stokes equation the rhs vector
+         * and resulting pressure gradient should be multiplied by the (inverse) density;
+         * however, this is already included in the weighting of hair velocities on the grid!
+         */
+        B[u] = divergence - target;
 
 #if 0
-				{
-					float wloc[3], loc[3];
-					float col0[3] = {0.0, 0.0, 0.0};
-					float colp[3] = {0.0, 1.0, 1.0};
-					float coln[3] = {1.0, 0.0, 1.0};
-					float col[3];
-					float fac;
-
-					loc[0] = (float)(i - 1);
-					loc[1] = (float)(j - 1);
-					loc[2] = (float)(k - 1);
-					grid_to_world(grid, wloc, loc);
-
-					if (divergence > 0.0f) {
-						fac = CLAMPIS(divergence * target_strength, 0.0, 1.0);
-						interp_v3_v3v3(col, col0, colp, fac);
-					}
-					else {
-						fac = CLAMPIS(-divergence * target_strength, 0.0, 1.0);
-						interp_v3_v3v3(col, col0, coln, fac);
-					}
-					if (fac > 0.05f)
-						BKE_sim_debug_data_add_circle(grid->debug_data, wloc, 0.01f, col[0], col[1], col[2], "grid", 5522, i, j, k);
-				}
+        {
+          float wloc[3], loc[3];
+          float col0[3] = {0.0, 0.0, 0.0};
+          float colp[3] = {0.0, 1.0, 1.0};
+          float coln[3] = {1.0, 0.0, 1.0};
+          float col[3];
+          float fac;
+
+          loc[0] = (float)(i - 1);
+          loc[1] = (float)(j - 1);
+          loc[2] = (float)(k - 1);
+          grid_to_world(grid, wloc, loc);
+
+          if (divergence > 0.0f) {
+            fac = CLAMPIS(divergence * target_strength, 0.0, 1.0);
+            interp_v3_v3v3(col, col0, colp, fac);
+          }
+          else {
+            fac = CLAMPIS(-divergence * target_strength, 0.0, 1.0);
+            interp_v3_v3v3(col, col0, coln, fac);
+          }
+          if (fac > 0.05f)
+            BKE_sim_debug_data_add_circle(grid->debug_data, wloc, 0.01f, col[0], col[1], col[2], "grid", 5522, i, j, k);
+        }
 #endif
-			}
-		}
-	}
-
-	/* Main Poisson equation system:
-	 * This is derived from the discretezation of the Poisson equation
-	 *   div(grad(p)) = div(v)
-	 *
-	 * The finite difference approximation yields the linear equation system described here:
-	 * https://en.wikipedia.org/wiki/Discrete_Poisson_equation
-	 */
-	lMatrix A(num_cellsA, num_cellsA);
-	/* Reserve space for the base equation system (without boundary conditions).
-	 * Each column contains a factor 6 on the diagonal
-	 * and up to 6 factors -1 on other places.
-	 */
-	A.reserve(Eigen::VectorXi::Constant(num_cellsA, 7));
-
-	for (k = 0; k < resA[2]; ++k) {
-		for (j = 0; j < resA[1]; ++j) {
-			for (i = 0; i < resA[0]; ++i) {
-				int u = i * strideA0 + j * strideA1 + k * strideA2;
-				bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 || MARGIN_k1;
-
-				vert = vert_start + i * stride0 + j * stride1 + k * stride2;
-				if (!is_margin && vert->density > density_threshold) {
-					int neighbors_lo = 0;
-					int neighbors_hi = 0;
-					int non_solid_neighbors = 0;
-					int neighbor_lo_index[3];
-					int neighbor_hi_index[3];
-					int n;
-
-					/* check for upper bounds in advance
-					 * to get the correct number of neighbors,
-					 * needed for the diagonal element
-					 */
-					if (!NEIGHBOR_MARGIN_k0 && (vert - stride2)->density > density_threshold)
-						neighbor_lo_index[neighbors_lo++] = u - strideA2;
-					if (!NEIGHBOR_MARGIN_j0 && (vert - stride1)->density > density_threshold)
-						neighbor_lo_index[neighbors_lo++] = u - strideA1;
-					if (!NEIGHBOR_MARGIN_i0 && (vert - stride0)->density > density_threshold)
-						neighbor_lo_index[neighbors_lo++] = u - strideA0;
-					if (!NEIGHBOR_MARGIN_i1 && (vert + stride0)->density > density_threshold)
-						neighbor_hi_index[neighbors_hi++] = u + strideA0;
-					if (!NEIGHBOR_MARGIN_j1 && (vert + stride1)->density > density_threshold)
-						neighbor_hi_index[neighbors_hi++] = u + strideA1;
-					if (!NEIGHBOR_MARGIN_k1 && (vert + stride2)->density > density_threshold)
-						neighbor_hi_index[neighbors_hi++] = u + strideA2;
-
-					/*int liquid_neighbors = neighbors_lo + neighbors_hi;*/
-					non_solid_neighbors = 6;
-
-					for (n = 0; n < neighbors_lo; ++n)
-						A.insert(neighbor_lo_index[n], u) = -1.0f;
-					A.insert(u, u) = (float)non_solid_neighbors;
-					for (n = 0; n < neighbors_hi; ++n)
-						A.insert(neighbor_hi_index[n], u) = -1.0f;
-				}
-				else {
-					A.insert(u, u) = 1.0f;
-				}
-			}
-		}
-	}
-
-	ConjugateGradient cg;
-	cg.setMaxIterations(100);
-	cg.setTolerance(0.01f);
-
-	cg.compute(A);
-
-	lVector p = cg.solve(B);
-
-	if (cg.info() == Eigen::Success) {
-		/* Calculate velocity = grad(p) */
-		for (k = 0; k < resA[2]; ++k) {
-			for (j = 0; j < resA[1]; ++j) {
-				for (i = 0; i < resA[0]; ++i) {
-					int u = i * strideA0 + j * strideA1 + k * strideA2;
-					bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 || MARGIN_k1;
-					if (is_margin)
-						continue;
-
-					vert = vert_start + i * stride0 + j * stride1 + k * stride2;
-					if (vert->density > density_threshold) {
-						float p_left   = p[u - strideA0];
-						float p_right  = p[u + strideA0];
-						float p_down   = p[u - strideA1];
-						float p_up     = p[u + strideA1];
-						float p_bottom = p[u - strideA2];
-						float p_top    = p[u + strideA2];
-
-						/* finite difference estimate of pressure gradient */
-						float dvel[3];
-						dvel[0] = p_right - p_left;
-						dvel[1] = p_up - p_down;
-						dvel[2] = p_top - p_bottom;
-						mul_v3_fl(dvel, -0.5f * inv_flowfac);
-
-						/* pressure gradient describes velocity delta */
-						add_v3_v3v3(vert->velocity_smooth, vert->velocity, dvel);
-					}
-					else {
-						zero_v3(vert->velocity_smooth);
-					}
-				}
-			}
-		}
+      }
+    }
+  }
+
+  /* Main Poisson equation system:
+   * This is derived from the discretezation of the Poisson equation
+   *   div(grad(p)) = div(v)
+   *
+   * The finite difference approximation yields the linear equation system described here:
+   * https://en.wikipedia.org/wiki/Discrete_Poisson_equation
+   */
+  lMatrix A(num_cellsA, num_cellsA);
+  /* Reserve space for the base equation system (without boundary conditions).
+   * Each column contains a factor 6 on the diagonal
+   * and up to 6 factors -1 on other places.
+   */
+  A.reserve(Eigen::VectorXi::Constant(num_cellsA, 7));
+
+  for (k = 0; k < resA[2]; ++k) {
+    for (j = 0; j < resA[1]; ++j) {
+      for (i = 0; i < resA[0]; ++i) {
+        int u = i * strideA0 + j * strideA1 + k * strideA2;
+        bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 ||
+                         MARGIN_k1;
+
+        vert = vert_start + i * stride0 + j * stride1 + k * stride2;
+        if (!is_margin && vert->density > density_threshold) {
+          int neighbors_lo = 0;
+          int neighbors_hi = 0;
+          int non_solid_neighbors = 0;
+          int neighbor_lo_index[3];
+          int neighbor_hi_index[3];
+          int n;
+
+          /* check for upper bounds in advance
+           * to get the correct number of neighbors,
+           * needed for the diagonal element
+           */
+          if (!NEIGHBOR_MARGIN_k0 && (vert - stride2)->density > density_threshold)
+            neighbor_lo_index[neighbors_lo++] = u - strideA2;
+          if (!NEIGHBOR_MARGIN_j0 && (vert - stride1)->density > density_threshold)
+            neighbor_lo_index[neighbors_lo++] = u - strideA1;
+          if (!NEIGHBOR_MARGIN_i0 && (vert - stride0)->density > density_threshold)
+            neighbor_lo_index[neighbors_lo++] = u - strideA0;
+          if (!NEIGHBOR_MARGIN_i1 && (vert + stride0)->density > density_threshold)
+            neighbor_hi_index[neighbors_hi++] = u + strideA0;
+          if (!NEIGHBOR_MARGIN_j1 && (vert + stride1)->density > density_threshold)
+            neighbor_hi_index[neighbors_hi++] = u + strideA1;
+          if (!NEIGHBOR_MARGIN_k1 && (vert + stride2)->density > density_threshold)
+            neighbor_hi_index[neighbors_hi++] = u + strideA2;
+
+          /*int liquid_neighbors = neighbors_lo + neighbors_hi;*/
+          non_solid_neighbors = 6;
+
+          for (n = 0; n < neighbors_lo; ++n)
+            A.insert(neighbor_lo_index[n], u) = -1.0f;
+          A.insert(u, u) = (float)non_solid_neighbors;
+          for (n = 0; n < neighbors_hi; ++n)
+            A.insert(neighbor_hi_index[n], u) = -1.0f;
+        }
+        else {
+          A.insert(u, u) = 1.0f;
+        }
+      }
+    }
+  }
+
+  ConjugateGradient cg;
+  cg.setMaxIterations(100);
+  cg.setTolerance(0.01f);
+
+  cg.compute(A);
+
+  lVector p = cg.solve(B);
+
+  if (cg.info() == Eigen::Success) {
+    /* Calculate velocity = grad(p) */
+    for (k = 0; k < resA[2]; ++k) {
+      for (j = 0; j < resA[1]; ++j) {
+        for (i = 0; i < resA[0]; ++i) {
+          int u = i * strideA0 + j * strideA1 + k * strideA2;
+          bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 ||
+                           MARGIN_k1;
+          if (is_margin)
+            continue;
+
+          vert = vert_start + i * stride0 + j * stride1 + k * stride2;
+          if (vert->density > density_threshold) {
+            float p_left = p[u - strideA0];
+            float p_right = p[u + strideA0];
+            float p_down = p[u - strideA1];
+            float p_up = p[u + strideA1];
+            float p_bottom = p[u - strideA2];
+            float p_top = p[u + strideA2];
+
+            /* finite difference estimate of pressure gradient */
+            float dvel[3];
+            dvel[0] = p_right - p_left;
+            dvel[1] = p_up - p_down;
+            dvel[2] = p_top - p_bottom;
+            mul_v3_fl(dvel, -0.5f * inv_flowfac);
+
+            /* pressure gradient describes velocity delta */
+            add_v3_v3v3(vert->velocity_smooth, vert->velocity, dvel);
+          }
+          else {
+            zero_v3(vert->velocity_smooth);
+          }
+        }
+      }
+    }
 
 #if 0
-		{
-			int axis = 0;
-			float offset = 0.0f;
-
-			int slice = (offset - grid->gmin[axis]) / grid->cellsize;
-
-			for (k = 0; k < resA[2]; ++k) {
-				for (j = 0; j < resA[1]; ++j) {
-					for (i = 0; i < resA[0]; ++i) {
-						int u = i * strideA0 + j * strideA1 + k * strideA2;
-						bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 || MARGIN_k1;
-						if (i != slice)
-							continue;
-
-						vert = vert_start + i * stride0 + j * stride1 + k * stride2;
-
-						float wloc[3], loc[3];
-						float col0[3] = {0.0, 0.0, 0.0};
-						float colp[3] = {0.0, 1.0, 1.0};
-						float coln[3] = {1.0, 0.0, 1.0};
-						float col[3];
-						float fac;
-
-						loc[0] = (float)(i - 1);
-						loc[1] = (float)(j - 1);
-						loc[2] = (float)(k - 1);
-						grid_to_world(grid, wloc, loc);
-
-						float pressure = p[u];
-						if (pressure > 0.0f) {
-							fac = CLAMPIS(pressure * grid->debug1, 0.0, 1.0);
-							interp_v3_v3v3(col, col0, colp, fac);
-						}
-						else {
-							fac = CLAMPIS(-pressure * grid->debug1, 0.0, 1.0);
-							interp_v3_v3v3(col, col0, coln, fac);
-						}
-						if (fac > 0.05f)
-							BKE_sim_debug_data_add_circle(grid->debug_data, wloc, 0.01f, col[0], col[1], col[2], "grid", 5533, i, j, k);
-
-						if (!is_margin) {
-							float dvel[3];
-							sub_v3_v3v3(dvel, vert->velocity_smooth, vert->velocity);
-//							BKE_sim_debug_data_add_vector(grid->debug_data, wloc, dvel, 1, 1, 1, "grid", 5566, i, j, k);
-						}
-
-						if (!is_margin) {
-							float d = CLAMPIS(vert->density * grid->debug2, 0.0f, 1.0f);
-							float col0[3] = {0.3, 0.3, 0.3};
-							float colp[3] = {0.0, 0.0, 1.0};
-							float col[3];
-
-							interp_v3_v3v3(col, col0, colp, d);
-//							if (d > 0.05f)
-//								BKE_sim_debug_data_add_dot(grid->debug_data, wloc, col[0], col[1], col[2], "grid", 5544, i, j, k);
-						}
-					}
-				}
-			}
-		}
+    {
+      int axis = 0;
+      float offset = 0.0f;
+
+      int slice = (offset - grid->gmin[axis]) / grid->cellsize;
+
+      for (k = 0; k < resA[2]; ++k) {
+        for (j = 0; j < resA[1]; ++j) {
+          for (i = 0; i < resA[0]; ++i) {
+            int u = i * strideA0 + j * strideA1 + k * strideA2;
+            bool is_margin = MARGIN_i0 || MARGIN_i1 || MARGIN_j0 || MARGIN_j1 || MARGIN_k0 || MARGIN_k1;
+            if (i != slice)
+              continue;
+
+            vert = vert_start + i * stride0 + j * stride1 + k * stride2;
+
+            float wloc[3], loc[3];
+            float col0[3] = {0.0, 0.0, 0.0};
+            float colp[3] = {0.0, 1.0, 1.0};
+            float coln[3] = {1.0, 0.0, 1.0};
+            float col[3];
+            float fac;
+
+            loc[0] = (float)(i - 1);
+            loc[1] = (float)(j - 1);
+            loc[2] = (float)(k - 1);
+            grid_to_world(grid, wloc, loc);
+
+            float pressure = p[u];
+            if (pressure > 0.0f) {
+              fac = CLAMPIS(pressure * grid->debug1, 0.0, 1.0);
+              interp_v3_v3v3(col, col0, colp, fac);
+            }
+            else {
+              fac = CLAMPIS(-pressure * grid->debug1, 0.0, 1.0);
+              interp_v3_v3v3(col, col0, coln, fac);
+            }
+            if (fac > 0.05f)
+              BKE_sim_debug_data_add_circle(grid->debug_data, wloc, 0.01f, col[0], col[1], col[2], "grid", 5533, i, j, k);
+
+            if (!is_margin) {
+              float dvel[3];
+              sub_v3_v3v3(dvel, vert->velocity_smooth, vert->velocity);
+//                          BKE_sim_debug_data_add_vector(grid->debug_data, wloc, dvel, 1, 1, 1, "grid", 5566, i, j, k);
+            }
+
+            if (!is_margin) {
+              float d = CLAMPIS(vert->density * grid->debug2, 0.0f, 1.0f);
+              float col0[3] = {0.3, 0.3, 0.3};
+              float colp[3] = {0.0, 0.0, 1.0};
+              float col[3];
+
+              interp_v3_v3v3(col, col0, colp, d);
+//                          if (d > 0.05f)
+//                              BKE_sim_debug_data_add_dot(grid->debug_data, wloc, col[0], col[1], col[2], "grid", 5544, i, j, k);
+            }
+          }
+        }
+      }
+    }
 #endif
 
-		return true;
-	}
-	else {
-		/* Clear result in case of error */
-		for (i = 0, vert = grid->verts; i < num_cells; ++i, ++vert) {
-			zero_v3(vert->velocity_smooth);
-		}
+    return true;
+  }
+  else {
+    /* Clear result in case of error */
+    for (i = 0, vert = grid->verts; i < num_cells; ++i, ++vert) {
+      zero_v3(vert->velocity_smooth);
+    }
 
-		return false;
-	}
+    return false;
+  }
 }
 
 #if 0 /* XXX weighting is incorrect, disabled for now */
@@ -893,209 +966,216 @@ bool BPH_hair_volume_solve_divergence(HairGrid *grid, float /*dt*/, float target
 
 BLI_INLINE void hair_volume_filter_box_convolute(HairVertexGrid *grid, float invD, const int kernel_size[3], int i, int j, int k)
 {
-	int res = grid->res;
-	int p, q, r;
-	int minp = max_ii(i - kernel_size[0], 0), maxp = min_ii(i + kernel_size[0], res - 1);
-	int minq = max_ii(j - kernel_size[1], 0), maxq = min_ii(j + kernel_size[1], res - 1);
-	int minr = max_ii(k - kernel_size[2], 0), maxr = min_ii(k + kernel_size[2], res - 1);
-	int offset, kernel_offset, kernel_dq, kernel_dr;
-	HairGridVert *verts;
-	float *vel_smooth;
-
-	offset = i + (j + k * res) * res;
-	verts = grid->verts;
-	vel_smooth = verts[offset].velocity_smooth;
-
-	kernel_offset = minp + (minq + minr * res) * res;
-	kernel_dq = res;
-	kernel_dr = res * res;
-	for (r = minr; r <= maxr; ++r) {
-		for (q = minq; q <= maxq; ++q) {
-			for (p = minp; p <= maxp; ++p) {
-
-				madd_v3_v3fl(vel_smooth, verts[kernel_offset].velocity, invD);
-
-				kernel_offset += 1;
-			}
-			kernel_offset += kernel_dq;
-		}
-		kernel_offset += kernel_dr;
-	}
+  int res = grid->res;
+  int p, q, r;
+  int minp = max_ii(i - kernel_size[0], 0), maxp = min_ii(i + kernel_size[0], res - 1);
+  int minq = max_ii(j - kernel_size[1], 0), maxq = min_ii(j + kernel_size[1], res - 1);
+  int minr = max_ii(k - kernel_size[2], 0), maxr = min_ii(k + kernel_size[2], res - 1);
+  int offset, kernel_offset, kernel_dq, kernel_dr;
+  HairGridVert *verts;
+  float *vel_smooth;
+
+  offset = i + (j + k * res) * res;
+  verts = grid->verts;
+  vel_smooth = verts[offset].velocity_smooth;
+
+  kernel_offset = minp + (minq + minr * res) * res;
+  kernel_dq = res;
+  kernel_dr = res * res;
+  for (r = minr; r <= maxr; ++r) {
+    for (q = minq; q <= maxq; ++q) {
+      for (p = minp; p <= maxp; ++p) {
+
+        madd_v3_v3fl(vel_smooth, verts[kernel_offset].velocity, invD);
+
+        kernel_offset += 1;
+      }
+      kernel_offset += kernel_dq;
+    }
+    kernel_offset += kernel_dr;
+  }
 }
 
 void BPH_hair_volume_vertex_grid_filter_box(HairVertexGrid *grid, int kernel_size)
 {
-	int size = hair_grid_size(grid->res);
-	int kernel_sizev[3] = {kernel_size, kernel_size, kernel_size};
-	int tot;
-	float invD;
-	int i, j, k;
-
-	if (kernel_size <= 0)
-		return;
-
-	tot = kernel_size * 2 + 1;
-	invD = 1.0f / (float)(tot * tot * tot);
-
-	/* clear values for convolution */
-	for (i = 0; i < size; ++i) {
-		zero_v3(grid->verts[i].velocity_smooth);
-	}
-
-	for (i = 0; i < grid->res; ++i) {
-		for (j = 0; j < grid->res; ++j) {
-			for (k = 0; k < grid->res; ++k) {
-				hair_volume_filter_box_convolute(grid, invD, kernel_sizev, i, j, k);
-			}
-		}
-	}
-
-	/* apply as new velocity */
-	for (i = 0; i < size; ++i) {
-		copy_v3_v3(grid->verts[i].velocity, grid->verts[i].velocity_smooth);
-	}
+  int size = hair_grid_size(grid->res);
+  int kernel_sizev[3] = {kernel_size, kernel_size, kernel_size};
+  int tot;
+  float invD;
+  int i, j, k;
+
+  if (kernel_size <= 0)
+    return;
+
+  tot = kernel_size * 2 + 1;
+  invD = 1.0f / (float)(tot * tot * tot);
+
+  /* clear values for convolution */
+  for (i = 0; i < size; ++i) {
+    zero_v3(grid->verts[i].velocity_smooth);
+  }
+
+  for (i = 0; i < grid->res; ++i) {
+    for (j = 0; j < grid->res; ++j) {
+      for (k = 0; k < grid->res; ++k) {
+        hair_volume_filter_box_convolute(grid, invD, kernel_sizev, i, j, k);
+      }
+    }
+  }
+
+  /* apply as new velocity */
+  for (i = 0; i < size; ++i) {
+    copy_v3_v3(grid->verts[i].velocity, grid->verts[i].velocity_smooth);
+  }
 }
 #endif
 
-HairGrid *BPH_hair_volume_create_vertex_grid(float cellsize, const float gmin[3], const float gmax[3])
+HairGrid *BPH_hair_volume_create_vertex_grid(float cellsize,
+                                             const float gmin[3],
+                                             const float gmax[3])
 {
-	float scale;
-	float extent[3];
-	int resmin[3], resmax[3], res[3];
-	float gmin_margin[3], gmax_margin[3];
-	int size;
-	HairGrid *grid;
-	int i;
-
-	/* sanity check */
-	if (cellsize <= 0.0f)
-		cellsize = 1.0f;
-	scale = 1.0f / cellsize;
-
-	sub_v3_v3v3(extent, gmax, gmin);
-	for (i = 0; i < 3; ++i) {
-		resmin[i] = floor_int(gmin[i] * scale);
-		resmax[i] = floor_int(gmax[i] * scale) + 1;
-
-		/* add margin of 1 cell */
-		resmin[i] -= 1;
-		resmax[i] += 1;
-
-		res[i] = resmax[i] - resmin[i] + 1;
-		/* sanity check: avoid null-sized grid */
-		if (res[i] < 4) {
-			res[i] = 4;
-			resmax[i] = resmin[i] + 4;
-		}
-		/* sanity check: avoid too large grid size */
-		if (res[i] > MAX_HAIR_GRID_RES) {
-			res[i] = MAX_HAIR_GRID_RES;
-			resmax[i] = resmin[i] + MAX_HAIR_GRID_RES;
-		}
-
-		gmin_margin[i] = (float)resmin[i] * cellsize;
-		gmax_margin[i] = (float)resmax[i] * cellsize;
-	}
-	size = hair_grid_size(res);
-
-	grid = (HairGrid *)MEM_callocN(sizeof(HairGrid), "hair grid");
-	grid->res[0] = res[0];
-	grid->res[1] = res[1];
-	grid->res[2] = res[2];
-	copy_v3_v3(grid->gmin, gmin_margin);
-	copy_v3_v3(grid->gmax, gmax_margin);
-	grid->cellsize = cellsize;
-	grid->inv_cellsize = scale;
-	grid->verts = (HairGridVert *)MEM_callocN(sizeof(HairGridVert) * size, "hair voxel data");
-
-	return grid;
+  float scale;
+  float extent[3];
+  int resmin[3], resmax[3], res[3];
+  float gmin_margin[3], gmax_margin[3];
+  int size;
+  HairGrid *grid;
+  int i;
+
+  /* sanity check */
+  if (cellsize <= 0.0f)
+    cellsize = 1.0f;
+  scale = 1.0f / cellsize;
+
+  sub_v3_v3v3(extent, gmax, gmin);
+  for (i = 0; i < 3; ++i) {
+    resmin[i] = floor_int(gmin[i] * scale);
+    resmax[i] = floor_int(gmax[i] * scale) + 1;
+
+    /* add margin of 1 cell */
+    resmin[i] -= 1;
+    resmax[i] += 1;
+
+    res[i] = resmax[i] - resmin[i] + 1;
+    /* sanity check: avoid null-sized grid */
+    if (res[i] < 4) {
+      res[i] = 4;
+      resmax[i] = resmin[i] + 4;
+    }
+    /* sanity check: avoid too large grid size */
+    if (res[i] > MAX_HAIR_GRID_RES) {
+      res[i] = MAX_HAIR_GRID_RES;
+      resmax[i] = resmin[i] + MAX_HAIR_GRID_RES;
+    }
+
+    gmin_margin[i] = (float)resmin[i] * cellsize;
+    gmax_margin[i] = (float)resmax[i] * cellsize;
+  }
+  size = hair_grid_size(res);
+
+  grid = (HairGrid *)MEM_callocN(sizeof(HairGrid), "hair grid");
+  grid->res[0] = res[0];
+  grid->res[1] = res[1];
+  grid->res[2] = res[2];
+  copy_v3_v3(grid->gmin, gmin_margin);
+  copy_v3_v3(grid->gmax, gmax_margin);
+  grid->cellsize = cellsize;
+  grid->inv_cellsize = scale;
+  grid->verts = (HairGridVert *)MEM_callocN(sizeof(HairGridVert) * size, "hair voxel data");
+
+  return grid;
 }
 
 void BPH_hair_volume_free_vertex_grid(HairGrid *grid)
 {
-	if (grid) {
-		if (grid->verts)
-			MEM_freeN(grid->verts);
-		MEM_freeN(grid);
-	}
+  if (grid) {
+    if (grid->verts)
+      MEM_freeN(grid->verts);
+    MEM_freeN(grid);
+  }
 }
 
-void BPH_hair_volume_grid_geometry(HairGrid *grid, float *cellsize, int res[3], float gmin[3], float gmax[3])
+void BPH_hair_volume_grid_geometry(
+    HairGrid *grid, float *cellsize, int res[3], float gmin[3], float gmax[3])
 {
-	if (cellsize) *cellsize = grid->cellsize;
-	if (res) copy_v3_v3_int(res, grid->res);
-	if (gmin) copy_v3_v3(gmin, grid->gmin);
-	if (gmax) copy_v3_v3(gmax, grid->gmax);
+  if (cellsize)
+    *cellsize = grid->cellsize;
+  if (res)
+    copy_v3_v3_int(res, grid->res);
+  if (gmin)
+    copy_v3_v3(gmin, grid->gmin);
+  if (gmax)
+    copy_v3_v3(gmax, grid->gmax);
 }
 
 #if 0
 static HairGridVert *hair_volume_create_collision_grid(ClothModifierData *clmd, lfVector *lX, unsigned int numverts)
 {
-	int res = hair_grid_res;
-	int size = hair_grid_size(res);
-	HairGridVert *collgrid;
-	ListBase *colliders;
-	ColliderCache *col = NULL;
-	float gmin[3], gmax[3], scale[3];
-	/* 2.0f is an experimental value that seems to give good results */
-	float collfac = 2.0f * clmd->sim_parms->collider_friction;
-	unsigned int v = 0;
-	int i = 0;
-
-	hair_volume_get_boundbox(lX, numverts, gmin, gmax);
-	hair_grid_get_scale(res, gmin, gmax, scale);
-
-	collgrid = MEM_mallocN(sizeof(HairGridVert) * size, "hair collider voxel data");
-
-	/* initialize grid */
-	for (i = 0; i < size; ++i) {
-		zero_v3(collgrid[i].velocity);
-		collgrid[i].density = 0.0f;
-	}
-
-	/* gather colliders */
-	colliders = BKE_collider_cache_create(depsgraph, NULL, NULL);
-	if (colliders && collfac > 0.0f) {
-		for (col = colliders->first; col; col = col->next) {
-			MVert *loc0 = col->collmd->x;
-			MVert *loc1 = col->collmd->xnew;
-			float vel[3];
-			float weights[8];
-			int di, dj, dk;
-
-			for (v = 0; v < col->collmd->numverts; v++, loc0++, loc1++) {
-				int offset;
-
-				if (!hair_grid_point_valid(loc1->co, gmin, gmax))
-					continue;
-
-				offset = hair_grid_weights(res, gmin, scale, lX[v], weights);
-
-				sub_v3_v3v3(vel, loc1->co, loc0->co);
-
-				for (di = 0; di < 2; ++di) {
-					for (dj = 0; dj < 2; ++dj) {
-						for (dk = 0; dk < 2; ++dk) {
-							int voffset = offset + di + (dj + dk * res) * res;
-							int iw = di + dj * 2 + dk * 4;
-
-							collgrid[voffset].density += weights[iw];
-							madd_v3_v3fl(collgrid[voffset].velocity, vel, weights[iw]);
-						}
-					}
-				}
-			}
-		}
-	}
-	BKE_collider_cache_free(&colliders);
-
-	/* divide velocity with density */
-	for (i = 0; i < size; i++) {
-		float density = collgrid[i].density;
-		if (density > 0.0f)
-			mul_v3_fl(collgrid[i].velocity, 1.0f / density);
-	}
-
-	return collgrid;
+  int res = hair_grid_res;
+  int size = hair_grid_size(res);
+  HairGridVert *collgrid;
+  ListBase *colliders;
+  ColliderCache *col = NULL;
+  float gmin[3], gmax[3], scale[3];
+  /* 2.0f is an experimental value that seems to give good results */
+  float collfac = 2.0f * clmd->sim_parms->collider_friction;
+  unsigned int v = 0;
+  int i = 0;
+
+  hair_volume_get_boundbox(lX, numverts, gmin, gmax);
+  hair_grid_get_scale(res, gmin, gmax, scale);
+
+  collgrid = MEM_mallocN(sizeof(HairGridVert) * size, "hair collider voxel data");
+
+  /* initialize grid */
+  for (i = 0; i < size; ++i) {
+    zero_v3(collgrid[i].velocity);
+    collgrid[i].density = 0.0f;
+  }
+
+  /* gather colliders */
+  colliders = BKE_collider_cache_create(depsgraph, NULL, NULL);
+  if (colliders && collfac > 0.0f) {
+    for (col = colliders->first; col; col = col->next) {
+      MVert *loc0 = col->collmd->x;
+      MVert *loc1 = col->collmd->xnew;
+      float vel[3];
+      float weights[8];
+      int di, dj, dk;
+
+      for (v = 0; v < col->collmd->numverts; v++, loc0++, loc1++) {
+        int offset;
+
+        if (!hair_grid_point_valid(loc1->co, gmin, gmax))
+          continue;
+
+        offset = hair_grid_weights(res, gmin, scale, lX[v], weights);
+
+        sub_v3_v3v3(vel, loc1->co, loc0->co);
+
+        for (di = 0; di < 2; ++di) {
+          for (dj = 0; dj < 2; ++dj) {
+            for (dk = 0; dk < 2; ++dk) {
+              int voffset = offset + di + (dj + dk * res) * res;
+              int iw = di + dj * 2 + dk * 4;
+
+              collgrid[voffset].density += weights[iw];
+              madd_v3_v3fl(collgrid[voffset].velocity, vel, weights[iw]);
+            }
+          }
+        }
+      }
+    }
+  }
+  BKE_collider_cache_free(&colliders);
+
+  /* divide velocity with density */
+  for (i = 0; i < size; i++) {
+    float density = collgrid[i].density;
+    if (density > 0.0f)
+      mul_v3_fl(collgrid[i].velocity, 1.0f / density);
+  }
+
+  return collgrid;
 }
 #endif
diff --git a/source/blender/physics/intern/implicit.h b/source/blender/physics/intern/implicit.h
index eac59a3edbb..a88a5785fee 100644
--- a/source/blender/physics/intern/implicit.h
+++ b/source/blender/physics/intern/implicit.h
@@ -54,24 +54,30 @@ extern "C" {
 struct Implicit_Data;
 
 typedef struct ImplicitSolverResult {
-	int status;
+  int status;
 
-	int iterations;
-	float error;
+  int iterations;
+  float error;
 } ImplicitSolverResult;
 
 BLI_INLINE void implicit_print_matrix_elem(float v)
 {
-	printf("%-8.3f", v);
+  printf("%-8.3f", v);
 }
 
 void BPH_mass_spring_set_vertex_mass(struct Implicit_Data *data, int index, float mass);
 void BPH_mass_spring_set_rest_transform(struct Implicit_Data *data, int index, float rot[3][3]);
 
-void BPH_mass_spring_set_motion_state(struct Implicit_Data *data, int index, const float x[3], const float v[3]);
+void BPH_mass_spring_set_motion_state(struct Implicit_Data *data,
+                                      int index,
+                                      const float x[3],
+                                      const float v[3]);
 void BPH_mass_spring_set_position(struct Implicit_Data *data, int index, const float x[3]);
 void BPH_mass_spring_set_velocity(struct Implicit_Data *data, int index, const float v[3]);
-void BPH_mass_spring_get_motion_state(struct Implicit_Data *data, int index, float x[3], float v[3]);
+void BPH_mass_spring_get_motion_state(struct Implicit_Data *data,
+                                      int index,
+                                      float x[3],
+                                      float v[3]);
 void BPH_mass_spring_get_position(struct Implicit_Data *data, int index, float x[3]);
 
 /* access to modified motion state during solver step */
@@ -81,46 +87,100 @@ void BPH_mass_spring_get_new_velocity(struct Implicit_Data *data, int index, flo
 void BPH_mass_spring_set_new_velocity(struct Implicit_Data *data, int index, const float v[3]);
 
 void BPH_mass_spring_clear_constraints(struct Implicit_Data *data);
-void BPH_mass_spring_add_constraint_ndof0(struct Implicit_Data *data, int index, const float dV[3]);
-void BPH_mass_spring_add_constraint_ndof1(struct Implicit_Data *data, int index, const float c1[3], const float c2[3], const float dV[3]);
-void BPH_mass_spring_add_constraint_ndof2(struct Implicit_Data *data, int index, const float c1[3], const float dV[3]);
-
-bool BPH_mass_spring_solve_velocities(struct Implicit_Data *data, float dt, struct ImplicitSolverResult *result);
+void BPH_mass_spring_add_constraint_ndof0(struct Implicit_Data *data,
+                                          int index,
+                                          const float dV[3]);
+void BPH_mass_spring_add_constraint_ndof1(struct Implicit_Data *data,
+                                          int index,
+                                          const float c1[3],
+                                          const float c2[3],
+                                          const float dV[3]);
+void BPH_mass_spring_add_constraint_ndof2(struct Implicit_Data *data,
+                                          int index,
+                                          const float c1[3],
+                                          const float dV[3]);
+
+bool BPH_mass_spring_solve_velocities(struct Implicit_Data *data,
+                                      float dt,
+                                      struct ImplicitSolverResult *result);
 bool BPH_mass_spring_solve_positions(struct Implicit_Data *data, float dt);
 void BPH_mass_spring_apply_result(struct Implicit_Data *data);
 
 /* Clear the force vector at the beginning of the time step */
 void BPH_mass_spring_clear_forces(struct Implicit_Data *data);
 /* Fictitious forces introduced by moving coordinate systems */
-void BPH_mass_spring_force_reference_frame(struct Implicit_Data *data, int index, const float acceleration[3], const float omega[3], const float domega_dt[3], float mass);
+void BPH_mass_spring_force_reference_frame(struct Implicit_Data *data,
+                                           int index,
+                                           const float acceleration[3],
+                                           const float omega[3],
+                                           const float domega_dt[3],
+                                           float mass);
 /* Simple uniform gravity force */
-void BPH_mass_spring_force_gravity(struct Implicit_Data *data, int index, float mass, const float g[3]);
+void BPH_mass_spring_force_gravity(struct Implicit_Data *data,
+                                   int index,
+                                   float mass,
+                                   const float g[3]);
 /* Global drag force (velocity damping) */
 void BPH_mass_spring_force_drag(struct Implicit_Data *data, float drag);
 /* Custom external force */
-void BPH_mass_spring_force_extern(struct Implicit_Data *data, int i, const float f[3], float dfdx[3][3], float dfdv[3][3]);
+void BPH_mass_spring_force_extern(
+    struct Implicit_Data *data, int i, const float f[3], float dfdx[3][3], float dfdv[3][3]);
 /* Wind force, acting on a face */
-void BPH_mass_spring_force_face_wind(struct Implicit_Data *data, int v1, int v2, int v3, const float(*winvec)[3]);
+void BPH_mass_spring_force_face_wind(
+    struct Implicit_Data *data, int v1, int v2, int v3, const float (*winvec)[3]);
 /* Wind force, acting on an edge */
-void BPH_mass_spring_force_edge_wind(struct Implicit_Data *data, int v1, int v2, float radius1, float radius2, const float(*winvec)[3]);
+void BPH_mass_spring_force_edge_wind(struct Implicit_Data *data,
+                                     int v1,
+                                     int v2,
+                                     float radius1,
+                                     float radius2,
+                                     const float (*winvec)[3]);
 /* Wind force, acting on a vertex */
-void BPH_mass_spring_force_vertex_wind(struct Implicit_Data *data, int v, float radius, const float(*winvec)[3]);
+void BPH_mass_spring_force_vertex_wind(struct Implicit_Data *data,
+                                       int v,
+                                       float radius,
+                                       const float (*winvec)[3]);
 /* Linear spring force between two points */
-bool BPH_mass_spring_force_spring_linear(struct Implicit_Data *data, int i, int j, float restlen,
-                                         float stiffness_tension, float damping_tension,
-                                         float stiffness_compression, float damping_compression,
-                                         bool resist_compress, bool new_compress, float clamp_force);
+bool BPH_mass_spring_force_spring_linear(struct Implicit_Data *data,
+                                         int i,
+                                         int j,
+                                         float restlen,
+                                         float stiffness_tension,
+                                         float damping_tension,
+                                         float stiffness_compression,
+                                         float damping_compression,
+                                         bool resist_compress,
+                                         bool new_compress,
+                                         float clamp_force);
 /* Angular spring force between two polygons */
-bool BPH_mass_spring_force_spring_angular(struct Implicit_Data *data, int i, int j, int *i_a, int *i_b, int len_a, int len_b,
-                                          float restang, float stiffness, float damping);
+bool BPH_mass_spring_force_spring_angular(struct Implicit_Data *data,
+                                          int i,
+                                          int j,
+                                          int *i_a,
+                                          int *i_b,
+                                          int len_a,
+                                          int len_b,
+                                          float restang,
+                                          float stiffness,
+                                          float damping);
 /* Bending force, forming a triangle at the base of two structural springs */
-bool BPH_mass_spring_force_spring_bending(struct Implicit_Data *data, int i, int j, float restlen, float kb, float cb);
+bool BPH_mass_spring_force_spring_bending(
+    struct Implicit_Data *data, int i, int j, float restlen, float kb, float cb);
 /* Angular bending force based on local target vectors */
-bool BPH_mass_spring_force_spring_bending_hair(struct Implicit_Data *data, int i, int j, int k,
-                                               const float target[3], float stiffness, float damping);
+bool BPH_mass_spring_force_spring_bending_hair(struct Implicit_Data *data,
+                                               int i,
+                                               int j,
+                                               int k,
+                                               const float target[3],
+                                               float stiffness,
+                                               float damping);
 /* Global goal spring */
-bool BPH_mass_spring_force_spring_goal(struct Implicit_Data *data, int i, const float goal_x[3], const float goal_v[3],
-                                       float stiffness, float damping);
+bool BPH_mass_spring_force_spring_goal(struct Implicit_Data *data,
+                                       int i,
+                                       const float goal_x[3],
+                                       const float goal_v[3],
+                                       float stiffness,
+                                       float damping);
 
 /* ======== Hair Volumetric Forces ======== */
 
@@ -130,44 +190,67 @@ struct VoxelData;
 
 #define MAX_HAIR_GRID_RES 256
 
-struct HairGrid *BPH_hair_volume_create_vertex_grid(float cellsize, const float gmin[3], const float gmax[3]);
+struct HairGrid *BPH_hair_volume_create_vertex_grid(float cellsize,
+                                                    const float gmin[3],
+                                                    const float gmax[3]);
 void BPH_hair_volume_free_vertex_grid(struct HairGrid *grid);
-void BPH_hair_volume_grid_geometry(struct HairGrid *grid, float *cellsize, int res[3], float gmin[3], float gmax[3]);
+void BPH_hair_volume_grid_geometry(
+    struct HairGrid *grid, float *cellsize, int res[3], float gmin[3], float gmax[3]);
 
 void BPH_hair_volume_grid_clear(struct HairGrid *grid);
 void BPH_hair_volume_add_vertex(struct HairGrid *grid, const float x[3], const float v[3]);
 void BPH_hair_volume_add_segment(struct HairGrid *grid,
-                                 const float x1[3], const float v1[3], const float x2[3], const float v2[3],
-                                 const float x3[3], const float v3[3], const float x4[3], const float v4[3],
-                                 const float dir1[3], const float dir2[3], const float dir3[3]);
+                                 const float x1[3],
+                                 const float v1[3],
+                                 const float x2[3],
+                                 const float v2[3],
+                                 const float x3[3],
+                                 const float v3[3],
+                                 const float x4[3],
+                                 const float v4[3],
+                                 const float dir1[3],
+                                 const float dir2[3],
+                                 const float dir3[3]);
 
 void BPH_hair_volume_normalize_vertex_grid(struct HairGrid *grid);
 
-bool BPH_hair_volume_solve_divergence(struct HairGrid *grid, float dt, float target_density, float target_strength);
+bool BPH_hair_volume_solve_divergence(struct HairGrid *grid,
+                                      float dt,
+                                      float target_density,
+                                      float target_strength);
 #if 0 /* XXX weighting is incorrect, disabled for now */
 void BPH_hair_volume_vertex_grid_filter_box(struct HairVertexGrid *grid, int kernel_size);
 #endif
 
-void BPH_hair_volume_grid_interpolate(struct HairGrid *grid, const float x[3],
-                                      float *density, float velocity[3], float velocity_smooth[3],
-                                      float density_gradient[3], float velocity_gradient[3][3]);
+void BPH_hair_volume_grid_interpolate(struct HairGrid *grid,
+                                      const float x[3],
+                                      float *density,
+                                      float velocity[3],
+                                      float velocity_smooth[3],
+                                      float density_gradient[3],
+                                      float velocity_gradient[3][3]);
 
 /* Effect of fluid simulation grid on velocities.
  * fluid_factor controls blending between PIC (Particle-in-Cell)
  *     and FLIP (Fluid-Implicit-Particle) methods (0 = only PIC, 1 = only FLIP)
  */
-void BPH_hair_volume_grid_velocity(struct HairGrid *grid, const float x[3], const float v[3],
-                                   float fluid_factor,
-                                   float r_v[3]);
+void BPH_hair_volume_grid_velocity(
+    struct HairGrid *grid, const float x[3], const float v[3], float fluid_factor, float r_v[3]);
 /* XXX Warning: expressing grid effects on velocity as a force is not very stable,
  * due to discontinuities in interpolated values!
  * Better use hybrid approaches such as described in
  * "Detail Preserving Continuum Simulation of Straight Hair"
  * (McAdams, Selle 2009)
  */
-void BPH_hair_volume_vertex_grid_forces(struct HairGrid *grid, const float x[3], const float v[3],
-                                        float smoothfac, float pressurefac, float minpressure,
-                                        float f[3], float dfdx[3][3], float dfdv[3][3]);
+void BPH_hair_volume_vertex_grid_forces(struct HairGrid *grid,
+                                        const float x[3],
+                                        const float v[3],
+                                        float smoothfac,
+                                        float pressurefac,
+                                        float minpressure,
+                                        float f[3],
+                                        float dfdx[3][3],
+                                        float dfdv[3][3]);
 
 #ifdef __cplusplus
 }
diff --git a/source/blender/physics/intern/implicit_blender.c b/source/blender/physics/intern/implicit_blender.c
index 83f586c4078..622a7093fd4 100644
--- a/source/blender/physics/intern/implicit_blender.c
+++ b/source/blender/physics/intern/implicit_blender.c
@@ -25,48 +25,48 @@
 
 #ifdef IMPLICIT_SOLVER_BLENDER
 
-#include "MEM_guardedalloc.h"
+#  include "MEM_guardedalloc.h"
 
-#include "DNA_scene_types.h"
-#include "DNA_object_types.h"
-#include "DNA_object_force_types.h"
-#include "DNA_meshdata_types.h"
-#include "DNA_texture_types.h"
+#  include "DNA_scene_types.h"
+#  include "DNA_object_types.h"
+#  include "DNA_object_force_types.h"
+#  include "DNA_meshdata_types.h"
+#  include "DNA_texture_types.h"
 
-#include "BLI_math.h"
-#include "BLI_utildefines.h"
+#  include "BLI_math.h"
+#  include "BLI_utildefines.h"
 
-#include "BKE_cloth.h"
-#include "BKE_collision.h"
-#include "BKE_effect.h"
+#  include "BKE_cloth.h"
+#  include "BKE_collision.h"
+#  include "BKE_effect.h"
 
-#include "BPH_mass_spring.h"
+#  include "BPH_mass_spring.h"
 
-#ifdef __GNUC__
-#  pragma GCC diagnostic ignored "-Wtype-limits"
-#endif
+#  ifdef __GNUC__
+#    pragma GCC diagnostic ignored "-Wtype-limits"
+#  endif
 
-#ifdef _OPENMP
-#  define CLOTH_OPENMP_LIMIT 512
-#endif
+#  ifdef _OPENMP
+#    define CLOTH_OPENMP_LIMIT 512
+#  endif
 
 //#define DEBUG_TIME
 
-#ifdef DEBUG_TIME
-#  include "PIL_time.h"
-#endif
+#  ifdef DEBUG_TIME
+#    include "PIL_time.h"
+#  endif
 
 static float I[3][3] = {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}};
 static float ZERO[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};
 
-#if 0
-#define C99
-#ifdef C99
-#defineDO_INLINE inline
-#else
-#defineDO_INLINE static
-#endif
-#endif  /* if 0 */
+#  if 0
+#    define C99
+#    ifdef C99
+#      defineDO_INLINE inline
+#    else
+#      defineDO_INLINE static
+#    endif
+#  endif /* if 0 */
 
 struct Cloth;
 
@@ -77,12 +77,12 @@ struct Cloth;
 /* DEFINITIONS */
 typedef float lfVector[3];
 typedef struct fmatrix3x3 {
-	float m[3][3]; /* 3x3 matrix */
-	unsigned int c, r; /* column and row number */
-	/* int pinned; // is this vertex allowed to move? */
-	float n1, n2, n3; /* three normal vectors for collision constrains */
-	unsigned int vcount; /* vertex count */
-	unsigned int scount; /* spring count */
+  float m[3][3];     /* 3x3 matrix */
+  unsigned int c, r; /* column and row number */
+  /* int pinned; // is this vertex allowed to move? */
+  float n1, n2, n3;    /* three normal vectors for collision constrains */
+  unsigned int vcount; /* vertex count */
+  unsigned int scount; /* spring count */
 } fmatrix3x3;
 
 ///////////////////////////
@@ -92,34 +92,34 @@ typedef struct fmatrix3x3 {
 /* STATUS: verified */
 DO_INLINE void mul_fvector_S(float to[3], float from[3], float scalar)
 {
-	to[0] = from[0] * scalar;
-	to[1] = from[1] * scalar;
-	to[2] = from[2] * scalar;
+  to[0] = from[0] * scalar;
+  to[1] = from[1] * scalar;
+  to[2] = from[2] * scalar;
 }
 /* simple v^T * v product ("outer product") */
 /* STATUS: HAS TO BE verified (*should* work) */
 DO_INLINE void mul_fvectorT_fvector(float to[3][3], float vectorA[3], float vectorB[3])
 {
-	mul_fvector_S(to[0], vectorB, vectorA[0]);
-	mul_fvector_S(to[1], vectorB, vectorA[1]);
-	mul_fvector_S(to[2], vectorB, vectorA[2]);
+  mul_fvector_S(to[0], vectorB, vectorA[0]);
+  mul_fvector_S(to[1], vectorB, vectorA[1]);
+  mul_fvector_S(to[2], vectorB, vectorA[2]);
 }
 /* simple v^T * v product with scalar ("outer product") */
 /* STATUS: HAS TO BE verified (*should* work) */
 DO_INLINE void mul_fvectorT_fvectorS(float to[3][3], float vectorA[3], float vectorB[3], float aS)
 {
-	mul_fvectorT_fvector(to, vectorA, vectorB);
+  mul_fvectorT_fvector(to, vectorA, vectorB);
 
-	mul_fvector_S(to[0], to[0], aS);
-	mul_fvector_S(to[1], to[1], aS);
-	mul_fvector_S(to[2], to[2], aS);
+  mul_fvector_S(to[0], to[0], aS);
+  mul_fvector_S(to[1], to[1], aS);
+  mul_fvector_S(to[2], to[2], aS);
 }
 
-#if 0
+#  if 0
 /* printf vector[3] on console: for debug output */
 static void print_fvector(float m3[3])
 {
-	printf("%f\n%f\n%f\n\n", m3[0], m3[1], m3[2]);
+  printf("%f\n%f\n%f\n\n", m3[0], m3[1], m3[2]);
 }
 
 ///////////////////////////
@@ -128,317 +128,341 @@ static void print_fvector(float m3[3])
 /* print long vector on console: for debug output */
 DO_INLINE void print_lfvector(float(*fLongVector)[3], unsigned int verts)
 {
-	unsigned int i = 0;
-	for (i = 0; i < verts; i++) {
-		print_fvector(fLongVector[i]);
-	}
+  unsigned int i = 0;
+  for (i = 0; i < verts; i++) {
+    print_fvector(fLongVector[i]);
+  }
 }
-#endif
+#  endif
 
 /* create long vector */
 DO_INLINE lfVector *create_lfvector(unsigned int verts)
 {
-	/* TODO: check if memory allocation was successful */
-	return (lfVector *)MEM_callocN(verts * sizeof(lfVector), "cloth_implicit_alloc_vector");
-	// return (lfVector *)cloth_aligned_malloc(&MEMORY_BASE, verts * sizeof(lfVector));
+  /* TODO: check if memory allocation was successful */
+  return (lfVector *)MEM_callocN(verts * sizeof(lfVector), "cloth_implicit_alloc_vector");
+  // return (lfVector *)cloth_aligned_malloc(&MEMORY_BASE, verts * sizeof(lfVector));
 }
 /* delete long vector */
-DO_INLINE void del_lfvector(float(*fLongVector)[3])
+DO_INLINE void del_lfvector(float (*fLongVector)[3])
 {
-	if (fLongVector != NULL) {
-		MEM_freeN(fLongVector);
-		// cloth_aligned_free(&MEMORY_BASE, fLongVector);
-	}
+  if (fLongVector != NULL) {
+    MEM_freeN(fLongVector);
+    // cloth_aligned_free(&MEMORY_BASE, fLongVector);
+  }
 }
 /* copy long vector */
-DO_INLINE void cp_lfvector(float(*to)[3], float(*from)[3], unsigned int verts)
+DO_INLINE void cp_lfvector(float (*to)[3], float (*from)[3], unsigned int verts)
 {
-	memcpy(to, from, verts * sizeof(lfVector));
+  memcpy(to, from, verts * sizeof(lfVector));
 }
 /* init long vector with float[3] */
-DO_INLINE void init_lfvector(float(*fLongVector)[3], float vector[3], unsigned int verts)
+DO_INLINE void init_lfvector(float (*fLongVector)[3], float vector[3], unsigned int verts)
 {
-	unsigned int i = 0;
-	for (i = 0; i < verts; i++) {
-		copy_v3_v3(fLongVector[i], vector);
-	}
+  unsigned int i = 0;
+  for (i = 0; i < verts; i++) {
+    copy_v3_v3(fLongVector[i], vector);
+  }
 }
 /* zero long vector with float[3] */
-DO_INLINE void zero_lfvector(float(*to)[3], unsigned int verts)
+DO_INLINE void zero_lfvector(float (*to)[3], unsigned int verts)
 {
-	memset(to, 0.0f, verts * sizeof(lfVector));
+  memset(to, 0.0f, verts * sizeof(lfVector));
 }
 /* multiply long vector with scalar*/
-DO_INLINE void mul_lfvectorS(float(*to)[3], float(*fLongVector)[3], float scalar, unsigned int verts)
+DO_INLINE void mul_lfvectorS(float (*to)[3],
+                             float (*fLongVector)[3],
+                             float scalar,
+                             unsigned int verts)
 {
-	unsigned int i = 0;
+  unsigned int i = 0;
 
-	for (i = 0; i < verts; i++) {
-		mul_fvector_S(to[i], fLongVector[i], scalar);
-	}
+  for (i = 0; i < verts; i++) {
+    mul_fvector_S(to[i], fLongVector[i], scalar);
+  }
 }
 /* multiply long vector with scalar*/
 /* A -= B * float */
-DO_INLINE void submul_lfvectorS(float(*to)[3], float(*fLongVector)[3], float scalar, unsigned int verts)
+DO_INLINE void submul_lfvectorS(float (*to)[3],
+                                float (*fLongVector)[3],
+                                float scalar,
+                                unsigned int verts)
 {
-	unsigned int i = 0;
-	for (i = 0; i < verts; i++) {
-		VECSUBMUL(to[i], fLongVector[i], scalar);
-	}
+  unsigned int i = 0;
+  for (i = 0; i < verts; i++) {
+    VECSUBMUL(to[i], fLongVector[i], scalar);
+  }
 }
 /* dot product for big vector */
-DO_INLINE float dot_lfvector(float(*fLongVectorA)[3], float(*fLongVectorB)[3], unsigned int verts)
-{
-	long i = 0;
-	float temp = 0.0;
-// XXX brecht, disabled this for now (first schedule line was already disabled),
-// due to non-commutative nature of floating point ops this makes the sim give
-// different results each time you run it!
-// schedule(guided, 2)
-//#pragma omp parallel for reduction(+: temp) if (verts > CLOTH_OPENMP_LIMIT)
-	for (i = 0; i < (long)verts; i++) {
-		temp += dot_v3v3(fLongVectorA[i], fLongVectorB[i]);
-	}
-	return temp;
+DO_INLINE float dot_lfvector(float (*fLongVectorA)[3],
+                             float (*fLongVectorB)[3],
+                             unsigned int verts)
+{
+  long i = 0;
+  float temp = 0.0;
+  // XXX brecht, disabled this for now (first schedule line was already disabled),
+  // due to non-commutative nature of floating point ops this makes the sim give
+  // different results each time you run it!
+  // schedule(guided, 2)
+  //#pragma omp parallel for reduction(+: temp) if (verts > CLOTH_OPENMP_LIMIT)
+  for (i = 0; i < (long)verts; i++) {
+    temp += dot_v3v3(fLongVectorA[i], fLongVectorB[i]);
+  }
+  return temp;
 }
 /* A = B + C  --> for big vector */
-DO_INLINE void add_lfvector_lfvector(float(*to)[3], float(*fLongVectorA)[3], float(*fLongVectorB)[3], unsigned int verts)
+DO_INLINE void add_lfvector_lfvector(float (*to)[3],
+                                     float (*fLongVectorA)[3],
+                                     float (*fLongVectorB)[3],
+                                     unsigned int verts)
 {
-	unsigned int i = 0;
-
-	for (i = 0; i < verts; i++) {
-		add_v3_v3v3(to[i], fLongVectorA[i], fLongVectorB[i]);
-	}
+  unsigned int i = 0;
 
+  for (i = 0; i < verts; i++) {
+    add_v3_v3v3(to[i], fLongVectorA[i], fLongVectorB[i]);
+  }
 }
 /* A = B + C * float --> for big vector */
-DO_INLINE void add_lfvector_lfvectorS(float(*to)[3], float(*fLongVectorA)[3], float(*fLongVectorB)[3], float bS, unsigned int verts)
+DO_INLINE void add_lfvector_lfvectorS(float (*to)[3],
+                                      float (*fLongVectorA)[3],
+                                      float (*fLongVectorB)[3],
+                                      float bS,
+                                      unsigned int verts)
 {
-	unsigned int i = 0;
-
-	for (i = 0; i < verts; i++) {
-		VECADDS(to[i], fLongVectorA[i], fLongVectorB[i], bS);
+  unsigned int i = 0;
 
-	}
+  for (i = 0; i < verts; i++) {
+    VECADDS(to[i], fLongVectorA[i], fLongVectorB[i], bS);
+  }
 }
 /* A = B * float + C * float --> for big vector */
-DO_INLINE void add_lfvectorS_lfvectorS(float(*to)[3], float(*fLongVectorA)[3], float aS, float(*fLongVectorB)[3], float bS, unsigned int verts)
+DO_INLINE void add_lfvectorS_lfvectorS(float (*to)[3],
+                                       float (*fLongVectorA)[3],
+                                       float aS,
+                                       float (*fLongVectorB)[3],
+                                       float bS,
+                                       unsigned int verts)
 {
-	unsigned int i = 0;
+  unsigned int i = 0;
 
-	for (i = 0; i < verts; i++) {
-		VECADDSS(to[i], fLongVectorA[i], aS, fLongVectorB[i], bS);
-	}
+  for (i = 0; i < verts; i++) {
+    VECADDSS(to[i], fLongVectorA[i], aS, fLongVectorB[i], bS);
+  }
 }
 /* A = B - C * float --> for big vector */
-DO_INLINE void sub_lfvector_lfvectorS(float(*to)[3], float(*fLongVectorA)[3], float(*fLongVectorB)[3], float bS, unsigned int verts)
+DO_INLINE void sub_lfvector_lfvectorS(float (*to)[3],
+                                      float (*fLongVectorA)[3],
+                                      float (*fLongVectorB)[3],
+                                      float bS,
+                                      unsigned int verts)
 {
-	unsigned int i = 0;
-	for (i = 0; i < verts; i++) {
-		VECSUBS(to[i], fLongVectorA[i], fLongVectorB[i], bS);
-	}
-
+  unsigned int i = 0;
+  for (i = 0; i < verts; i++) {
+    VECSUBS(to[i], fLongVectorA[i], fLongVectorB[i], bS);
+  }
 }
 /* A = B - C --> for big vector */
-DO_INLINE void sub_lfvector_lfvector(float(*to)[3], float(*fLongVectorA)[3], float(*fLongVectorB)[3], unsigned int verts)
+DO_INLINE void sub_lfvector_lfvector(float (*to)[3],
+                                     float (*fLongVectorA)[3],
+                                     float (*fLongVectorB)[3],
+                                     unsigned int verts)
 {
-	unsigned int i = 0;
-
-	for (i = 0; i < verts; i++) {
-		sub_v3_v3v3(to[i], fLongVectorA[i], fLongVectorB[i]);
-	}
+  unsigned int i = 0;
 
+  for (i = 0; i < verts; i++) {
+    sub_v3_v3v3(to[i], fLongVectorA[i], fLongVectorB[i]);
+  }
 }
 ///////////////////////////
 // 3x3 matrix
 ///////////////////////////
-#if 0
+#  if 0
 /* printf 3x3 matrix on console: for debug output */
 static void print_fmatrix(float m3[3][3])
 {
-	printf("%f\t%f\t%f\n", m3[0][0], m3[0][1], m3[0][2]);
-	printf("%f\t%f\t%f\n", m3[1][0], m3[1][1], m3[1][2]);
-	printf("%f\t%f\t%f\n\n", m3[2][0], m3[2][1], m3[2][2]);
+  printf("%f\t%f\t%f\n", m3[0][0], m3[0][1], m3[0][2]);
+  printf("%f\t%f\t%f\n", m3[1][0], m3[1][1], m3[1][2]);
+  printf("%f\t%f\t%f\n\n", m3[2][0], m3[2][1], m3[2][2]);
 }
 
 static void print_sparse_matrix(fmatrix3x3 *m)
 {
-	if (m) {
-		unsigned int i;
-		for (i = 0; i < m[0].vcount + m[0].scount; i++) {
-			printf("%d:\n", i);
-			print_fmatrix(m[i].m);
-		}
-	}
+  if (m) {
+    unsigned int i;
+    for (i = 0; i < m[0].vcount + m[0].scount; i++) {
+      printf("%d:\n", i);
+      print_fmatrix(m[i].m);
+    }
+  }
 }
-#endif
+#  endif
 
-#if 0
+#  if 0
 static void print_lvector(lfVector *v, int numverts)
 {
-	int i;
-	for (i = 0; i < numverts; ++i) {
-		if (i > 0)
-			printf("\n");
+  int i;
+  for (i = 0; i < numverts; ++i) {
+    if (i > 0)
+      printf("\n");
 
-		printf("%f,\n", v[i][0]);
-		printf("%f,\n", v[i][1]);
-		printf("%f,\n", v[i][2]);
-	}
+    printf("%f,\n", v[i][0]);
+    printf("%f,\n", v[i][1]);
+    printf("%f,\n", v[i][2]);
+  }
 }
-#endif
+#  endif
 
-#if 0
+#  if 0
 static void print_bfmatrix(fmatrix3x3 *m)
 {
-	int tot = m[0].vcount + m[0].scount;
-	int size = m[0].vcount * 3;
-	float *t = MEM_callocN(sizeof(float) * size * size, "bfmatrix");
-	int q, i, j;
-
-	for (q = 0; q < tot; ++q) {
-		int k = 3 * m[q].r;
-		int l = 3 * m[q].c;
-
-		for (j = 0; j < 3; ++j) {
-			for (i = 0; i < 3; ++i) {
-//				if (t[k + i + (l + j) * size] != 0.0f) {
-//					printf("warning: overwriting value at %d, %d\n", m[q].r, m[q].c);
-//				}
-				if (k == l) {
-					t[k + i + (k + j) * size] += m[q].m[i][j];
-				}
-				else {
-					t[k + i + (l + j) * size] += m[q].m[i][j];
-					t[l + j + (k + i) * size] += m[q].m[j][i];
-				}
-			}
-		}
-	}
-
-	for (j = 0; j < size; ++j) {
-		if (j > 0 && j % 3 == 0)
-			printf("\n");
-
-		for (i = 0; i < size; ++i) {
-			if (i > 0 && i % 3 == 0)
-				printf("  ");
-
-			implicit_print_matrix_elem(t[i + j * size]);
-		}
-		printf("\n");
-	}
-
-	MEM_freeN(t);
-}
-#endif
+  int tot = m[0].vcount + m[0].scount;
+  int size = m[0].vcount * 3;
+  float *t = MEM_callocN(sizeof(float) * size * size, "bfmatrix");
+  int q, i, j;
+
+  for (q = 0; q < tot; ++q) {
+    int k = 3 * m[q].r;
+    int l = 3 * m[q].c;
+
+    for (j = 0; j < 3; ++j) {
+      for (i = 0; i < 3; ++i) {
+//              if (t[k + i + (l + j) * size] != 0.0f) {
+//                  printf("warning: overwriting value at %d, %d\n", m[q].r, m[q].c);
+//              }
+        if (k == l) {
+          t[k + i + (k + j) * size] += m[q].m[i][j];
+        }
+        else {
+          t[k + i + (l + j) * size] += m[q].m[i][j];
+          t[l + j + (k + i) * size] += m[q].m[j][i];
+        }
+      }
+    }
+  }
+
+  for (j = 0; j < size; ++j) {
+    if (j > 0 && j % 3 == 0)
+      printf("\n");
+
+    for (i = 0; i < size; ++i) {
+      if (i > 0 && i % 3 == 0)
+        printf("  ");
+
+      implicit_print_matrix_elem(t[i + j * size]);
+    }
+    printf("\n");
+  }
+
+  MEM_freeN(t);
+}
+#  endif
 
 /* copy 3x3 matrix */
 DO_INLINE void cp_fmatrix(float to[3][3], float from[3][3])
 {
-	// memcpy(to, from, sizeof (float) * 9);
-	copy_v3_v3(to[0], from[0]);
-	copy_v3_v3(to[1], from[1]);
-	copy_v3_v3(to[2], from[2]);
+  // memcpy(to, from, sizeof (float) * 9);
+  copy_v3_v3(to[0], from[0]);
+  copy_v3_v3(to[1], from[1]);
+  copy_v3_v3(to[2], from[2]);
 }
 
 /* copy 3x3 matrix */
 DO_INLINE void initdiag_fmatrixS(float to[3][3], float aS)
 {
-	cp_fmatrix(to, ZERO);
+  cp_fmatrix(to, ZERO);
 
-	to[0][0] = aS;
-	to[1][1] = aS;
-	to[2][2] = aS;
+  to[0][0] = aS;
+  to[1][1] = aS;
+  to[2][2] = aS;
 }
 
-#if 0
+#  if 0
 /* calculate determinant of 3x3 matrix */
 DO_INLINE float det_fmatrix(float m[3][3])
 {
-	return m[0][0] * m[1][1] * m[2][2] + m[1][0] * m[2][1] * m[0][2] + m[0][1] * m[1][2] * m[2][0] -
-	       m[0][0] * m[1][2] * m[2][1] - m[0][1] * m[1][0] * m[2][2] - m[2][0] * m[1][1] * m[0][2];
+  return m[0][0] * m[1][1] * m[2][2] + m[1][0] * m[2][1] * m[0][2] + m[0][1] * m[1][2] * m[2][0] -
+         m[0][0] * m[1][2] * m[2][1] - m[0][1] * m[1][0] * m[2][2] - m[2][0] * m[1][1] * m[0][2];
 }
 
 DO_INLINE void inverse_fmatrix(float to[3][3], float from[3][3])
 {
-	unsigned int i, j;
-	float d;
-
-	if ((d = det_fmatrix(from)) == 0) {
-		printf("can't build inverse");
-		exit(0);
-	}
-	for (i = 0; i < 3; i++) {
-		for (j = 0; j < 3; j++) {
-			int i1 = (i + 1) % 3;
-			int i2 = (i + 2) % 3;
-			int j1 = (j + 1) % 3;
-			int j2 = (j + 2) % 3;
-			/** Reverse indexes i&j to take transpose. */
-			to[j][i] = (from[i1][j1] * from[i2][j2] - from[i1][j2] * from[i2][j1]) / d;
-			/**
-			 * <pre>
-			 * if (i == j) {
-			 *     to[i][j] = 1.0f / from[i][j];
-			 * }
-			 * else {
-			 *     to[i][j] = 0;
-			 * }
-			 * </pre>
-			 */
-		}
-	}
-
-}
-#endif
+  unsigned int i, j;
+  float d;
+
+  if ((d = det_fmatrix(from)) == 0) {
+    printf("can't build inverse");
+    exit(0);
+  }
+  for (i = 0; i < 3; i++) {
+    for (j = 0; j < 3; j++) {
+      int i1 = (i + 1) % 3;
+      int i2 = (i + 2) % 3;
+      int j1 = (j + 1) % 3;
+      int j2 = (j + 2) % 3;
+      /** Reverse indexes i&j to take transpose. */
+      to[j][i] = (from[i1][j1] * from[i2][j2] - from[i1][j2] * from[i2][j1]) / d;
+      /**
+       * <pre>
+       * if (i == j) {
+       *     to[i][j] = 1.0f / from[i][j];
+       * }
+       * else {
+       *     to[i][j] = 0;
+       * }
+       * </pre>
+       */
+    }
+  }
+
+}
+#  endif
 
 /* 3x3 matrix multiplied by a scalar */
 /* STATUS: verified */
 DO_INLINE void mul_fmatrix_S(float matrix[3][3], float scalar)
 {
-	mul_fvector_S(matrix[0], matrix[0], scalar);
-	mul_fvector_S(matrix[1], matrix[1], scalar);
-	mul_fvector_S(matrix[2], matrix[2], scalar);
+  mul_fvector_S(matrix[0], matrix[0], scalar);
+  mul_fvector_S(matrix[1], matrix[1], scalar);
+  mul_fvector_S(matrix[2], matrix[2], scalar);
 }
 
 /* a vector multiplied by a 3x3 matrix */
 /* STATUS: verified */
 DO_INLINE void mul_fvector_fmatrix(float *to, float *from, float matrix[3][3])
 {
-	to[0] = matrix[0][0] * from[0] + matrix[1][0] * from[1] + matrix[2][0] * from[2];
-	to[1] = matrix[0][1] * from[0] + matrix[1][1] * from[1] + matrix[2][1] * from[2];
-	to[2] = matrix[0][2] * from[0] + matrix[1][2] * from[1] + matrix[2][2] * from[2];
+  to[0] = matrix[0][0] * from[0] + matrix[1][0] * from[1] + matrix[2][0] * from[2];
+  to[1] = matrix[0][1] * from[0] + matrix[1][1] * from[1] + matrix[2][1] * from[2];
+  to[2] = matrix[0][2] * from[0] + matrix[1][2] * from[1] + matrix[2][2] * from[2];
 }
 
 /* 3x3 matrix multiplied by a vector */
 /* STATUS: verified */
 DO_INLINE void mul_fmatrix_fvector(float *to, float matrix[3][3], float from[3])
 {
-	to[0] = dot_v3v3(matrix[0], from);
-	to[1] = dot_v3v3(matrix[1], from);
-	to[2] = dot_v3v3(matrix[2], from);
+  to[0] = dot_v3v3(matrix[0], from);
+  to[1] = dot_v3v3(matrix[1], from);
+  to[2] = dot_v3v3(matrix[2], from);
 }
 /* 3x3 matrix addition with 3x3 matrix */
 DO_INLINE void add_fmatrix_fmatrix(float to[3][3], float matrixA[3][3], float matrixB[3][3])
 {
-	add_v3_v3v3(to[0], matrixA[0], matrixB[0]);
-	add_v3_v3v3(to[1], matrixA[1], matrixB[1]);
-	add_v3_v3v3(to[2], matrixA[2], matrixB[2]);
+  add_v3_v3v3(to[0], matrixA[0], matrixB[0]);
+  add_v3_v3v3(to[1], matrixA[1], matrixB[1]);
+  add_v3_v3v3(to[2], matrixA[2], matrixB[2]);
 }
 /* A -= B*x + C*y (3x3 matrix sub-addition with 3x3 matrix) */
-DO_INLINE void subadd_fmatrixS_fmatrixS(float to[3][3], float matrixA[3][3], float aS, float matrixB[3][3], float bS)
+DO_INLINE void subadd_fmatrixS_fmatrixS(
+    float to[3][3], float matrixA[3][3], float aS, float matrixB[3][3], float bS)
 {
-	VECSUBADDSS(to[0], matrixA[0], aS, matrixB[0], bS);
-	VECSUBADDSS(to[1], matrixA[1], aS, matrixB[1], bS);
-	VECSUBADDSS(to[2], matrixA[2], aS, matrixB[2], bS);
+  VECSUBADDSS(to[0], matrixA[0], aS, matrixB[0], bS);
+  VECSUBADDSS(to[1], matrixA[1], aS, matrixB[1], bS);
+  VECSUBADDSS(to[2], matrixA[2], aS, matrixB[2], bS);
 }
 /* A = B - C (3x3 matrix subtraction with 3x3 matrix) */
 DO_INLINE void sub_fmatrix_fmatrix(float to[3][3], float matrixA[3][3], float matrixB[3][3])
 {
-	sub_v3_v3v3(to[0], matrixA[0], matrixB[0]);
-	sub_v3_v3v3(to[1], matrixA[1], matrixB[1]);
-	sub_v3_v3v3(to[2], matrixA[2], matrixB[2]);
+  sub_v3_v3v3(to[0], matrixA[0], matrixB[0]);
+  sub_v3_v3v3(to[1], matrixA[1], matrixB[1]);
+  sub_v3_v3v3(to[2], matrixA[2], matrixB[2]);
 }
 /////////////////////////////////////////////////////////////////
 // special functions
@@ -447,50 +471,56 @@ DO_INLINE void sub_fmatrix_fmatrix(float to[3][3], float matrixA[3][3], float ma
 /* STATUS: verified */
 DO_INLINE void muladd_fmatrix_fvector(float to[3], float matrix[3][3], float from[3])
 {
-	to[0] += dot_v3v3(matrix[0], from);
-	to[1] += dot_v3v3(matrix[1], from);
-	to[2] += dot_v3v3(matrix[2], from);
+  to[0] += dot_v3v3(matrix[0], from);
+  to[1] += dot_v3v3(matrix[1], from);
+  to[2] += dot_v3v3(matrix[2], from);
 }
 
 DO_INLINE void muladd_fmatrixT_fvector(float to[3], float matrix[3][3], float from[3])
 {
-	to[0] += matrix[0][0] * from[0] + matrix[1][0] * from[1] + matrix[2][0] * from[2];
-	to[1] += matrix[0][1] * from[0] + matrix[1][1] * from[1] + matrix[2][1] * from[2];
-	to[2] += matrix[0][2] * from[0] + matrix[1][2] * from[1] + matrix[2][2] * from[2];
+  to[0] += matrix[0][0] * from[0] + matrix[1][0] * from[1] + matrix[2][0] * from[2];
+  to[1] += matrix[0][1] * from[0] + matrix[1][1] * from[1] + matrix[2][1] * from[2];
+  to[2] += matrix[0][2] * from[0] + matrix[1][2] * from[1] + matrix[2][2] * from[2];
 }
 
 BLI_INLINE void outerproduct(float r[3][3], const float a[3], const float b[3])
 {
-	mul_v3_v3fl(r[0], a, b[0]);
-	mul_v3_v3fl(r[1], a, b[1]);
-	mul_v3_v3fl(r[2], a, b[2]);
+  mul_v3_v3fl(r[0], a, b[0]);
+  mul_v3_v3fl(r[1], a, b[1]);
+  mul_v3_v3fl(r[2], a, b[2]);
 }
 
 BLI_INLINE void cross_m3_v3m3(float r[3][3], const float v[3], float m[3][3])
 {
-	cross_v3_v3v3(r[0], v, m[0]);
-	cross_v3_v3v3(r[1], v, m[1]);
-	cross_v3_v3v3(r[2], v, m[2]);
+  cross_v3_v3v3(r[0], v, m[0]);
+  cross_v3_v3v3(r[1], v, m[1]);
+  cross_v3_v3v3(r[2], v, m[2]);
 }
 
 BLI_INLINE void cross_v3_identity(float r[3][3], const float v[3])
 {
-	r[0][0] = 0.0f;     r[1][0] = v[2];     r[2][0] = -v[1];
-	r[0][1] = -v[2];    r[1][1] = 0.0f;     r[2][1] = v[0];
-	r[0][2] = v[1];     r[1][2] = -v[0];    r[2][2] = 0.0f;
+  r[0][0] = 0.0f;
+  r[1][0] = v[2];
+  r[2][0] = -v[1];
+  r[0][1] = -v[2];
+  r[1][1] = 0.0f;
+  r[2][1] = v[0];
+  r[0][2] = v[1];
+  r[1][2] = -v[0];
+  r[2][2] = 0.0f;
 }
 
 BLI_INLINE void madd_m3_m3fl(float r[3][3], float m[3][3], float f)
 {
-	r[0][0] += m[0][0] * f;
-	r[0][1] += m[0][1] * f;
-	r[0][2] += m[0][2] * f;
-	r[1][0] += m[1][0] * f;
-	r[1][1] += m[1][1] * f;
-	r[1][2] += m[1][2] * f;
-	r[2][0] += m[2][0] * f;
-	r[2][1] += m[2][1] * f;
-	r[2][2] += m[2][2] * f;
+  r[0][0] += m[0][0] * f;
+  r[0][1] += m[0][1] * f;
+  r[0][2] += m[0][2] * f;
+  r[1][0] += m[1][0] * f;
+  r[1][1] += m[1][1] * f;
+  r[1][2] += m[1][2] * f;
+  r[2][0] += m[2][0] * f;
+  r[2][1] += m[2][1] * f;
+  r[2][2] += m[2][2] * f;
 }
 
 /////////////////////////////////////////////////////////////////
@@ -499,126 +529,127 @@ BLI_INLINE void madd_m3_m3fl(float r[3][3], float m[3][3], float f)
 // SPARSE SYMMETRIC big matrix with 3x3 matrix entries
 ///////////////////////////
 /* printf a big matrix on console: for debug output */
-#if 0
+#  if 0
 static void print_bfmatrix(fmatrix3x3 *m3)
 {
-	unsigned int i = 0;
+  unsigned int i = 0;
 
-	for (i = 0; i < m3[0].vcount + m3[0].scount; i++)
-	{
-		print_fmatrix(m3[i].m);
-	}
+  for (i = 0; i < m3[0].vcount + m3[0].scount; i++)
+  {
+    print_fmatrix(m3[i].m);
+  }
 }
-#endif
+#  endif
 
 BLI_INLINE void init_fmatrix(fmatrix3x3 *matrix, int r, int c)
 {
-	matrix->r = r;
-	matrix->c = c;
+  matrix->r = r;
+  matrix->c = c;
 }
 
 /* create big matrix */
 DO_INLINE fmatrix3x3 *create_bfmatrix(unsigned int verts, unsigned int springs)
 {
-	// TODO: check if memory allocation was successful */
-	fmatrix3x3 *temp = (fmatrix3x3 *)MEM_callocN(sizeof(fmatrix3x3) * (verts + springs), "cloth_implicit_alloc_matrix");
-	int i;
+  // TODO: check if memory allocation was successful */
+  fmatrix3x3 *temp = (fmatrix3x3 *)MEM_callocN(sizeof(fmatrix3x3) * (verts + springs),
+                                               "cloth_implicit_alloc_matrix");
+  int i;
 
-	temp[0].vcount = verts;
-	temp[0].scount = springs;
+  temp[0].vcount = verts;
+  temp[0].scount = springs;
 
-	/* vertex part of the matrix is diagonal blocks */
-	for (i = 0; i < verts; ++i) {
-		init_fmatrix(temp + i, i, i);
-	}
+  /* vertex part of the matrix is diagonal blocks */
+  for (i = 0; i < verts; ++i) {
+    init_fmatrix(temp + i, i, i);
+  }
 
-	return temp;
+  return temp;
 }
 /* delete big matrix */
 DO_INLINE void del_bfmatrix(fmatrix3x3 *matrix)
 {
-	if (matrix != NULL) {
-		MEM_freeN(matrix);
-	}
+  if (matrix != NULL) {
+    MEM_freeN(matrix);
+  }
 }
 
 /* copy big matrix */
 DO_INLINE void cp_bfmatrix(fmatrix3x3 *to, fmatrix3x3 *from)
 {
-	// TODO bounds checking
-	memcpy(to, from, sizeof(fmatrix3x3) * (from[0].vcount + from[0].scount));
+  // TODO bounds checking
+  memcpy(to, from, sizeof(fmatrix3x3) * (from[0].vcount + from[0].scount));
 }
 
 /* init big matrix */
 // slow in parallel
 DO_INLINE void init_bfmatrix(fmatrix3x3 *matrix, float m3[3][3])
 {
-	unsigned int i;
+  unsigned int i;
 
-	for (i = 0; i < matrix[0].vcount + matrix[0].scount; i++) {
-		cp_fmatrix(matrix[i].m, m3);
-	}
+  for (i = 0; i < matrix[0].vcount + matrix[0].scount; i++) {
+    cp_fmatrix(matrix[i].m, m3);
+  }
 }
 
 /* init the diagonal of big matrix */
 // slow in parallel
 DO_INLINE void initdiag_bfmatrix(fmatrix3x3 *matrix, float m3[3][3])
 {
-	unsigned int i, j;
-	float tmatrix[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};
+  unsigned int i, j;
+  float tmatrix[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};
 
-	for (i = 0; i < matrix[0].vcount; i++) {
-		cp_fmatrix(matrix[i].m, m3);
-	}
-	for (j = matrix[0].vcount; j < matrix[0].vcount + matrix[0].scount; j++) {
-		cp_fmatrix(matrix[j].m, tmatrix);
-	}
+  for (i = 0; i < matrix[0].vcount; i++) {
+    cp_fmatrix(matrix[i].m, m3);
+  }
+  for (j = matrix[0].vcount; j < matrix[0].vcount + matrix[0].scount; j++) {
+    cp_fmatrix(matrix[j].m, tmatrix);
+  }
 }
 
 /* SPARSE SYMMETRIC multiply big matrix with long vector*/
 /* STATUS: verified */
-DO_INLINE void mul_bfmatrix_lfvector(float(*to)[3], fmatrix3x3 *from, lfVector *fLongVector)
-{
-	unsigned int i = 0;
-	unsigned int vcount = from[0].vcount;
-	lfVector *temp = create_lfvector(vcount);
-
-	zero_lfvector(to, vcount);
-
-#pragma omp parallel sections private(i) if (vcount > CLOTH_OPENMP_LIMIT)
-	{
-#pragma omp section
-		{
-			for (i = from[0].vcount; i < from[0].vcount + from[0].scount; i++) {
-				/* This is the lower triangle of the sparse matrix,
-				 * therefore multiplication occurs with transposed submatrices. */
-				muladd_fmatrixT_fvector(to[from[i].c], from[i].m, fLongVector[from[i].r]);
-			}
-		}
-#pragma omp section
-		{
-			for (i = 0; i < from[0].vcount + from[0].scount; i++) {
-				muladd_fmatrix_fvector(temp[from[i].r], from[i].m, fLongVector[from[i].c]);
-			}
-		}
-	}
-	add_lfvector_lfvector(to, to, temp, from[0].vcount);
-
-	del_lfvector(temp);
+DO_INLINE void mul_bfmatrix_lfvector(float (*to)[3], fmatrix3x3 *from, lfVector *fLongVector)
+{
+  unsigned int i = 0;
+  unsigned int vcount = from[0].vcount;
+  lfVector *temp = create_lfvector(vcount);
+
+  zero_lfvector(to, vcount);
+
+#  pragma omp parallel sections private(i) if (vcount > CLOTH_OPENMP_LIMIT)
+  {
+#  pragma omp section
+    {
+      for (i = from[0].vcount; i < from[0].vcount + from[0].scount; i++) {
+        /* This is the lower triangle of the sparse matrix,
+         * therefore multiplication occurs with transposed submatrices. */
+        muladd_fmatrixT_fvector(to[from[i].c], from[i].m, fLongVector[from[i].r]);
+      }
+    }
+#  pragma omp section
+    {
+      for (i = 0; i < from[0].vcount + from[0].scount; i++) {
+        muladd_fmatrix_fvector(temp[from[i].r], from[i].m, fLongVector[from[i].c]);
+      }
+    }
+  }
+  add_lfvector_lfvector(to, to, temp, from[0].vcount);
+
+  del_lfvector(temp);
 }
 
 /* SPARSE SYMMETRIC sub big matrix with big matrix*/
 /* A -= B * float + C * float --> for big matrix */
 /* VERIFIED */
-DO_INLINE void subadd_bfmatrixS_bfmatrixS(fmatrix3x3 *to, fmatrix3x3 *from, float aS,  fmatrix3x3 *matrix, float bS)
+DO_INLINE void subadd_bfmatrixS_bfmatrixS(
+    fmatrix3x3 *to, fmatrix3x3 *from, float aS, fmatrix3x3 *matrix, float bS)
 {
-	unsigned int i = 0;
-
-	/* process diagonal elements */
-	for (i = 0; i < matrix[0].vcount + matrix[0].scount; i++) {
-		subadd_fmatrixS_fmatrixS(to[i].m, from[i].m, aS, matrix[i].m, bS);
-	}
+  unsigned int i = 0;
 
+  /* process diagonal elements */
+  for (i = 0; i < matrix[0].vcount + matrix[0].scount; i++) {
+    subadd_fmatrixS_fmatrixS(to[i].m, from[i].m, aS, matrix[i].m, bS);
+  }
 }
 
 ///////////////////////////////////////////////////////////////////
@@ -626,1136 +657,1211 @@ DO_INLINE void subadd_bfmatrixS_bfmatrixS(fmatrix3x3 *to, fmatrix3x3 *from, floa
 ///////////////////////////////////////////////////////////////////
 
 typedef struct Implicit_Data {
-	/* inputs */
-	fmatrix3x3 *bigI;           /* identity (constant) */
-	fmatrix3x3 *tfm;            /* local coordinate transform */
-	fmatrix3x3 *M;              /* masses */
-	lfVector *F;                /* forces */
-	fmatrix3x3 *dFdV, *dFdX;    /* force jacobians */
-	int num_blocks;             /* number of off-diagonal blocks (springs) */
-
-	/* motion state data */
-	lfVector *X, *Xnew;         /* positions */
-	lfVector *V, *Vnew;         /* velocities */
-
-	/* internal solver data */
-	lfVector *B;                /* B for A*dV = B */
-	fmatrix3x3 *A;              /* A for A*dV = B */
-
-	lfVector *dV;               /* velocity change (solution of A*dV = B) */
-	lfVector *z;                /* target velocity in constrained directions */
-	fmatrix3x3 *S;              /* filtering matrix for constraints */
-	fmatrix3x3 *P, *Pinv;       /* pre-conditioning matrix */
+  /* inputs */
+  fmatrix3x3 *bigI;        /* identity (constant) */
+  fmatrix3x3 *tfm;         /* local coordinate transform */
+  fmatrix3x3 *M;           /* masses */
+  lfVector *F;             /* forces */
+  fmatrix3x3 *dFdV, *dFdX; /* force jacobians */
+  int num_blocks;          /* number of off-diagonal blocks (springs) */
+
+  /* motion state data */
+  lfVector *X, *Xnew; /* positions */
+  lfVector *V, *Vnew; /* velocities */
+
+  /* internal solver data */
+  lfVector *B;   /* B for A*dV = B */
+  fmatrix3x3 *A; /* A for A*dV = B */
+
+  lfVector *dV;         /* velocity change (solution of A*dV = B) */
+  lfVector *z;          /* target velocity in constrained directions */
+  fmatrix3x3 *S;        /* filtering matrix for constraints */
+  fmatrix3x3 *P, *Pinv; /* pre-conditioning matrix */
 } Implicit_Data;
 
 Implicit_Data *BPH_mass_spring_solver_create(int numverts, int numsprings)
 {
-	Implicit_Data *id = (Implicit_Data *)MEM_callocN(sizeof(Implicit_Data), "implicit vecmat");
+  Implicit_Data *id = (Implicit_Data *)MEM_callocN(sizeof(Implicit_Data), "implicit vecmat");
 
-	/* process diagonal elements */
-	id->tfm = create_bfmatrix(numverts, 0);
-	id->A = create_bfmatrix(numverts, numsprings);
-	id->dFdV = create_bfmatrix(numverts, numsprings);
-	id->dFdX = create_bfmatrix(numverts, numsprings);
-	id->S = create_bfmatrix(numverts, 0);
-	id->Pinv = create_bfmatrix(numverts, numsprings);
-	id->P = create_bfmatrix(numverts, numsprings);
-	id->bigI = create_bfmatrix(numverts, numsprings); // TODO 0 springs
-	id->M = create_bfmatrix(numverts, numsprings);
-	id->X = create_lfvector(numverts);
-	id->Xnew = create_lfvector(numverts);
-	id->V = create_lfvector(numverts);
-	id->Vnew = create_lfvector(numverts);
-	id->F = create_lfvector(numverts);
-	id->B = create_lfvector(numverts);
-	id->dV = create_lfvector(numverts);
-	id->z = create_lfvector(numverts);
+  /* process diagonal elements */
+  id->tfm = create_bfmatrix(numverts, 0);
+  id->A = create_bfmatrix(numverts, numsprings);
+  id->dFdV = create_bfmatrix(numverts, numsprings);
+  id->dFdX = create_bfmatrix(numverts, numsprings);
+  id->S = create_bfmatrix(numverts, 0);
+  id->Pinv = create_bfmatrix(numverts, numsprings);
+  id->P = create_bfmatrix(numverts, numsprings);
+  id->bigI = create_bfmatrix(numverts, numsprings);  // TODO 0 springs
+  id->M = create_bfmatrix(numverts, numsprings);
+  id->X = create_lfvector(numverts);
+  id->Xnew = create_lfvector(numverts);
+  id->V = create_lfvector(numverts);
+  id->Vnew = create_lfvector(numverts);
+  id->F = create_lfvector(numverts);
+  id->B = create_lfvector(numverts);
+  id->dV = create_lfvector(numverts);
+  id->z = create_lfvector(numverts);
 
-	initdiag_bfmatrix(id->bigI, I);
+  initdiag_bfmatrix(id->bigI, I);
 
-	return id;
+  return id;
 }
 
 void BPH_mass_spring_solver_free(Implicit_Data *id)
 {
-	del_bfmatrix(id->tfm);
-	del_bfmatrix(id->A);
-	del_bfmatrix(id->dFdV);
-	del_bfmatrix(id->dFdX);
-	del_bfmatrix(id->S);
-	del_bfmatrix(id->P);
-	del_bfmatrix(id->Pinv);
-	del_bfmatrix(id->bigI);
-	del_bfmatrix(id->M);
+  del_bfmatrix(id->tfm);
+  del_bfmatrix(id->A);
+  del_bfmatrix(id->dFdV);
+  del_bfmatrix(id->dFdX);
+  del_bfmatrix(id->S);
+  del_bfmatrix(id->P);
+  del_bfmatrix(id->Pinv);
+  del_bfmatrix(id->bigI);
+  del_bfmatrix(id->M);
 
-	del_lfvector(id->X);
-	del_lfvector(id->Xnew);
-	del_lfvector(id->V);
-	del_lfvector(id->Vnew);
-	del_lfvector(id->F);
-	del_lfvector(id->B);
-	del_lfvector(id->dV);
-	del_lfvector(id->z);
+  del_lfvector(id->X);
+  del_lfvector(id->Xnew);
+  del_lfvector(id->V);
+  del_lfvector(id->Vnew);
+  del_lfvector(id->F);
+  del_lfvector(id->B);
+  del_lfvector(id->dV);
+  del_lfvector(id->z);
 
-	MEM_freeN(id);
+  MEM_freeN(id);
 }
 
 /* ==== Transformation from/to root reference frames ==== */
 
 BLI_INLINE void world_to_root_v3(Implicit_Data *data, int index, float r[3], const float v[3])
 {
-	copy_v3_v3(r, v);
-	mul_transposed_m3_v3(data->tfm[index].m, r);
+  copy_v3_v3(r, v);
+  mul_transposed_m3_v3(data->tfm[index].m, r);
 }
 
 BLI_INLINE void root_to_world_v3(Implicit_Data *data, int index, float r[3], const float v[3])
 {
-	mul_v3_m3v3(r, data->tfm[index].m, v);
+  mul_v3_m3v3(r, data->tfm[index].m, v);
 }
 
 BLI_INLINE void world_to_root_m3(Implicit_Data *data, int index, float r[3][3], float m[3][3])
 {
-	float trot[3][3];
-	copy_m3_m3(trot, data->tfm[index].m);
-	transpose_m3(trot);
-	mul_m3_m3m3(r, trot, m);
+  float trot[3][3];
+  copy_m3_m3(trot, data->tfm[index].m);
+  transpose_m3(trot);
+  mul_m3_m3m3(r, trot, m);
 }
 
 BLI_INLINE void root_to_world_m3(Implicit_Data *data, int index, float r[3][3], float m[3][3])
 {
-	mul_m3_m3m3(r, data->tfm[index].m, m);
+  mul_m3_m3m3(r, data->tfm[index].m, m);
 }
 
 /* ================================ */
 
 DO_INLINE void filter(lfVector *V, fmatrix3x3 *S)
 {
-	unsigned int i = 0;
+  unsigned int i = 0;
 
-	for (i = 0; i < S[0].vcount; i++) {
-		mul_m3_v3(S[i].m, V[S[i].r]);
-	}
+  for (i = 0; i < S[0].vcount; i++) {
+    mul_m3_v3(S[i].m, V[S[i].r]);
+  }
 }
 
-#if 0 /* this version of the CG algorithm does not work very well with partial constraints (where S has non-zero elements) */
+#  if 0 /* this version of the CG algorithm does not work very well with partial constraints (where S has non-zero elements) */
 static int  cg_filtered(lfVector *ldV, fmatrix3x3 *lA, lfVector *lB, lfVector *z, fmatrix3x3 *S)
 {
-	// Solves for unknown X in equation AX=B
-	unsigned int conjgrad_loopcount = 0, conjgrad_looplimit = 100;
-	float conjgrad_epsilon = 0.0001f /* , conjgrad_lasterror=0 */ /* UNUSED */;
-	lfVector *q, *d, *tmp, *r;
-	float s, starget, a, s_prev;
-	unsigned int numverts = lA[0].vcount;
-	q = create_lfvector(numverts);
-	d = create_lfvector(numverts);
-	tmp = create_lfvector(numverts);
-	r = create_lfvector(numverts);
+  // Solves for unknown X in equation AX=B
+  unsigned int conjgrad_loopcount = 0, conjgrad_looplimit = 100;
+  float conjgrad_epsilon = 0.0001f /* , conjgrad_lasterror=0 */ /* UNUSED */;
+  lfVector *q, *d, *tmp, *r;
+  float s, starget, a, s_prev;
+  unsigned int numverts = lA[0].vcount;
+  q = create_lfvector(numverts);
+  d = create_lfvector(numverts);
+  tmp = create_lfvector(numverts);
+  r = create_lfvector(numverts);
 
-	// zero_lfvector(ldV, CLOTHPARTICLES);
-	filter(ldV, S);
+  // zero_lfvector(ldV, CLOTHPARTICLES);
+  filter(ldV, S);
 
-	add_lfvector_lfvector(ldV, ldV, z, numverts);
+  add_lfvector_lfvector(ldV, ldV, z, numverts);
 
-	// r = B - Mul(tmp, A, X);    // just use B if X known to be zero
-	cp_lfvector(r, lB, numverts);
-	mul_bfmatrix_lfvector(tmp, lA, ldV);
-	sub_lfvector_lfvector(r, r, tmp, numverts);
+  // r = B - Mul(tmp, A, X);    // just use B if X known to be zero
+  cp_lfvector(r, lB, numverts);
+  mul_bfmatrix_lfvector(tmp, lA, ldV);
+  sub_lfvector_lfvector(r, r, tmp, numverts);
 
-	filter(r, S);
+  filter(r, S);
 
-	cp_lfvector(d, r, numverts);
+  cp_lfvector(d, r, numverts);
 
-	s = dot_lfvector(r, r, numverts);
-	starget = s * sqrtf(conjgrad_epsilon);
+  s = dot_lfvector(r, r, numverts);
+  starget = s * sqrtf(conjgrad_epsilon);
 
-	while (s > starget && conjgrad_loopcount < conjgrad_looplimit) {
-		// Mul(q, A, d); // q = A*d;
-		mul_bfmatrix_lfvector(q, lA, d);
+  while (s > starget && conjgrad_loopcount < conjgrad_looplimit) {
+    // Mul(q, A, d); // q = A*d;
+    mul_bfmatrix_lfvector(q, lA, d);
 
-		filter(q, S);
+    filter(q, S);
 
-		a = s / dot_lfvector(d, q, numverts);
+    a = s / dot_lfvector(d, q, numverts);
 
-		// X = X + d*a;
-		add_lfvector_lfvectorS(ldV, ldV, d, a, numverts);
+    // X = X + d*a;
+    add_lfvector_lfvectorS(ldV, ldV, d, a, numverts);
 
-		// r = r - q*a;
-		sub_lfvector_lfvectorS(r, r, q, a, numverts);
+    // r = r - q*a;
+    sub_lfvector_lfvectorS(r, r, q, a, numverts);
 
-		s_prev = s;
-		s = dot_lfvector(r, r, numverts);
+    s_prev = s;
+    s = dot_lfvector(r, r, numverts);
 
-		//d = r+d*(s/s_prev);
-		add_lfvector_lfvectorS(d, r, d, (s / s_prev), numverts);
+    //d = r+d*(s/s_prev);
+    add_lfvector_lfvectorS(d, r, d, (s / s_prev), numverts);
 
-		filter(d, S);
+    filter(d, S);
 
-		conjgrad_loopcount++;
-	}
-	/* conjgrad_lasterror = s; */ /* UNUSED */
+    conjgrad_loopcount++;
+  }
+  /* conjgrad_lasterror = s; */ /* UNUSED */
 
-	del_lfvector(q);
-	del_lfvector(d);
-	del_lfvector(tmp);
-	del_lfvector(r);
-	// printf("W/O conjgrad_loopcount: %d\n", conjgrad_loopcount);
+  del_lfvector(q);
+  del_lfvector(d);
+  del_lfvector(tmp);
+  del_lfvector(r);
+  // printf("W/O conjgrad_loopcount: %d\n", conjgrad_loopcount);
 
-	return conjgrad_loopcount < conjgrad_looplimit;  // true means we reached desired accuracy in given time - ie stable
+  return conjgrad_loopcount < conjgrad_looplimit;  // true means we reached desired accuracy in given time - ie stable
 }
-#endif
+#  endif
 
-static int cg_filtered(lfVector *ldV, fmatrix3x3 *lA, lfVector *lB, lfVector *z, fmatrix3x3 *S, ImplicitSolverResult *result)
+static int cg_filtered(lfVector *ldV,
+                       fmatrix3x3 *lA,
+                       lfVector *lB,
+                       lfVector *z,
+                       fmatrix3x3 *S,
+                       ImplicitSolverResult *result)
 {
-	// Solves for unknown X in equation AX=B
-	unsigned int conjgrad_loopcount = 0, conjgrad_looplimit = 100;
-	float conjgrad_epsilon = 0.01f;
+  // Solves for unknown X in equation AX=B
+  unsigned int conjgrad_loopcount = 0, conjgrad_looplimit = 100;
+  float conjgrad_epsilon = 0.01f;
 
-	unsigned int numverts = lA[0].vcount;
-	lfVector *fB = create_lfvector(numverts);
-	lfVector *AdV = create_lfvector(numverts);
-	lfVector *r = create_lfvector(numverts);
-	lfVector *c = create_lfvector(numverts);
-	lfVector *q = create_lfvector(numverts);
-	lfVector *s = create_lfvector(numverts);
-	float bnorm2, delta_new, delta_old, delta_target, alpha;
+  unsigned int numverts = lA[0].vcount;
+  lfVector *fB = create_lfvector(numverts);
+  lfVector *AdV = create_lfvector(numverts);
+  lfVector *r = create_lfvector(numverts);
+  lfVector *c = create_lfvector(numverts);
+  lfVector *q = create_lfvector(numverts);
+  lfVector *s = create_lfvector(numverts);
+  float bnorm2, delta_new, delta_old, delta_target, alpha;
 
-	cp_lfvector(ldV, z, numverts);
+  cp_lfvector(ldV, z, numverts);
 
-	/* d0 = filter(B)^T * P * filter(B) */
-	cp_lfvector(fB, lB, numverts);
-	filter(fB, S);
-	bnorm2 = dot_lfvector(fB, fB, numverts);
-	delta_target = conjgrad_epsilon * conjgrad_epsilon * bnorm2;
+  /* d0 = filter(B)^T * P * filter(B) */
+  cp_lfvector(fB, lB, numverts);
+  filter(fB, S);
+  bnorm2 = dot_lfvector(fB, fB, numverts);
+  delta_target = conjgrad_epsilon * conjgrad_epsilon * bnorm2;
 
-	/* r = filter(B - A * dV) */
-	mul_bfmatrix_lfvector(AdV, lA, ldV);
-	sub_lfvector_lfvector(r, lB, AdV, numverts);
-	filter(r, S);
+  /* r = filter(B - A * dV) */
+  mul_bfmatrix_lfvector(AdV, lA, ldV);
+  sub_lfvector_lfvector(r, lB, AdV, numverts);
+  filter(r, S);
 
-	/* c = filter(P^-1 * r) */
-	cp_lfvector(c, r, numverts);
-	filter(c, S);
+  /* c = filter(P^-1 * r) */
+  cp_lfvector(c, r, numverts);
+  filter(c, S);
 
-	/* delta = r^T * c */
-	delta_new = dot_lfvector(r, c, numverts);
+  /* delta = r^T * c */
+  delta_new = dot_lfvector(r, c, numverts);
 
-#ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
-	printf("==== A ====\n");
-	print_bfmatrix(lA);
-	printf("==== z ====\n");
-	print_lvector(z, numverts);
-	printf("==== B ====\n");
-	print_lvector(lB, numverts);
-	printf("==== S ====\n");
-	print_bfmatrix(S);
-#endif
+#  ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
+  printf("==== A ====\n");
+  print_bfmatrix(lA);
+  printf("==== z ====\n");
+  print_lvector(z, numverts);
+  printf("==== B ====\n");
+  print_lvector(lB, numverts);
+  printf("==== S ====\n");
+  print_bfmatrix(S);
+#  endif
 
-	while (delta_new > delta_target && conjgrad_loopcount < conjgrad_looplimit) {
-		mul_bfmatrix_lfvector(q, lA, c);
-		filter(q, S);
+  while (delta_new > delta_target && conjgrad_loopcount < conjgrad_looplimit) {
+    mul_bfmatrix_lfvector(q, lA, c);
+    filter(q, S);
 
-		alpha = delta_new / dot_lfvector(c, q, numverts);
+    alpha = delta_new / dot_lfvector(c, q, numverts);
 
-		add_lfvector_lfvectorS(ldV, ldV, c, alpha, numverts);
+    add_lfvector_lfvectorS(ldV, ldV, c, alpha, numverts);
 
-		add_lfvector_lfvectorS(r, r, q, -alpha, numverts);
+    add_lfvector_lfvectorS(r, r, q, -alpha, numverts);
 
-		/* s = P^-1 * r */
-		cp_lfvector(s, r, numverts);
-		delta_old = delta_new;
-		delta_new = dot_lfvector(r, s, numverts);
+    /* s = P^-1 * r */
+    cp_lfvector(s, r, numverts);
+    delta_old = delta_new;
+    delta_new = dot_lfvector(r, s, numverts);
 
-		add_lfvector_lfvectorS(c, s, c, delta_new / delta_old, numverts);
-		filter(c, S);
+    add_lfvector_lfvectorS(c, s, c, delta_new / delta_old, numverts);
+    filter(c, S);
 
-		conjgrad_loopcount++;
-	}
+    conjgrad_loopcount++;
+  }
 
-#ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
-	printf("==== dV ====\n");
-	print_lvector(ldV, numverts);
-	printf("========\n");
-#endif
+#  ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
+  printf("==== dV ====\n");
+  print_lvector(ldV, numverts);
+  printf("========\n");
+#  endif
 
-	del_lfvector(fB);
-	del_lfvector(AdV);
-	del_lfvector(r);
-	del_lfvector(c);
-	del_lfvector(q);
-	del_lfvector(s);
-	// printf("W/O conjgrad_loopcount: %d\n", conjgrad_loopcount);
-
-	result->status = conjgrad_loopcount < conjgrad_looplimit ? BPH_SOLVER_SUCCESS : BPH_SOLVER_NO_CONVERGENCE;
-	result->iterations = conjgrad_loopcount;
-	result->error = bnorm2 > 0.0f ? sqrtf(delta_new / bnorm2) : 0.0f;
-
-	return conjgrad_loopcount < conjgrad_looplimit;  // true means we reached desired accuracy in given time - ie stable
-}
-
-#if 0
+  del_lfvector(fB);
+  del_lfvector(AdV);
+  del_lfvector(r);
+  del_lfvector(c);
+  del_lfvector(q);
+  del_lfvector(s);
+  // printf("W/O conjgrad_loopcount: %d\n", conjgrad_loopcount);
+
+  result->status = conjgrad_loopcount < conjgrad_looplimit ? BPH_SOLVER_SUCCESS :
+                                                             BPH_SOLVER_NO_CONVERGENCE;
+  result->iterations = conjgrad_loopcount;
+  result->error = bnorm2 > 0.0f ? sqrtf(delta_new / bnorm2) : 0.0f;
+
+  return conjgrad_loopcount <
+         conjgrad_looplimit;  // true means we reached desired accuracy in given time - ie stable
+}
+
+#  if 0
 // block diagonalizer
 DO_INLINE void BuildPPinv(fmatrix3x3 *lA, fmatrix3x3 *P, fmatrix3x3 *Pinv)
 {
-	unsigned int i = 0;
+  unsigned int i = 0;
 
-	// Take only the diagonal blocks of A
+  // Take only the diagonal blocks of A
 // #pragma omp parallel for private(i) if (lA[0].vcount > CLOTH_OPENMP_LIMIT)
-	for (i = 0; i < lA[0].vcount; i++) {
-		// block diagonalizer
-		cp_fmatrix(P[i].m, lA[i].m);
-		inverse_fmatrix(Pinv[i].m, P[i].m);
+  for (i = 0; i < lA[0].vcount; i++) {
+    // block diagonalizer
+    cp_fmatrix(P[i].m, lA[i].m);
+    inverse_fmatrix(Pinv[i].m, P[i].m);
 
-	}
+  }
 }
 
-#if 0
+#    if 0
 // version 1.3
 static int cg_filtered_pre(lfVector *dv, fmatrix3x3 *lA, lfVector *lB, lfVector *z, fmatrix3x3 *S, fmatrix3x3 *P, fmatrix3x3 *Pinv)
 {
-	unsigned int numverts = lA[0].vcount, iterations = 0, conjgrad_looplimit = 100;
-	float delta0 = 0, deltaNew = 0, deltaOld = 0, alpha = 0;
-	float conjgrad_epsilon = 0.0001; // 0.2 is dt for steps=5
-	lfVector *r = create_lfvector(numverts);
-	lfVector *p = create_lfvector(numverts);
-	lfVector *s = create_lfvector(numverts);
-	lfVector *h = create_lfvector(numverts);
+  unsigned int numverts = lA[0].vcount, iterations = 0, conjgrad_looplimit = 100;
+  float delta0 = 0, deltaNew = 0, deltaOld = 0, alpha = 0;
+  float conjgrad_epsilon = 0.0001; // 0.2 is dt for steps=5
+  lfVector *r = create_lfvector(numverts);
+  lfVector *p = create_lfvector(numverts);
+  lfVector *s = create_lfvector(numverts);
+  lfVector *h = create_lfvector(numverts);
 
-	BuildPPinv(lA, P, Pinv);
+  BuildPPinv(lA, P, Pinv);
 
-	filter(dv, S);
-	add_lfvector_lfvector(dv, dv, z, numverts);
+  filter(dv, S);
+  add_lfvector_lfvector(dv, dv, z, numverts);
 
-	mul_bfmatrix_lfvector(r, lA, dv);
-	sub_lfvector_lfvector(r, lB, r, numverts);
-	filter(r, S);
+  mul_bfmatrix_lfvector(r, lA, dv);
+  sub_lfvector_lfvector(r, lB, r, numverts);
+  filter(r, S);
 
-	mul_prevfmatrix_lfvector(p, Pinv, r);
-	filter(p, S);
+  mul_prevfmatrix_lfvector(p, Pinv, r);
+  filter(p, S);
 
-	deltaNew = dot_lfvector(r, p, numverts);
+  deltaNew = dot_lfvector(r, p, numverts);
 
-	delta0 = deltaNew * sqrt(conjgrad_epsilon);
+  delta0 = deltaNew * sqrt(conjgrad_epsilon);
 
-#ifdef DEBUG_TIME
-	double start = PIL_check_seconds_timer();
-#endif
+#      ifdef DEBUG_TIME
+  double start = PIL_check_seconds_timer();
+#      endif
 
-	while ((deltaNew > delta0) && (iterations < conjgrad_looplimit))
-	{
-		iterations++;
+  while ((deltaNew > delta0) && (iterations < conjgrad_looplimit))
+  {
+    iterations++;
 
-		mul_bfmatrix_lfvector(s, lA, p);
-		filter(s, S);
+    mul_bfmatrix_lfvector(s, lA, p);
+    filter(s, S);
 
-		alpha = deltaNew / dot_lfvector(p, s, numverts);
+    alpha = deltaNew / dot_lfvector(p, s, numverts);
 
-		add_lfvector_lfvectorS(dv, dv, p, alpha, numverts);
+    add_lfvector_lfvectorS(dv, dv, p, alpha, numverts);
 
-		add_lfvector_lfvectorS(r, r, s, -alpha, numverts);
+    add_lfvector_lfvectorS(r, r, s, -alpha, numverts);
 
-		mul_prevfmatrix_lfvector(h, Pinv, r);
-		filter(h, S);
+    mul_prevfmatrix_lfvector(h, Pinv, r);
+    filter(h, S);
 
-		deltaOld = deltaNew;
+    deltaOld = deltaNew;
 
-		deltaNew = dot_lfvector(r, h, numverts);
+    deltaNew = dot_lfvector(r, h, numverts);
 
-		add_lfvector_lfvectorS(p, h, p, deltaNew / deltaOld, numverts);
+    add_lfvector_lfvectorS(p, h, p, deltaNew / deltaOld, numverts);
 
-		filter(p, S);
+    filter(p, S);
 
-	}
+  }
 
-#ifdef DEBUG_TIME
-	double end = PIL_check_seconds_timer();
-	printf("cg_filtered_pre time: %f\n", (float)(end - start));
-#endif
+#      ifdef DEBUG_TIME
+  double end = PIL_check_seconds_timer();
+  printf("cg_filtered_pre time: %f\n", (float)(end - start));
+#      endif
 
-	del_lfvector(h);
-	del_lfvector(s);
-	del_lfvector(p);
-	del_lfvector(r);
+  del_lfvector(h);
+  del_lfvector(s);
+  del_lfvector(p);
+  del_lfvector(r);
 
-	printf("iterations: %d\n", iterations);
+  printf("iterations: %d\n", iterations);
 
-	return iterations < conjgrad_looplimit;
+  return iterations < conjgrad_looplimit;
 }
-#endif
+#    endif
 
 // version 1.4
 static int cg_filtered_pre(lfVector *dv, fmatrix3x3 *lA, lfVector *lB, lfVector *z, fmatrix3x3 *S, fmatrix3x3 *P, fmatrix3x3 *Pinv, fmatrix3x3 *bigI)
 {
-	unsigned int numverts = lA[0].vcount, iterations = 0, conjgrad_looplimit = 100;
-	float delta0 = 0, deltaNew = 0, deltaOld = 0, alpha = 0, tol = 0;
-	lfVector *r = create_lfvector(numverts);
-	lfVector *p = create_lfvector(numverts);
-	lfVector *s = create_lfvector(numverts);
-	lfVector *h = create_lfvector(numverts);
-	lfVector *bhat = create_lfvector(numverts);
-	lfVector *btemp = create_lfvector(numverts);
+  unsigned int numverts = lA[0].vcount, iterations = 0, conjgrad_looplimit = 100;
+  float delta0 = 0, deltaNew = 0, deltaOld = 0, alpha = 0, tol = 0;
+  lfVector *r = create_lfvector(numverts);
+  lfVector *p = create_lfvector(numverts);
+  lfVector *s = create_lfvector(numverts);
+  lfVector *h = create_lfvector(numverts);
+  lfVector *bhat = create_lfvector(numverts);
+  lfVector *btemp = create_lfvector(numverts);
 
-	BuildPPinv(lA, P, Pinv);
+  BuildPPinv(lA, P, Pinv);
 
-	initdiag_bfmatrix(bigI, I);
-	sub_bfmatrix_Smatrix(bigI, bigI, S);
+  initdiag_bfmatrix(bigI, I);
+  sub_bfmatrix_Smatrix(bigI, bigI, S);
 
-	// x = Sx_0+(I-S)z
-	filter(dv, S);
-	add_lfvector_lfvector(dv, dv, z, numverts);
+  // x = Sx_0+(I-S)z
+  filter(dv, S);
+  add_lfvector_lfvector(dv, dv, z, numverts);
 
-	// b_hat = S(b-A(I-S)z)
-	mul_bfmatrix_lfvector(r, lA, z);
-	mul_bfmatrix_lfvector(bhat, bigI, r);
-	sub_lfvector_lfvector(bhat, lB, bhat, numverts);
+  // b_hat = S(b-A(I-S)z)
+  mul_bfmatrix_lfvector(r, lA, z);
+  mul_bfmatrix_lfvector(bhat, bigI, r);
+  sub_lfvector_lfvector(bhat, lB, bhat, numverts);
 
-	// r = S(b-Ax)
-	mul_bfmatrix_lfvector(r, lA, dv);
-	sub_lfvector_lfvector(r, lB, r, numverts);
-	filter(r, S);
+  // r = S(b-Ax)
+  mul_bfmatrix_lfvector(r, lA, dv);
+  sub_lfvector_lfvector(r, lB, r, numverts);
+  filter(r, S);
 
-	// p = SP^-1r
-	mul_prevfmatrix_lfvector(p, Pinv, r);
-	filter(p, S);
+  // p = SP^-1r
+  mul_prevfmatrix_lfvector(p, Pinv, r);
+  filter(p, S);
 
-	// delta0 = bhat^TP^-1bhat
-	mul_prevfmatrix_lfvector(btemp, Pinv, bhat);
-	delta0 = dot_lfvector(bhat, btemp, numverts);
+  // delta0 = bhat^TP^-1bhat
+  mul_prevfmatrix_lfvector(btemp, Pinv, bhat);
+  delta0 = dot_lfvector(bhat, btemp, numverts);
 
-	// deltaNew = r^TP
-	deltaNew = dot_lfvector(r, p, numverts);
+  // deltaNew = r^TP
+  deltaNew = dot_lfvector(r, p, numverts);
 
-#if 0
-	filter(dv, S);
-	add_lfvector_lfvector(dv, dv, z, numverts);
+#    if 0
+  filter(dv, S);
+  add_lfvector_lfvector(dv, dv, z, numverts);
 
-	mul_bfmatrix_lfvector(r, lA, dv);
-	sub_lfvector_lfvector(r, lB, r, numverts);
-	filter(r, S);
+  mul_bfmatrix_lfvector(r, lA, dv);
+  sub_lfvector_lfvector(r, lB, r, numverts);
+  filter(r, S);
 
-	mul_prevfmatrix_lfvector(p, Pinv, r);
-	filter(p, S);
+  mul_prevfmatrix_lfvector(p, Pinv, r);
+  filter(p, S);
 
-	deltaNew = dot_lfvector(r, p, numverts);
+  deltaNew = dot_lfvector(r, p, numverts);
 
-	delta0 = deltaNew * sqrt(conjgrad_epsilon);
-#endif
+  delta0 = deltaNew * sqrt(conjgrad_epsilon);
+#    endif
 
-#ifdef DEBUG_TIME
-	double start = PIL_check_seconds_timer();
-#endif
+#    ifdef DEBUG_TIME
+  double start = PIL_check_seconds_timer();
+#    endif
 
-	tol = (0.01 * 0.2);
+  tol = (0.01 * 0.2);
 
-	while ((deltaNew > delta0 * tol * tol) && (iterations < conjgrad_looplimit))
-	{
-		iterations++;
+  while ((deltaNew > delta0 * tol * tol) && (iterations < conjgrad_looplimit))
+  {
+    iterations++;
 
-		mul_bfmatrix_lfvector(s, lA, p);
-		filter(s, S);
+    mul_bfmatrix_lfvector(s, lA, p);
+    filter(s, S);
 
-		alpha = deltaNew / dot_lfvector(p, s, numverts);
+    alpha = deltaNew / dot_lfvector(p, s, numverts);
 
-		add_lfvector_lfvectorS(dv, dv, p, alpha, numverts);
+    add_lfvector_lfvectorS(dv, dv, p, alpha, numverts);
 
-		add_lfvector_lfvectorS(r, r, s, -alpha, numverts);
+    add_lfvector_lfvectorS(r, r, s, -alpha, numverts);
 
-		mul_prevfmatrix_lfvector(h, Pinv, r);
-		filter(h, S);
+    mul_prevfmatrix_lfvector(h, Pinv, r);
+    filter(h, S);
 
-		deltaOld = deltaNew;
+    deltaOld = deltaNew;
 
-		deltaNew = dot_lfvector(r, h, numverts);
+    deltaNew = dot_lfvector(r, h, numverts);
 
-		add_lfvector_lfvectorS(p, h, p, deltaNew / deltaOld, numverts);
+    add_lfvector_lfvectorS(p, h, p, deltaNew / deltaOld, numverts);
 
-		filter(p, S);
+    filter(p, S);
 
-	}
+  }
 
-#ifdef DEBUG_TIME
-	double end = PIL_check_seconds_timer();
-	printf("cg_filtered_pre time: %f\n", (float)(end - start));
-#endif
+#    ifdef DEBUG_TIME
+  double end = PIL_check_seconds_timer();
+  printf("cg_filtered_pre time: %f\n", (float)(end - start));
+#    endif
 
-	del_lfvector(btemp);
-	del_lfvector(bhat);
-	del_lfvector(h);
-	del_lfvector(s);
-	del_lfvector(p);
-	del_lfvector(r);
+  del_lfvector(btemp);
+  del_lfvector(bhat);
+  del_lfvector(h);
+  del_lfvector(s);
+  del_lfvector(p);
+  del_lfvector(r);
 
-	// printf("iterations: %d\n", iterations);
+  // printf("iterations: %d\n", iterations);
 
-	return iterations < conjgrad_looplimit;
+  return iterations < conjgrad_looplimit;
 }
-#endif
+#  endif
 
 bool BPH_mass_spring_solve_velocities(Implicit_Data *data, float dt, ImplicitSolverResult *result)
 {
-	unsigned int numverts = data->dFdV[0].vcount;
+  unsigned int numverts = data->dFdV[0].vcount;
 
-	lfVector *dFdXmV = create_lfvector(numverts);
-	zero_lfvector(data->dV, numverts);
+  lfVector *dFdXmV = create_lfvector(numverts);
+  zero_lfvector(data->dV, numverts);
 
-	cp_bfmatrix(data->A, data->M);
+  cp_bfmatrix(data->A, data->M);
 
-	subadd_bfmatrixS_bfmatrixS(data->A, data->dFdV, dt, data->dFdX, (dt * dt));
+  subadd_bfmatrixS_bfmatrixS(data->A, data->dFdV, dt, data->dFdX, (dt * dt));
 
-	mul_bfmatrix_lfvector(dFdXmV, data->dFdX, data->V);
+  mul_bfmatrix_lfvector(dFdXmV, data->dFdX, data->V);
 
-	add_lfvectorS_lfvectorS(data->B, data->F, dt, dFdXmV, (dt * dt), numverts);
+  add_lfvectorS_lfvectorS(data->B, data->F, dt, dFdXmV, (dt * dt), numverts);
 
-#ifdef DEBUG_TIME
-	double start = PIL_check_seconds_timer();
-#endif
+#  ifdef DEBUG_TIME
+  double start = PIL_check_seconds_timer();
+#  endif
 
-	cg_filtered(data->dV, data->A, data->B, data->z, data->S, result); /* conjugate gradient algorithm to solve Ax=b */
-	// cg_filtered_pre(id->dV, id->A, id->B, id->z, id->S, id->P, id->Pinv, id->bigI);
+  cg_filtered(data->dV,
+              data->A,
+              data->B,
+              data->z,
+              data->S,
+              result); /* conjugate gradient algorithm to solve Ax=b */
+  // cg_filtered_pre(id->dV, id->A, id->B, id->z, id->S, id->P, id->Pinv, id->bigI);
 
-#ifdef DEBUG_TIME
-	double end = PIL_check_seconds_timer();
-	printf("cg_filtered calc time: %f\n", (float)(end - start));
-#endif
+#  ifdef DEBUG_TIME
+  double end = PIL_check_seconds_timer();
+  printf("cg_filtered calc time: %f\n", (float)(end - start));
+#  endif
 
-	// advance velocities
-	add_lfvector_lfvector(data->Vnew, data->V, data->dV, numverts);
+  // advance velocities
+  add_lfvector_lfvector(data->Vnew, data->V, data->dV, numverts);
 
-	del_lfvector(dFdXmV);
+  del_lfvector(dFdXmV);
 
-	return result->status == BPH_SOLVER_SUCCESS;
+  return result->status == BPH_SOLVER_SUCCESS;
 }
 
 bool BPH_mass_spring_solve_positions(Implicit_Data *data, float dt)
 {
-	int numverts = data->M[0].vcount;
+  int numverts = data->M[0].vcount;
 
-	// advance positions
-	add_lfvector_lfvectorS(data->Xnew, data->X, data->Vnew, dt, numverts);
+  // advance positions
+  add_lfvector_lfvectorS(data->Xnew, data->X, data->Vnew, dt, numverts);
 
-	return true;
+  return true;
 }
 
 void BPH_mass_spring_apply_result(Implicit_Data *data)
 {
-	int numverts = data->M[0].vcount;
-	cp_lfvector(data->X, data->Xnew, numverts);
-	cp_lfvector(data->V, data->Vnew, numverts);
+  int numverts = data->M[0].vcount;
+  cp_lfvector(data->X, data->Xnew, numverts);
+  cp_lfvector(data->V, data->Vnew, numverts);
 }
 
 void BPH_mass_spring_set_vertex_mass(Implicit_Data *data, int index, float mass)
 {
-	unit_m3(data->M[index].m);
-	mul_m3_fl(data->M[index].m, mass);
+  unit_m3(data->M[index].m);
+  mul_m3_fl(data->M[index].m, mass);
 }
 
 void BPH_mass_spring_set_rest_transform(Implicit_Data *data, int index, float tfm[3][3])
 {
-#ifdef CLOTH_ROOT_FRAME
-	copy_m3_m3(data->tfm[index].m, tfm);
-#else
-	unit_m3(data->tfm[index].m);
-	(void)tfm;
-#endif
+#  ifdef CLOTH_ROOT_FRAME
+  copy_m3_m3(data->tfm[index].m, tfm);
+#  else
+  unit_m3(data->tfm[index].m);
+  (void)tfm;
+#  endif
 }
 
-void BPH_mass_spring_set_motion_state(Implicit_Data *data, int index, const float x[3], const float v[3])
+void BPH_mass_spring_set_motion_state(Implicit_Data *data,
+                                      int index,
+                                      const float x[3],
+                                      const float v[3])
 {
-	world_to_root_v3(data, index, data->X[index], x);
-	world_to_root_v3(data, index, data->V[index], v);
+  world_to_root_v3(data, index, data->X[index], x);
+  world_to_root_v3(data, index, data->V[index], v);
 }
 
 void BPH_mass_spring_set_position(Implicit_Data *data, int index, const float x[3])
 {
-	world_to_root_v3(data, index, data->X[index], x);
+  world_to_root_v3(data, index, data->X[index], x);
 }
 
 void BPH_mass_spring_set_velocity(Implicit_Data *data, int index, const float v[3])
 {
-	world_to_root_v3(data, index, data->V[index], v);
+  world_to_root_v3(data, index, data->V[index], v);
 }
 
-void BPH_mass_spring_get_motion_state(struct Implicit_Data *data, int index, float x[3], float v[3])
+void BPH_mass_spring_get_motion_state(struct Implicit_Data *data,
+                                      int index,
+                                      float x[3],
+                                      float v[3])
 {
-	if (x) root_to_world_v3(data, index, x, data->X[index]);
-	if (v) root_to_world_v3(data, index, v, data->V[index]);
+  if (x)
+    root_to_world_v3(data, index, x, data->X[index]);
+  if (v)
+    root_to_world_v3(data, index, v, data->V[index]);
 }
 
 void BPH_mass_spring_get_position(struct Implicit_Data *data, int index, float x[3])
 {
-	root_to_world_v3(data, index, x, data->X[index]);
+  root_to_world_v3(data, index, x, data->X[index]);
 }
 
 void BPH_mass_spring_get_new_position(struct Implicit_Data *data, int index, float x[3])
 {
-	root_to_world_v3(data, index, x, data->Xnew[index]);
+  root_to_world_v3(data, index, x, data->Xnew[index]);
 }
 
 void BPH_mass_spring_set_new_position(struct Implicit_Data *data, int index, const float x[3])
 {
-	world_to_root_v3(data, index, data->Xnew[index], x);
+  world_to_root_v3(data, index, data->Xnew[index], x);
 }
 
 void BPH_mass_spring_get_new_velocity(struct Implicit_Data *data, int index, float v[3])
 {
-	root_to_world_v3(data, index, v, data->Vnew[index]);
+  root_to_world_v3(data, index, v, data->Vnew[index]);
 }
 
 void BPH_mass_spring_set_new_velocity(struct Implicit_Data *data, int index, const float v[3])
 {
-	world_to_root_v3(data, index, data->Vnew[index], v);
+  world_to_root_v3(data, index, data->Vnew[index], v);
 }
 
 /* -------------------------------- */
 
 static int BPH_mass_spring_add_block(Implicit_Data *data, int v1, int v2)
 {
-	int s = data->M[0].vcount + data->num_blocks; /* index from array start */
-	BLI_assert(s < data->M[0].vcount + data->M[0].scount);
-	++data->num_blocks;
+  int s = data->M[0].vcount + data->num_blocks; /* index from array start */
+  BLI_assert(s < data->M[0].vcount + data->M[0].scount);
+  ++data->num_blocks;
 
-	/* tfm and S don't have spring entries (diagonal blocks only) */
-	init_fmatrix(data->bigI + s, v1, v2);
-	init_fmatrix(data->M + s, v1, v2);
-	init_fmatrix(data->dFdX + s, v1, v2);
-	init_fmatrix(data->dFdV + s, v1, v2);
-	init_fmatrix(data->A + s, v1, v2);
-	init_fmatrix(data->P + s, v1, v2);
-	init_fmatrix(data->Pinv + s, v1, v2);
+  /* tfm and S don't have spring entries (diagonal blocks only) */
+  init_fmatrix(data->bigI + s, v1, v2);
+  init_fmatrix(data->M + s, v1, v2);
+  init_fmatrix(data->dFdX + s, v1, v2);
+  init_fmatrix(data->dFdV + s, v1, v2);
+  init_fmatrix(data->A + s, v1, v2);
+  init_fmatrix(data->P + s, v1, v2);
+  init_fmatrix(data->Pinv + s, v1, v2);
 
-	return s;
+  return s;
 }
 
 void BPH_mass_spring_clear_constraints(Implicit_Data *data)
 {
-	int i, numverts = data->S[0].vcount;
-	for (i = 0; i < numverts; ++i) {
-		unit_m3(data->S[i].m);
-		zero_v3(data->z[i]);
-	}
+  int i, numverts = data->S[0].vcount;
+  for (i = 0; i < numverts; ++i) {
+    unit_m3(data->S[i].m);
+    zero_v3(data->z[i]);
+  }
 }
 
 void BPH_mass_spring_add_constraint_ndof0(Implicit_Data *data, int index, const float dV[3])
 {
-	zero_m3(data->S[index].m);
+  zero_m3(data->S[index].m);
 
-	world_to_root_v3(data, index, data->z[index], dV);
+  world_to_root_v3(data, index, data->z[index], dV);
 }
 
-void BPH_mass_spring_add_constraint_ndof1(Implicit_Data *data, int index, const float c1[3], const float c2[3], const float dV[3])
+void BPH_mass_spring_add_constraint_ndof1(
+    Implicit_Data *data, int index, const float c1[3], const float c2[3], const float dV[3])
 {
-	float m[3][3], p[3], q[3], u[3], cmat[3][3];
+  float m[3][3], p[3], q[3], u[3], cmat[3][3];
 
-	world_to_root_v3(data, index, p, c1);
-	mul_fvectorT_fvector(cmat, p, p);
-	sub_m3_m3m3(m, I, cmat);
+  world_to_root_v3(data, index, p, c1);
+  mul_fvectorT_fvector(cmat, p, p);
+  sub_m3_m3m3(m, I, cmat);
 
-	world_to_root_v3(data, index, q, c2);
-	mul_fvectorT_fvector(cmat, q, q);
-	sub_m3_m3m3(m, m, cmat);
+  world_to_root_v3(data, index, q, c2);
+  mul_fvectorT_fvector(cmat, q, q);
+  sub_m3_m3m3(m, m, cmat);
 
-	/* XXX not sure but multiplication should work here */
-	copy_m3_m3(data->S[index].m, m);
-//	mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
+  /* XXX not sure but multiplication should work here */
+  copy_m3_m3(data->S[index].m, m);
+  //  mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
 
-	world_to_root_v3(data, index, u, dV);
-	add_v3_v3(data->z[index], u);
+  world_to_root_v3(data, index, u, dV);
+  add_v3_v3(data->z[index], u);
 }
 
-void BPH_mass_spring_add_constraint_ndof2(Implicit_Data *data, int index, const float c1[3], const float dV[3])
+void BPH_mass_spring_add_constraint_ndof2(Implicit_Data *data,
+                                          int index,
+                                          const float c1[3],
+                                          const float dV[3])
 {
-	float m[3][3], p[3], u[3], cmat[3][3];
+  float m[3][3], p[3], u[3], cmat[3][3];
 
-	world_to_root_v3(data, index, p, c1);
-	mul_fvectorT_fvector(cmat, p, p);
-	sub_m3_m3m3(m, I, cmat);
+  world_to_root_v3(data, index, p, c1);
+  mul_fvectorT_fvector(cmat, p, p);
+  sub_m3_m3m3(m, I, cmat);
 
-	copy_m3_m3(data->S[index].m, m);
-//	mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
+  copy_m3_m3(data->S[index].m, m);
+  //  mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
 
-	world_to_root_v3(data, index, u, dV);
-	add_v3_v3(data->z[index], u);
+  world_to_root_v3(data, index, u, dV);
+  add_v3_v3(data->z[index], u);
 }
 
 void BPH_mass_spring_clear_forces(Implicit_Data *data)
 {
-	int numverts = data->M[0].vcount;
-	zero_lfvector(data->F, numverts);
-	init_bfmatrix(data->dFdX, ZERO);
-	init_bfmatrix(data->dFdV, ZERO);
-
-	data->num_blocks = 0;
-}
-
-void BPH_mass_spring_force_reference_frame(Implicit_Data *data, int index, const float acceleration[3], const float omega[3], const float domega_dt[3], float mass)
-{
-#ifdef CLOTH_ROOT_FRAME
-	float acc[3], w[3], dwdt[3];
-	float f[3], dfdx[3][3], dfdv[3][3];
-	float euler[3], coriolis[3], centrifugal[3], rotvel[3];
-	float deuler[3][3], dcoriolis[3][3], dcentrifugal[3][3], drotvel[3][3];
-
-	world_to_root_v3(data, index, acc, acceleration);
-	world_to_root_v3(data, index, w, omega);
-	world_to_root_v3(data, index, dwdt, domega_dt);
-
-	cross_v3_v3v3(euler, dwdt, data->X[index]);
-	cross_v3_v3v3(coriolis, w, data->V[index]);
-	mul_v3_fl(coriolis, 2.0f);
-	cross_v3_v3v3(rotvel, w, data->X[index]);
-	cross_v3_v3v3(centrifugal, w, rotvel);
-
-	sub_v3_v3v3(f, acc, euler);
-	sub_v3_v3(f, coriolis);
-	sub_v3_v3(f, centrifugal);
-
-	mul_v3_fl(f, mass); /* F = m * a */
-
-	cross_v3_identity(deuler, dwdt);
-	cross_v3_identity(dcoriolis, w);
-	mul_m3_fl(dcoriolis, 2.0f);
-	cross_v3_identity(drotvel, w);
-	cross_m3_v3m3(dcentrifugal, w, drotvel);
-
-	add_m3_m3m3(dfdx, deuler, dcentrifugal);
-	negate_m3(dfdx);
-	mul_m3_fl(dfdx, mass);
-
-	copy_m3_m3(dfdv, dcoriolis);
-	negate_m3(dfdv);
-	mul_m3_fl(dfdv, mass);
-
-	add_v3_v3(data->F[index], f);
-	add_m3_m3m3(data->dFdX[index].m, data->dFdX[index].m, dfdx);
-	add_m3_m3m3(data->dFdV[index].m, data->dFdV[index].m, dfdv);
-#else
-	(void)data;
-	(void)index;
-	(void)acceleration;
-	(void)omega;
-	(void)domega_dt;
-#endif
+  int numverts = data->M[0].vcount;
+  zero_lfvector(data->F, numverts);
+  init_bfmatrix(data->dFdX, ZERO);
+  init_bfmatrix(data->dFdV, ZERO);
+
+  data->num_blocks = 0;
+}
+
+void BPH_mass_spring_force_reference_frame(Implicit_Data *data,
+                                           int index,
+                                           const float acceleration[3],
+                                           const float omega[3],
+                                           const float domega_dt[3],
+                                           float mass)
+{
+#  ifdef CLOTH_ROOT_FRAME
+  float acc[3], w[3], dwdt[3];
+  float f[3], dfdx[3][3], dfdv[3][3];
+  float euler[3], coriolis[3], centrifugal[3], rotvel[3];
+  float deuler[3][3], dcoriolis[3][3], dcentrifugal[3][3], drotvel[3][3];
+
+  world_to_root_v3(data, index, acc, acceleration);
+  world_to_root_v3(data, index, w, omega);
+  world_to_root_v3(data, index, dwdt, domega_dt);
+
+  cross_v3_v3v3(euler, dwdt, data->X[index]);
+  cross_v3_v3v3(coriolis, w, data->V[index]);
+  mul_v3_fl(coriolis, 2.0f);
+  cross_v3_v3v3(rotvel, w, data->X[index]);
+  cross_v3_v3v3(centrifugal, w, rotvel);
+
+  sub_v3_v3v3(f, acc, euler);
+  sub_v3_v3(f, coriolis);
+  sub_v3_v3(f, centrifugal);
+
+  mul_v3_fl(f, mass); /* F = m * a */
+
+  cross_v3_identity(deuler, dwdt);
+  cross_v3_identity(dcoriolis, w);
+  mul_m3_fl(dcoriolis, 2.0f);
+  cross_v3_identity(drotvel, w);
+  cross_m3_v3m3(dcentrifugal, w, drotvel);
+
+  add_m3_m3m3(dfdx, deuler, dcentrifugal);
+  negate_m3(dfdx);
+  mul_m3_fl(dfdx, mass);
+
+  copy_m3_m3(dfdv, dcoriolis);
+  negate_m3(dfdv);
+  mul_m3_fl(dfdv, mass);
+
+  add_v3_v3(data->F[index], f);
+  add_m3_m3m3(data->dFdX[index].m, data->dFdX[index].m, dfdx);
+  add_m3_m3m3(data->dFdV[index].m, data->dFdV[index].m, dfdv);
+#  else
+  (void)data;
+  (void)index;
+  (void)acceleration;
+  (void)omega;
+  (void)domega_dt;
+#  endif
 }
 
 void BPH_mass_spring_force_gravity(Implicit_Data *data, int index, float mass, const float g[3])
 {
-	/* force = mass * acceleration (in this case: gravity) */
-	float f[3];
-	world_to_root_v3(data, index, f, g);
-	mul_v3_fl(f, mass);
+  /* force = mass * acceleration (in this case: gravity) */
+  float f[3];
+  world_to_root_v3(data, index, f, g);
+  mul_v3_fl(f, mass);
 
-	add_v3_v3(data->F[index], f);
+  add_v3_v3(data->F[index], f);
 }
 
 void BPH_mass_spring_force_drag(Implicit_Data *data, float drag)
 {
-	int i, numverts = data->M[0].vcount;
-	for (i = 0; i < numverts; i++) {
-		float tmp[3][3];
+  int i, numverts = data->M[0].vcount;
+  for (i = 0; i < numverts; i++) {
+    float tmp[3][3];
 
-		/* NB: uses root space velocity, no need to transform */
-		madd_v3_v3fl(data->F[i], data->V[i], -drag);
+    /* NB: uses root space velocity, no need to transform */
+    madd_v3_v3fl(data->F[i], data->V[i], -drag);
 
-		copy_m3_m3(tmp, I);
-		mul_m3_fl(tmp, -drag);
-		add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, tmp);
-	}
+    copy_m3_m3(tmp, I);
+    mul_m3_fl(tmp, -drag);
+    add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, tmp);
+  }
 }
 
-void BPH_mass_spring_force_extern(struct Implicit_Data *data, int i, const float f[3], float dfdx[3][3], float dfdv[3][3])
+void BPH_mass_spring_force_extern(
+    struct Implicit_Data *data, int i, const float f[3], float dfdx[3][3], float dfdv[3][3])
 {
-	float tf[3], tdfdx[3][3], tdfdv[3][3];
-	world_to_root_v3(data, i, tf, f);
-	world_to_root_m3(data, i, tdfdx, dfdx);
-	world_to_root_m3(data, i, tdfdv, dfdv);
+  float tf[3], tdfdx[3][3], tdfdv[3][3];
+  world_to_root_v3(data, i, tf, f);
+  world_to_root_m3(data, i, tdfdx, dfdx);
+  world_to_root_m3(data, i, tdfdv, dfdv);
 
-	add_v3_v3(data->F[i], tf);
-	add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, tdfdx);
-	add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, tdfdv);
+  add_v3_v3(data->F[i], tf);
+  add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, tdfdx);
+  add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, tdfdv);
 }
 
-static float calc_nor_area_tri(float nor[3], const float v1[3], const float v2[3], const float v3[3])
+static float calc_nor_area_tri(float nor[3],
+                               const float v1[3],
+                               const float v2[3],
+                               const float v3[3])
 {
-	float n1[3], n2[3];
+  float n1[3], n2[3];
 
-	sub_v3_v3v3(n1, v1, v2);
-	sub_v3_v3v3(n2, v2, v3);
+  sub_v3_v3v3(n1, v1, v2);
+  sub_v3_v3v3(n2, v2, v3);
 
-	cross_v3_v3v3(nor, n1, n2);
-	return normalize_v3(nor);
+  cross_v3_v3v3(nor, n1, n2);
+  return normalize_v3(nor);
 }
 
 /* XXX does not support force jacobians yet, since the effector system does not provide them either */
-void BPH_mass_spring_force_face_wind(Implicit_Data *data, int v1, int v2, int v3, const float(*winvec)[3])
+void BPH_mass_spring_force_face_wind(
+    Implicit_Data *data, int v1, int v2, int v3, const float (*winvec)[3])
 {
-	const float effector_scale = 0.02f;
-	float win[3], nor[3], area;
-	float factor;
+  const float effector_scale = 0.02f;
+  float win[3], nor[3], area;
+  float factor;
 
-	/* calculate face normal and area */
-	area = calc_nor_area_tri(nor, data->X[v1], data->X[v2], data->X[v3]);
-	factor = effector_scale * area / 3.0f;
+  /* calculate face normal and area */
+  area = calc_nor_area_tri(nor, data->X[v1], data->X[v2], data->X[v3]);
+  factor = effector_scale * area / 3.0f;
 
-	world_to_root_v3(data, v1, win, winvec[v1]);
-	madd_v3_v3fl(data->F[v1], nor, factor * dot_v3v3(win, nor));
+  world_to_root_v3(data, v1, win, winvec[v1]);
+  madd_v3_v3fl(data->F[v1], nor, factor * dot_v3v3(win, nor));
 
-	world_to_root_v3(data, v2, win, winvec[v2]);
-	madd_v3_v3fl(data->F[v2], nor, factor * dot_v3v3(win, nor));
+  world_to_root_v3(data, v2, win, winvec[v2]);
+  madd_v3_v3fl(data->F[v2], nor, factor * dot_v3v3(win, nor));
 
-	world_to_root_v3(data, v3, win, winvec[v3]);
-	madd_v3_v3fl(data->F[v3], nor, factor * dot_v3v3(win, nor));
+  world_to_root_v3(data, v3, win, winvec[v3]);
+  madd_v3_v3fl(data->F[v3], nor, factor * dot_v3v3(win, nor));
 }
 
-static void edge_wind_vertex(const float dir[3], float length, float radius, const float wind[3], float f[3], float UNUSED(dfdx[3][3]), float UNUSED(dfdv[3][3]))
+static void edge_wind_vertex(const float dir[3],
+                             float length,
+                             float radius,
+                             const float wind[3],
+                             float f[3],
+                             float UNUSED(dfdx[3][3]),
+                             float UNUSED(dfdv[3][3]))
 {
-	const float density = 0.01f; /* XXX arbitrary value, corresponds to effect of air density */
-	float cos_alpha, sin_alpha, cross_section;
-	float windlen = len_v3(wind);
+  const float density = 0.01f; /* XXX arbitrary value, corresponds to effect of air density */
+  float cos_alpha, sin_alpha, cross_section;
+  float windlen = len_v3(wind);
 
-	if (windlen == 0.0f) {
-		zero_v3(f);
-		return;
-	}
+  if (windlen == 0.0f) {
+    zero_v3(f);
+    return;
+  }
 
-	/* angle of wind direction to edge */
-	cos_alpha = dot_v3v3(wind, dir) / windlen;
-	sin_alpha = sqrtf(1.0f - cos_alpha * cos_alpha);
-	cross_section = radius * ((float)M_PI * radius * sin_alpha + length * cos_alpha);
+  /* angle of wind direction to edge */
+  cos_alpha = dot_v3v3(wind, dir) / windlen;
+  sin_alpha = sqrtf(1.0f - cos_alpha * cos_alpha);
+  cross_section = radius * ((float)M_PI * radius * sin_alpha + length * cos_alpha);
 
-	mul_v3_v3fl(f, wind, density * cross_section);
+  mul_v3_v3fl(f, wind, density * cross_section);
 }
 
-void BPH_mass_spring_force_edge_wind(Implicit_Data *data, int v1, int v2, float radius1, float radius2, const float(*winvec)[3])
+void BPH_mass_spring_force_edge_wind(
+    Implicit_Data *data, int v1, int v2, float radius1, float radius2, const float (*winvec)[3])
 {
-	float win[3], dir[3], length;
-	float f[3], dfdx[3][3], dfdv[3][3];
+  float win[3], dir[3], length;
+  float f[3], dfdx[3][3], dfdv[3][3];
 
-	sub_v3_v3v3(dir, data->X[v1], data->X[v2]);
-	length = normalize_v3(dir);
+  sub_v3_v3v3(dir, data->X[v1], data->X[v2]);
+  length = normalize_v3(dir);
 
-	world_to_root_v3(data, v1, win, winvec[v1]);
-	edge_wind_vertex(dir, length, radius1, win, f, dfdx, dfdv);
-	add_v3_v3(data->F[v1], f);
+  world_to_root_v3(data, v1, win, winvec[v1]);
+  edge_wind_vertex(dir, length, radius1, win, f, dfdx, dfdv);
+  add_v3_v3(data->F[v1], f);
 
-	world_to_root_v3(data, v2, win, winvec[v2]);
-	edge_wind_vertex(dir, length, radius2, win, f, dfdx, dfdv);
-	add_v3_v3(data->F[v2], f);
+  world_to_root_v3(data, v2, win, winvec[v2]);
+  edge_wind_vertex(dir, length, radius2, win, f, dfdx, dfdv);
+  add_v3_v3(data->F[v2], f);
 }
 
-void BPH_mass_spring_force_vertex_wind(Implicit_Data *data, int v, float UNUSED(radius), const float(*winvec)[3])
+void BPH_mass_spring_force_vertex_wind(Implicit_Data *data,
+                                       int v,
+                                       float UNUSED(radius),
+                                       const float (*winvec)[3])
 {
-	const float density = 0.01f; /* XXX arbitrary value, corresponds to effect of air density */
+  const float density = 0.01f; /* XXX arbitrary value, corresponds to effect of air density */
 
-	float wind[3];
-	float f[3];
+  float wind[3];
+  float f[3];
 
-	world_to_root_v3(data, v, wind, winvec[v]);
-	mul_v3_v3fl(f, wind, density);
-	add_v3_v3(data->F[v], f);
+  world_to_root_v3(data, v, wind, winvec[v]);
+  mul_v3_v3fl(f, wind, density);
+  add_v3_v3(data->F[v], f);
 }
 
 BLI_INLINE void dfdx_spring(float to[3][3], const float dir[3], float length, float L, float k)
 {
-	// dir is unit length direction, rest is spring's restlength, k is spring constant.
-	//return  ( (I-outerprod(dir, dir))*Min(1.0f, rest/length) - I) * -k;
-	outerproduct(to, dir, dir);
-	sub_m3_m3m3(to, I, to);
+  // dir is unit length direction, rest is spring's restlength, k is spring constant.
+  //return  ( (I-outerprod(dir, dir))*Min(1.0f, rest/length) - I) * -k;
+  outerproduct(to, dir, dir);
+  sub_m3_m3m3(to, I, to);
 
-	mul_m3_fl(to, (L / length));
-	sub_m3_m3m3(to, to, I);
-	mul_m3_fl(to, k);
+  mul_m3_fl(to, (L / length));
+  sub_m3_m3m3(to, to, I);
+  mul_m3_fl(to, k);
 }
 
 /* unused */
-#if 0
+#  if 0
 BLI_INLINE void dfdx_damp(float to[3][3], const float dir[3], float length, const float vel[3], float rest, float damping)
 {
-	// inner spring damping   vel is the relative velocity  of the endpoints.
-	//  return (I-outerprod(dir, dir)) * (-damping * -(dot(dir, vel)/Max(length, rest)));
-	mul_fvectorT_fvector(to, dir, dir);
-	sub_fmatrix_fmatrix(to, I, to);
-	mul_fmatrix_S(to,  (-damping * -(dot_v3v3(dir, vel) / MAX2(length, rest))));
+  // inner spring damping   vel is the relative velocity  of the endpoints.
+  //  return (I-outerprod(dir, dir)) * (-damping * -(dot(dir, vel)/Max(length, rest)));
+  mul_fvectorT_fvector(to, dir, dir);
+  sub_fmatrix_fmatrix(to, I, to);
+  mul_fmatrix_S(to,  (-damping * -(dot_v3v3(dir, vel) / MAX2(length, rest))));
 }
-#endif
+#  endif
 
 BLI_INLINE void dfdv_damp(float to[3][3], const float dir[3], float damping)
 {
-	// derivative of force wrt velocity
-	outerproduct(to, dir, dir);
-	mul_m3_fl(to, -damping);
+  // derivative of force wrt velocity
+  outerproduct(to, dir, dir);
+  mul_m3_fl(to, -damping);
 }
 
 BLI_INLINE float fb(float length, float L)
 {
-	float x = length / L;
-	float xx = x * x;
-	float xxx = xx * x;
-	float xxxx = xxx * x;
-	return (-11.541f * xxxx + 34.193f * xxx - 39.083f * xx + 23.116f * x - 9.713f);
+  float x = length / L;
+  float xx = x * x;
+  float xxx = xx * x;
+  float xxxx = xxx * x;
+  return (-11.541f * xxxx + 34.193f * xxx - 39.083f * xx + 23.116f * x - 9.713f);
 }
 
 BLI_INLINE float fbderiv(float length, float L)
 {
-	float x = length / L;
-	float xx = x * x;
-	float xxx = xx * x;
-	return (-46.164f * xxx + 102.579f * xx - 78.166f * x + 23.116f);
+  float x = length / L;
+  float xx = x * x;
+  float xxx = xx * x;
+  return (-46.164f * xxx + 102.579f * xx - 78.166f * x + 23.116f);
 }
 
 BLI_INLINE float fbstar(float length, float L, float kb, float cb)
 {
-	float tempfb_fl = kb * fb(length, L);
-	float fbstar_fl = cb * (length - L);
+  float tempfb_fl = kb * fb(length, L);
+  float fbstar_fl = cb * (length - L);
 
-	if (tempfb_fl < fbstar_fl)
-		return fbstar_fl;
-	else
-		return tempfb_fl;
+  if (tempfb_fl < fbstar_fl)
+    return fbstar_fl;
+  else
+    return tempfb_fl;
 }
 
 // function to calculae bending spring force (taken from Choi & Co)
 BLI_INLINE float fbstar_jacobi(float length, float L, float kb, float cb)
 {
-	float tempfb_fl = kb * fb(length, L);
-	float fbstar_fl = cb * (length - L);
+  float tempfb_fl = kb * fb(length, L);
+  float fbstar_fl = cb * (length - L);
 
-	if (tempfb_fl < fbstar_fl) {
-		return -cb;
-	}
-	else {
-		return -kb *fbderiv(length, L);
-	}
+  if (tempfb_fl < fbstar_fl) {
+    return -cb;
+  }
+  else {
+    return -kb * fbderiv(length, L);
+  }
 }
 
 /* calculate elonglation */
-BLI_INLINE bool spring_length(Implicit_Data *data, int i, int j, float r_extent[3], float r_dir[3], float *r_length, float r_vel[3])
-{
-	sub_v3_v3v3(r_extent, data->X[j], data->X[i]);
-	sub_v3_v3v3(r_vel, data->V[j], data->V[i]);
-	*r_length = len_v3(r_extent);
-
-	if (*r_length > ALMOST_ZERO) {
-#if 0
-		if (length > L) {
-			if ((clmd->sim_parms->flags & CSIMSETT_FLAG_TEARING_ENABLED) &&
-			    ( ((length - L) * 100.0f / L) > clmd->sim_parms->maxspringlen))
-			{
-				// cut spring!
-				s->flags |= CSPRING_FLAG_DEACTIVATE;
-				return false;
-			}
-		}
-#endif
-		mul_v3_v3fl(r_dir, r_extent, 1.0f / (*r_length));
-	}
-	else {
-		zero_v3(r_dir);
-	}
-
-	return true;
-}
-
-BLI_INLINE void apply_spring(Implicit_Data *data, int i, int j, const float f[3], float dfdx[3][3], float dfdv[3][3])
-{
-	int block_ij = BPH_mass_spring_add_block(data, i, j);
-
-	add_v3_v3(data->F[i], f);
-	sub_v3_v3(data->F[j], f);
-
-	add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfdx);
-	add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfdx);
-	sub_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfdx);
-
-	add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, dfdv);
-	add_m3_m3m3(data->dFdV[j].m, data->dFdV[j].m, dfdv);
-	sub_m3_m3m3(data->dFdV[block_ij].m, data->dFdV[block_ij].m, dfdv);
-}
-
-bool BPH_mass_spring_force_spring_linear(Implicit_Data *data, int i, int j, float restlen,
-                                         float stiffness_tension, float damping_tension,
-                                         float stiffness_compression, float damping_compression,
-                                         bool resist_compress, bool new_compress, float clamp_force)
-{
-	float extent[3], length, dir[3], vel[3];
-	float f[3], dfdx[3][3], dfdv[3][3];
-	float damping = 0;
-
-	// calculate elonglation
-	spring_length(data, i, j, extent, dir, &length, vel);
-
-	/* This code computes not only the force, but also its derivative.
-	   Zero derivative effectively disables the spring for the implicit solver.
-	   Thus length > restlen makes cloth unconstrained at the start of simulation. */
-	if ((length >= restlen && length > 0) || resist_compress) {
-		float stretch_force;
-
-		damping = damping_tension;
-
-		stretch_force = stiffness_tension * (length - restlen);
-		if (clamp_force > 0.0f && stretch_force > clamp_force) {
-			stretch_force = clamp_force;
-		}
-		mul_v3_v3fl(f, dir, stretch_force);
-
-		dfdx_spring(dfdx, dir, length, restlen, stiffness_tension);
-	}
-	else if (new_compress) {
-		/* This is based on the Choi and Ko bending model, which works surprisingly well for compression. */
-		float kb = stiffness_compression;
-		float cb = kb; /* cb equal to kb seems to work, but a factor can be added if necessary */
-
-		damping = damping_compression;
-
-		mul_v3_v3fl(f, dir, fbstar(length, restlen, kb, cb));
-
-		outerproduct(dfdx, dir, dir);
-		mul_m3_fl(dfdx, fbstar_jacobi(length, restlen, kb, cb));
-	}
-	else {
-		return false;
-	}
-
-	madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
-	dfdv_damp(dfdv, dir, damping);
-
-	apply_spring(data, i, j, f, dfdx, dfdv);
-
-	return true;
+BLI_INLINE bool spring_length(Implicit_Data *data,
+                              int i,
+                              int j,
+                              float r_extent[3],
+                              float r_dir[3],
+                              float *r_length,
+                              float r_vel[3])
+{
+  sub_v3_v3v3(r_extent, data->X[j], data->X[i]);
+  sub_v3_v3v3(r_vel, data->V[j], data->V[i]);
+  *r_length = len_v3(r_extent);
+
+  if (*r_length > ALMOST_ZERO) {
+#  if 0
+    if (length > L) {
+      if ((clmd->sim_parms->flags & CSIMSETT_FLAG_TEARING_ENABLED) &&
+          ( ((length - L) * 100.0f / L) > clmd->sim_parms->maxspringlen))
+      {
+        // cut spring!
+        s->flags |= CSPRING_FLAG_DEACTIVATE;
+        return false;
+      }
+    }
+#  endif
+    mul_v3_v3fl(r_dir, r_extent, 1.0f / (*r_length));
+  }
+  else {
+    zero_v3(r_dir);
+  }
+
+  return true;
+}
+
+BLI_INLINE void apply_spring(
+    Implicit_Data *data, int i, int j, const float f[3], float dfdx[3][3], float dfdv[3][3])
+{
+  int block_ij = BPH_mass_spring_add_block(data, i, j);
+
+  add_v3_v3(data->F[i], f);
+  sub_v3_v3(data->F[j], f);
+
+  add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfdx);
+  add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfdx);
+  sub_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfdx);
+
+  add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, dfdv);
+  add_m3_m3m3(data->dFdV[j].m, data->dFdV[j].m, dfdv);
+  sub_m3_m3m3(data->dFdV[block_ij].m, data->dFdV[block_ij].m, dfdv);
+}
+
+bool BPH_mass_spring_force_spring_linear(Implicit_Data *data,
+                                         int i,
+                                         int j,
+                                         float restlen,
+                                         float stiffness_tension,
+                                         float damping_tension,
+                                         float stiffness_compression,
+                                         float damping_compression,
+                                         bool resist_compress,
+                                         bool new_compress,
+                                         float clamp_force)
+{
+  float extent[3], length, dir[3], vel[3];
+  float f[3], dfdx[3][3], dfdv[3][3];
+  float damping = 0;
+
+  // calculate elonglation
+  spring_length(data, i, j, extent, dir, &length, vel);
+
+  /* This code computes not only the force, but also its derivative.
+     Zero derivative effectively disables the spring for the implicit solver.
+     Thus length > restlen makes cloth unconstrained at the start of simulation. */
+  if ((length >= restlen && length > 0) || resist_compress) {
+    float stretch_force;
+
+    damping = damping_tension;
+
+    stretch_force = stiffness_tension * (length - restlen);
+    if (clamp_force > 0.0f && stretch_force > clamp_force) {
+      stretch_force = clamp_force;
+    }
+    mul_v3_v3fl(f, dir, stretch_force);
+
+    dfdx_spring(dfdx, dir, length, restlen, stiffness_tension);
+  }
+  else if (new_compress) {
+    /* This is based on the Choi and Ko bending model, which works surprisingly well for compression. */
+    float kb = stiffness_compression;
+    float cb = kb; /* cb equal to kb seems to work, but a factor can be added if necessary */
+
+    damping = damping_compression;
+
+    mul_v3_v3fl(f, dir, fbstar(length, restlen, kb, cb));
+
+    outerproduct(dfdx, dir, dir);
+    mul_m3_fl(dfdx, fbstar_jacobi(length, restlen, kb, cb));
+  }
+  else {
+    return false;
+  }
+
+  madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
+  dfdv_damp(dfdv, dir, damping);
+
+  apply_spring(data, i, j, f, dfdx, dfdv);
+
+  return true;
 }
 
 /* See "Stable but Responsive Cloth" (Choi, Ko 2005) */
-bool BPH_mass_spring_force_spring_bending(Implicit_Data *data, int i, int j, float restlen, float kb, float cb)
+bool BPH_mass_spring_force_spring_bending(
+    Implicit_Data *data, int i, int j, float restlen, float kb, float cb)
 {
-	float extent[3], length, dir[3], vel[3];
+  float extent[3], length, dir[3], vel[3];
 
-	// calculate elonglation
-	spring_length(data, i, j, extent, dir, &length, vel);
+  // calculate elonglation
+  spring_length(data, i, j, extent, dir, &length, vel);
 
-	if (length < restlen) {
-		float f[3], dfdx[3][3], dfdv[3][3];
+  if (length < restlen) {
+    float f[3], dfdx[3][3], dfdv[3][3];
 
-		mul_v3_v3fl(f, dir, fbstar(length, restlen, kb, cb));
+    mul_v3_v3fl(f, dir, fbstar(length, restlen, kb, cb));
 
-		outerproduct(dfdx, dir, dir);
-		mul_m3_fl(dfdx, fbstar_jacobi(length, restlen, kb, cb));
+    outerproduct(dfdx, dir, dir);
+    mul_m3_fl(dfdx, fbstar_jacobi(length, restlen, kb, cb));
 
-		/* XXX damping not supported */
-		zero_m3(dfdv);
+    /* XXX damping not supported */
+    zero_m3(dfdv);
 
-		apply_spring(data, i, j, f, dfdx, dfdv);
+    apply_spring(data, i, j, f, dfdx, dfdv);
 
-		return true;
-	}
-	else {
-		return false;
-	}
+    return true;
+  }
+  else {
+    return false;
+  }
 }
 
 BLI_INLINE void poly_avg(lfVector *data, int *inds, int len, float r_avg[3])
 {
-	float fact = 1.0f / (float)len;
+  float fact = 1.0f / (float)len;
 
-	zero_v3(r_avg);
+  zero_v3(r_avg);
 
-	for (int i = 0; i < len; i++) {
-		madd_v3_v3fl(r_avg, data[inds[i]], fact);
-	}
+  for (int i = 0; i < len; i++) {
+    madd_v3_v3fl(r_avg, data[inds[i]], fact);
+  }
 }
 
 BLI_INLINE void poly_norm(lfVector *data, int i, int j, int *inds, int len, float r_dir[3])
 {
-	float mid[3];
+  float mid[3];
 
-	poly_avg(data, inds, len, mid);
+  poly_avg(data, inds, len, mid);
 
-	normal_tri_v3(r_dir, data[i], data[j], mid);
+  normal_tri_v3(r_dir, data[i], data[j], mid);
 }
 
 BLI_INLINE void edge_avg(lfVector *data, int i, int j, float r_avg[3])
 {
-	r_avg[0] = (data[i][0] + data[j][0]) * 0.5f;
-	r_avg[1] = (data[i][1] + data[j][1]) * 0.5f;
-	r_avg[2] = (data[i][2] + data[j][2]) * 0.5f;
+  r_avg[0] = (data[i][0] + data[j][0]) * 0.5f;
+  r_avg[1] = (data[i][1] + data[j][1]) * 0.5f;
+  r_avg[2] = (data[i][2] + data[j][2]) * 0.5f;
 }
 
 BLI_INLINE void edge_norm(lfVector *data, int i, int j, float r_dir[3])
 {
-	sub_v3_v3v3(r_dir, data[i], data[j]);
-	normalize_v3(r_dir);
+  sub_v3_v3v3(r_dir, data[i], data[j]);
+  normalize_v3(r_dir);
 }
 
 BLI_INLINE float bend_angle(float dir_a[3], float dir_b[3], float dir_e[3])
 {
-	float cos, sin;
-	float tmp[3];
+  float cos, sin;
+  float tmp[3];
 
-	cos = dot_v3v3(dir_a, dir_b);
+  cos = dot_v3v3(dir_a, dir_b);
 
-	cross_v3_v3v3(tmp, dir_a, dir_b);
-	sin = dot_v3v3(tmp, dir_e);
+  cross_v3_v3v3(tmp, dir_a, dir_b);
+  sin = dot_v3v3(tmp, dir_e);
 
-	return atan2f(sin, cos);
+  return atan2f(sin, cos);
 }
 
-BLI_INLINE void spring_angle(Implicit_Data *data, int i, int j, int *i_a, int *i_b, int len_a, int len_b,
-                             float r_dir_a[3], float r_dir_b[3],
-                             float *r_angle, float r_vel_a[3], float r_vel_b[3])
+BLI_INLINE void spring_angle(Implicit_Data *data,
+                             int i,
+                             int j,
+                             int *i_a,
+                             int *i_b,
+                             int len_a,
+                             int len_b,
+                             float r_dir_a[3],
+                             float r_dir_b[3],
+                             float *r_angle,
+                             float r_vel_a[3],
+                             float r_vel_b[3])
 {
-	float dir_e[3], vel_e[3];
+  float dir_e[3], vel_e[3];
 
-	poly_norm(data->X, j, i, i_a, len_a, r_dir_a);
-	poly_norm(data->X, i, j, i_b, len_b, r_dir_b);
+  poly_norm(data->X, j, i, i_a, len_a, r_dir_a);
+  poly_norm(data->X, i, j, i_b, len_b, r_dir_b);
 
-	edge_norm(data->X, i, j, dir_e);
+  edge_norm(data->X, i, j, dir_e);
 
-	*r_angle = bend_angle(r_dir_a, r_dir_b, dir_e);
+  *r_angle = bend_angle(r_dir_a, r_dir_b, dir_e);
 
-	poly_avg(data->V, i_a, len_a, r_vel_a);
-	poly_avg(data->V, i_b, len_b, r_vel_b);
+  poly_avg(data->V, i_a, len_a, r_vel_a);
+  poly_avg(data->V, i_b, len_b, r_vel_b);
 
-	edge_avg(data->V, i, j, vel_e);
+  edge_avg(data->V, i, j, vel_e);
 
-	sub_v3_v3(r_vel_a, vel_e);
-	sub_v3_v3(r_vel_b, vel_e);
+  sub_v3_v3(r_vel_a, vel_e);
+  sub_v3_v3(r_vel_b, vel_e);
 }
 
 /* Angular springs roughly based on the bending model proposed by Baraff and Witkin in "Large Steps in Cloth Simulation". */
-bool BPH_mass_spring_force_spring_angular(Implicit_Data *data, int i, int j, int *i_a, int *i_b, int len_a, int len_b,
-                                          float restang, float stiffness, float damping)
+bool BPH_mass_spring_force_spring_angular(Implicit_Data *data,
+                                          int i,
+                                          int j,
+                                          int *i_a,
+                                          int *i_b,
+                                          int len_a,
+                                          int len_b,
+                                          float restang,
+                                          float stiffness,
+                                          float damping)
 {
-	float angle, dir_a[3], dir_b[3], vel_a[3], vel_b[3];
-	float f_a[3], f_b[3], f_e[3];
-	float force;
-	int x;
+  float angle, dir_a[3], dir_b[3], vel_a[3], vel_b[3];
+  float f_a[3], f_b[3], f_e[3];
+  float force;
+  int x;
 
-	spring_angle(data, i, j, i_a, i_b, len_a, len_b,
-	             dir_a, dir_b, &angle, vel_a, vel_b);
+  spring_angle(data, i, j, i_a, i_b, len_a, len_b, dir_a, dir_b, &angle, vel_a, vel_b);
 
-	/* spring force */
-	force = stiffness * (angle - restang);
+  /* spring force */
+  force = stiffness * (angle - restang);
 
-	/* damping force */
-	force += -damping * (dot_v3v3(vel_a, dir_a) + dot_v3v3(vel_b, dir_b));
+  /* damping force */
+  force += -damping * (dot_v3v3(vel_a, dir_a) + dot_v3v3(vel_b, dir_b));
 
-	mul_v3_v3fl(f_a, dir_a, force / len_a);
-	mul_v3_v3fl(f_b, dir_b, force / len_b);
+  mul_v3_v3fl(f_a, dir_a, force / len_a);
+  mul_v3_v3fl(f_b, dir_b, force / len_b);
 
-	for (x = 0; x < len_a; x++) {
-		add_v3_v3(data->F[i_a[x]], f_a);
-	}
+  for (x = 0; x < len_a; x++) {
+    add_v3_v3(data->F[i_a[x]], f_a);
+  }
 
-	for (x = 0; x < len_b; x++) {
-		add_v3_v3(data->F[i_b[x]], f_b);
-	}
+  for (x = 0; x < len_b; x++) {
+    add_v3_v3(data->F[i_b[x]], f_b);
+  }
 
-	mul_v3_v3fl(f_a, dir_a, force * 0.5f);
-	mul_v3_v3fl(f_b, dir_b, force * 0.5f);
+  mul_v3_v3fl(f_a, dir_a, force * 0.5f);
+  mul_v3_v3fl(f_b, dir_b, force * 0.5f);
 
-	add_v3_v3v3(f_e, f_a, f_b);
+  add_v3_v3v3(f_e, f_a, f_b);
 
-	sub_v3_v3(data->F[i], f_e);
-	sub_v3_v3(data->F[j], f_e);
+  sub_v3_v3(data->F[i], f_e);
+  sub_v3_v3(data->F[j], f_e);
 
-	return true;
+  return true;
 }
 
 /* Jacobian of a direction vector.
@@ -1764,316 +1870,353 @@ bool BPH_mass_spring_force_spring_angular(Implicit_Data *data, int i, int j, int
  *
  * dD_ij/dx_i = -dD_ij/dx_j = (D_ij * D_ij^T - I) / len_ij
  */
-BLI_INLINE void spring_grad_dir(Implicit_Data *data, int i, int j, float edge[3], float dir[3], float grad_dir[3][3])
+BLI_INLINE void spring_grad_dir(
+    Implicit_Data *data, int i, int j, float edge[3], float dir[3], float grad_dir[3][3])
 {
-	float length;
+  float length;
 
-	sub_v3_v3v3(edge, data->X[j], data->X[i]);
-	length = normalize_v3_v3(dir, edge);
+  sub_v3_v3v3(edge, data->X[j], data->X[i]);
+  length = normalize_v3_v3(dir, edge);
 
-	if (length > ALMOST_ZERO) {
-		outerproduct(grad_dir, dir, dir);
-		sub_m3_m3m3(grad_dir, I, grad_dir);
-		mul_m3_fl(grad_dir, 1.0f / length);
-	}
-	else {
-		zero_m3(grad_dir);
-	}
+  if (length > ALMOST_ZERO) {
+    outerproduct(grad_dir, dir, dir);
+    sub_m3_m3m3(grad_dir, I, grad_dir);
+    mul_m3_fl(grad_dir, 1.0f / length);
+  }
+  else {
+    zero_m3(grad_dir);
+  }
 }
 
-BLI_INLINE void spring_hairbend_forces(Implicit_Data *data, int i, int j, int k,
+BLI_INLINE void spring_hairbend_forces(Implicit_Data *data,
+                                       int i,
+                                       int j,
+                                       int k,
                                        const float goal[3],
-                                       float stiffness, float damping,
-                                       int q, const float dx[3], const float dv[3],
+                                       float stiffness,
+                                       float damping,
+                                       int q,
+                                       const float dx[3],
+                                       const float dv[3],
                                        float r_f[3])
 {
-	float edge_ij[3], dir_ij[3];
-	float edge_jk[3], dir_jk[3];
-	float vel_ij[3], vel_jk[3], vel_ortho[3];
-	float f_bend[3], f_damp[3];
-	float fk[3];
-	float dist[3];
+  float edge_ij[3], dir_ij[3];
+  float edge_jk[3], dir_jk[3];
+  float vel_ij[3], vel_jk[3], vel_ortho[3];
+  float f_bend[3], f_damp[3];
+  float fk[3];
+  float dist[3];
 
-	zero_v3(fk);
+  zero_v3(fk);
 
-	sub_v3_v3v3(edge_ij, data->X[j], data->X[i]);
-	if (q == i) sub_v3_v3(edge_ij, dx);
-	if (q == j) add_v3_v3(edge_ij, dx);
-	normalize_v3_v3(dir_ij, edge_ij);
+  sub_v3_v3v3(edge_ij, data->X[j], data->X[i]);
+  if (q == i)
+    sub_v3_v3(edge_ij, dx);
+  if (q == j)
+    add_v3_v3(edge_ij, dx);
+  normalize_v3_v3(dir_ij, edge_ij);
 
-	sub_v3_v3v3(edge_jk, data->X[k], data->X[j]);
-	if (q == j) sub_v3_v3(edge_jk, dx);
-	if (q == k) add_v3_v3(edge_jk, dx);
-	normalize_v3_v3(dir_jk, edge_jk);
+  sub_v3_v3v3(edge_jk, data->X[k], data->X[j]);
+  if (q == j)
+    sub_v3_v3(edge_jk, dx);
+  if (q == k)
+    add_v3_v3(edge_jk, dx);
+  normalize_v3_v3(dir_jk, edge_jk);
 
-	sub_v3_v3v3(vel_ij, data->V[j], data->V[i]);
-	if (q == i) sub_v3_v3(vel_ij, dv);
-	if (q == j) add_v3_v3(vel_ij, dv);
+  sub_v3_v3v3(vel_ij, data->V[j], data->V[i]);
+  if (q == i)
+    sub_v3_v3(vel_ij, dv);
+  if (q == j)
+    add_v3_v3(vel_ij, dv);
 
-	sub_v3_v3v3(vel_jk, data->V[k], data->V[j]);
-	if (q == j) sub_v3_v3(vel_jk, dv);
-	if (q == k) add_v3_v3(vel_jk, dv);
+  sub_v3_v3v3(vel_jk, data->V[k], data->V[j]);
+  if (q == j)
+    sub_v3_v3(vel_jk, dv);
+  if (q == k)
+    add_v3_v3(vel_jk, dv);
 
-	/* bending force */
-	sub_v3_v3v3(dist, goal, edge_jk);
-	mul_v3_v3fl(f_bend, dist, stiffness);
+  /* bending force */
+  sub_v3_v3v3(dist, goal, edge_jk);
+  mul_v3_v3fl(f_bend, dist, stiffness);
 
-	add_v3_v3(fk, f_bend);
+  add_v3_v3(fk, f_bend);
 
-	/* damping force */
-	madd_v3_v3v3fl(vel_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
-	mul_v3_v3fl(f_damp, vel_ortho, damping);
+  /* damping force */
+  madd_v3_v3v3fl(vel_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
+  mul_v3_v3fl(f_damp, vel_ortho, damping);
 
-	sub_v3_v3(fk, f_damp);
+  sub_v3_v3(fk, f_damp);
 
-	copy_v3_v3(r_f, fk);
+  copy_v3_v3(r_f, fk);
 }
 
 /* Finite Differences method for estimating the jacobian of the force */
-BLI_INLINE void spring_hairbend_estimate_dfdx(Implicit_Data *data, int i, int j, int k,
+BLI_INLINE void spring_hairbend_estimate_dfdx(Implicit_Data *data,
+                                              int i,
+                                              int j,
+                                              int k,
                                               const float goal[3],
-                                              float stiffness, float damping,
-                                              int q, float dfdx[3][3])
+                                              float stiffness,
+                                              float damping,
+                                              int q,
+                                              float dfdx[3][3])
 {
-	const float delta = 0.00001f; // TODO find a good heuristic for this
-	float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
-	float f[3];
-	int a, b;
+  const float delta = 0.00001f;  // TODO find a good heuristic for this
+  float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
+  float f[3];
+  int a, b;
 
-	zero_m3(dvec_null);
-	unit_m3(dvec_pos);
-	mul_m3_fl(dvec_pos, delta * 0.5f);
-	copy_m3_m3(dvec_neg, dvec_pos);
-	negate_m3(dvec_neg);
+  zero_m3(dvec_null);
+  unit_m3(dvec_pos);
+  mul_m3_fl(dvec_pos, delta * 0.5f);
+  copy_m3_m3(dvec_neg, dvec_pos);
+  negate_m3(dvec_neg);
 
-	/* XXX TODO offset targets to account for position dependency */
+  /* XXX TODO offset targets to account for position dependency */
 
-	for (a = 0; a < 3; ++a) {
-		spring_hairbend_forces(data, i, j, k, goal, stiffness, damping,
-		                       q, dvec_pos[a], dvec_null[a], f);
-		copy_v3_v3(dfdx[a], f);
+  for (a = 0; a < 3; ++a) {
+    spring_hairbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_pos[a], dvec_null[a], f);
+    copy_v3_v3(dfdx[a], f);
 
-		spring_hairbend_forces(data, i, j, k, goal, stiffness, damping,
-		                       q, dvec_neg[a], dvec_null[a], f);
-		sub_v3_v3(dfdx[a], f);
+    spring_hairbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_neg[a], dvec_null[a], f);
+    sub_v3_v3(dfdx[a], f);
 
-		for (b = 0; b < 3; ++b) {
-			dfdx[a][b] /= delta;
-		}
-	}
+    for (b = 0; b < 3; ++b) {
+      dfdx[a][b] /= delta;
+    }
+  }
 }
 
 /* Finite Differences method for estimating the jacobian of the force */
-BLI_INLINE void spring_hairbend_estimate_dfdv(Implicit_Data *data, int i, int j, int k,
+BLI_INLINE void spring_hairbend_estimate_dfdv(Implicit_Data *data,
+                                              int i,
+                                              int j,
+                                              int k,
                                               const float goal[3],
-                                              float stiffness, float damping,
-                                              int q, float dfdv[3][3])
+                                              float stiffness,
+                                              float damping,
+                                              int q,
+                                              float dfdv[3][3])
 {
-	const float delta = 0.00001f; // TODO find a good heuristic for this
-	float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
-	float f[3];
-	int a, b;
+  const float delta = 0.00001f;  // TODO find a good heuristic for this
+  float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
+  float f[3];
+  int a, b;
 
-	zero_m3(dvec_null);
-	unit_m3(dvec_pos);
-	mul_m3_fl(dvec_pos, delta * 0.5f);
-	copy_m3_m3(dvec_neg, dvec_pos);
-	negate_m3(dvec_neg);
+  zero_m3(dvec_null);
+  unit_m3(dvec_pos);
+  mul_m3_fl(dvec_pos, delta * 0.5f);
+  copy_m3_m3(dvec_neg, dvec_pos);
+  negate_m3(dvec_neg);
 
-	/* XXX TODO offset targets to account for position dependency */
+  /* XXX TODO offset targets to account for position dependency */
 
-	for (a = 0; a < 3; ++a) {
-		spring_hairbend_forces(data, i, j, k, goal, stiffness, damping,
-		                       q, dvec_null[a], dvec_pos[a], f);
-		copy_v3_v3(dfdv[a], f);
+  for (a = 0; a < 3; ++a) {
+    spring_hairbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_null[a], dvec_pos[a], f);
+    copy_v3_v3(dfdv[a], f);
 
-		spring_hairbend_forces(data, i, j, k, goal, stiffness, damping,
-		                       q, dvec_null[a], dvec_neg[a], f);
-		sub_v3_v3(dfdv[a], f);
+    spring_hairbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_null[a], dvec_neg[a], f);
+    sub_v3_v3(dfdv[a], f);
 
-		for (b = 0; b < 3; ++b) {
-			dfdv[a][b] /= delta;
-		}
-	}
+    for (b = 0; b < 3; ++b) {
+      dfdv[a][b] /= delta;
+    }
+  }
 }
 
 /* Angular spring that pulls the vertex toward the local target
  * See "Artistic Simulation of Curly Hair" (Pixar technical memo #12-03a)
  */
-bool BPH_mass_spring_force_spring_bending_hair(Implicit_Data *data, int i, int j, int k,
-                                               const float target[3], float stiffness, float damping)
-{
-	float goal[3];
-	float fj[3], fk[3];
-	float dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
-	float dfj_dvi[3][3], dfj_dvj[3][3], dfk_dvi[3][3], dfk_dvj[3][3], dfk_dvk[3][3];
-
-	const float vecnull[3] = {0.0f, 0.0f, 0.0f};
-
-	int block_ij = BPH_mass_spring_add_block(data, i, j);
-	int block_jk = BPH_mass_spring_add_block(data, j, k);
-	int block_ik = BPH_mass_spring_add_block(data, i, k);
-
-	world_to_root_v3(data, j, goal, target);
-
-	spring_hairbend_forces(data, i, j, k, goal, stiffness, damping, k, vecnull, vecnull, fk);
-	negate_v3_v3(fj, fk); /* counterforce */
-
-	spring_hairbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, i, dfk_dxi);
-	spring_hairbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, j, dfk_dxj);
-	spring_hairbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, k, dfk_dxk);
-	copy_m3_m3(dfj_dxi, dfk_dxi); negate_m3(dfj_dxi);
-	copy_m3_m3(dfj_dxj, dfk_dxj); negate_m3(dfj_dxj);
-
-	spring_hairbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, i, dfk_dvi);
-	spring_hairbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, j, dfk_dvj);
-	spring_hairbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, k, dfk_dvk);
-	copy_m3_m3(dfj_dvi, dfk_dvi); negate_m3(dfj_dvi);
-	copy_m3_m3(dfj_dvj, dfk_dvj); negate_m3(dfj_dvj);
-
-	/* add forces and jacobians to the solver data */
-
-	add_v3_v3(data->F[j], fj);
-	add_v3_v3(data->F[k], fk);
-
-	add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfj_dxj);
-	add_m3_m3m3(data->dFdX[k].m, data->dFdX[k].m, dfk_dxk);
-
-	add_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfj_dxi);
-	add_m3_m3m3(data->dFdX[block_jk].m, data->dFdX[block_jk].m, dfk_dxj);
-	add_m3_m3m3(data->dFdX[block_ik].m, data->dFdX[block_ik].m, dfk_dxi);
-
-	add_m3_m3m3(data->dFdV[j].m, data->dFdV[j].m, dfj_dvj);
-	add_m3_m3m3(data->dFdV[k].m, data->dFdV[k].m, dfk_dvk);
-
-	add_m3_m3m3(data->dFdV[block_ij].m, data->dFdV[block_ij].m, dfj_dvi);
-	add_m3_m3m3(data->dFdV[block_jk].m, data->dFdV[block_jk].m, dfk_dvj);
-	add_m3_m3m3(data->dFdV[block_ik].m, data->dFdV[block_ik].m, dfk_dvi);
-
-
-	/* XXX analytical calculation of derivatives below is incorrect.
-	 * This proved to be difficult, but for now just using the finite difference method for
-	 * estimating the jacobians should be sufficient.
-	 */
-#if 0
-	float edge_ij[3], dir_ij[3], grad_dir_ij[3][3];
-	float edge_jk[3], dir_jk[3], grad_dir_jk[3][3];
-	float dist[3], vel_jk[3], vel_jk_ortho[3], projvel[3];
-	float target[3];
-	float tmp[3][3];
-	float fi[3], fj[3], fk[3];
-	float dfi_dxi[3][3], dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
-	float dfdvi[3][3];
-
-	// TESTING
-	damping = 0.0f;
-
-	zero_v3(fi);
-	zero_v3(fj);
-	zero_v3(fk);
-	zero_m3(dfi_dxi);
-	zero_m3(dfj_dxi);
-	zero_m3(dfk_dxi);
-	zero_m3(dfk_dxj);
-	zero_m3(dfk_dxk);
-
-	/* jacobian of direction vectors */
-	spring_grad_dir(data, i, j, edge_ij, dir_ij, grad_dir_ij);
-	spring_grad_dir(data, j, k, edge_jk, dir_jk, grad_dir_jk);
-
-	sub_v3_v3v3(vel_jk, data->V[k], data->V[j]);
-
-	/* bending force */
-	mul_v3_v3fl(target, dir_ij, restlen);
-	sub_v3_v3v3(dist, target, edge_jk);
-	mul_v3_v3fl(fk, dist, stiffness);
-
-	/* damping force */
-	madd_v3_v3v3fl(vel_jk_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
-	madd_v3_v3fl(fk, vel_jk_ortho, damping);
-
-	/* XXX this only holds true as long as we assume straight rest shape!
-	 * eventually will become a bit more involved since the opposite segment
-	 * gets its own target, under condition of having equal torque on both sides.
-	 */
-	copy_v3_v3(fi, fk);
-
-	/* counterforce on the middle point */
-	sub_v3_v3(fj, fi);
-	sub_v3_v3(fj, fk);
-
-	/* === derivatives === */
-
-	madd_m3_m3fl(dfk_dxi, grad_dir_ij, stiffness * restlen);
-
-	madd_m3_m3fl(dfk_dxj, grad_dir_ij, -stiffness * restlen);
-	madd_m3_m3fl(dfk_dxj, I, stiffness);
-
-	madd_m3_m3fl(dfk_dxk, I, -stiffness);
-
-	copy_m3_m3(dfi_dxi, dfk_dxk);
-	negate_m3(dfi_dxi);
-
-	/* dfj_dfi == dfi_dfj due to symmetry,
-	 * dfi_dfj == dfk_dfj due to fi == fk
-	 * XXX see comment above on future bent rest shapes
-	 */
-	copy_m3_m3(dfj_dxi, dfk_dxj);
-
-	/* dfj_dxj == -(dfi_dxj + dfk_dxj) due to fj == -(fi + fk) */
-	sub_m3_m3m3(dfj_dxj, dfj_dxj, dfj_dxi);
-	sub_m3_m3m3(dfj_dxj, dfj_dxj, dfk_dxj);
-
-	/* add forces and jacobians to the solver data */
-	add_v3_v3(data->F[i], fi);
-	add_v3_v3(data->F[j], fj);
-	add_v3_v3(data->F[k], fk);
-
-	add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfi_dxi);
-	add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfj_dxj);
-	add_m3_m3m3(data->dFdX[k].m, data->dFdX[k].m, dfk_dxk);
-
-	add_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfj_dxi);
-	add_m3_m3m3(data->dFdX[block_jk].m, data->dFdX[block_jk].m, dfk_dxj);
-	add_m3_m3m3(data->dFdX[block_ik].m, data->dFdX[block_ik].m, dfk_dxi);
-#endif
-
-	return true;
-}
-
-bool BPH_mass_spring_force_spring_goal(Implicit_Data *data, int i, const float goal_x[3], const float goal_v[3],
-                                       float stiffness, float damping)
-{
-	float root_goal_x[3], root_goal_v[3], extent[3], length, dir[3], vel[3];
-	float f[3], dfdx[3][3], dfdv[3][3];
-
-	/* goal is in world space */
-	world_to_root_v3(data, i, root_goal_x, goal_x);
-	world_to_root_v3(data, i, root_goal_v, goal_v);
-
-	sub_v3_v3v3(extent, root_goal_x, data->X[i]);
-	sub_v3_v3v3(vel, root_goal_v, data->V[i]);
-	length = normalize_v3_v3(dir, extent);
-
-	if (length > ALMOST_ZERO) {
-		mul_v3_v3fl(f, dir, stiffness * length);
+bool BPH_mass_spring_force_spring_bending_hair(Implicit_Data *data,
+                                               int i,
+                                               int j,
+                                               int k,
+                                               const float target[3],
+                                               float stiffness,
+                                               float damping)
+{
+  float goal[3];
+  float fj[3], fk[3];
+  float dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
+  float dfj_dvi[3][3], dfj_dvj[3][3], dfk_dvi[3][3], dfk_dvj[3][3], dfk_dvk[3][3];
+
+  const float vecnull[3] = {0.0f, 0.0f, 0.0f};
+
+  int block_ij = BPH_mass_spring_add_block(data, i, j);
+  int block_jk = BPH_mass_spring_add_block(data, j, k);
+  int block_ik = BPH_mass_spring_add_block(data, i, k);
+
+  world_to_root_v3(data, j, goal, target);
+
+  spring_hairbend_forces(data, i, j, k, goal, stiffness, damping, k, vecnull, vecnull, fk);
+  negate_v3_v3(fj, fk); /* counterforce */
+
+  spring_hairbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, i, dfk_dxi);
+  spring_hairbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, j, dfk_dxj);
+  spring_hairbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, k, dfk_dxk);
+  copy_m3_m3(dfj_dxi, dfk_dxi);
+  negate_m3(dfj_dxi);
+  copy_m3_m3(dfj_dxj, dfk_dxj);
+  negate_m3(dfj_dxj);
+
+  spring_hairbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, i, dfk_dvi);
+  spring_hairbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, j, dfk_dvj);
+  spring_hairbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, k, dfk_dvk);
+  copy_m3_m3(dfj_dvi, dfk_dvi);
+  negate_m3(dfj_dvi);
+  copy_m3_m3(dfj_dvj, dfk_dvj);
+  negate_m3(dfj_dvj);
+
+  /* add forces and jacobians to the solver data */
+
+  add_v3_v3(data->F[j], fj);
+  add_v3_v3(data->F[k], fk);
+
+  add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfj_dxj);
+  add_m3_m3m3(data->dFdX[k].m, data->dFdX[k].m, dfk_dxk);
+
+  add_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfj_dxi);
+  add_m3_m3m3(data->dFdX[block_jk].m, data->dFdX[block_jk].m, dfk_dxj);
+  add_m3_m3m3(data->dFdX[block_ik].m, data->dFdX[block_ik].m, dfk_dxi);
+
+  add_m3_m3m3(data->dFdV[j].m, data->dFdV[j].m, dfj_dvj);
+  add_m3_m3m3(data->dFdV[k].m, data->dFdV[k].m, dfk_dvk);
+
+  add_m3_m3m3(data->dFdV[block_ij].m, data->dFdV[block_ij].m, dfj_dvi);
+  add_m3_m3m3(data->dFdV[block_jk].m, data->dFdV[block_jk].m, dfk_dvj);
+  add_m3_m3m3(data->dFdV[block_ik].m, data->dFdV[block_ik].m, dfk_dvi);
+
+  /* XXX analytical calculation of derivatives below is incorrect.
+   * This proved to be difficult, but for now just using the finite difference method for
+   * estimating the jacobians should be sufficient.
+   */
+#  if 0
+  float edge_ij[3], dir_ij[3], grad_dir_ij[3][3];
+  float edge_jk[3], dir_jk[3], grad_dir_jk[3][3];
+  float dist[3], vel_jk[3], vel_jk_ortho[3], projvel[3];
+  float target[3];
+  float tmp[3][3];
+  float fi[3], fj[3], fk[3];
+  float dfi_dxi[3][3], dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
+  float dfdvi[3][3];
+
+  // TESTING
+  damping = 0.0f;
+
+  zero_v3(fi);
+  zero_v3(fj);
+  zero_v3(fk);
+  zero_m3(dfi_dxi);
+  zero_m3(dfj_dxi);
+  zero_m3(dfk_dxi);
+  zero_m3(dfk_dxj);
+  zero_m3(dfk_dxk);
+
+  /* jacobian of direction vectors */
+  spring_grad_dir(data, i, j, edge_ij, dir_ij, grad_dir_ij);
+  spring_grad_dir(data, j, k, edge_jk, dir_jk, grad_dir_jk);
+
+  sub_v3_v3v3(vel_jk, data->V[k], data->V[j]);
+
+  /* bending force */
+  mul_v3_v3fl(target, dir_ij, restlen);
+  sub_v3_v3v3(dist, target, edge_jk);
+  mul_v3_v3fl(fk, dist, stiffness);
+
+  /* damping force */
+  madd_v3_v3v3fl(vel_jk_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
+  madd_v3_v3fl(fk, vel_jk_ortho, damping);
+
+  /* XXX this only holds true as long as we assume straight rest shape!
+   * eventually will become a bit more involved since the opposite segment
+   * gets its own target, under condition of having equal torque on both sides.
+   */
+  copy_v3_v3(fi, fk);
+
+  /* counterforce on the middle point */
+  sub_v3_v3(fj, fi);
+  sub_v3_v3(fj, fk);
+
+  /* === derivatives === */
+
+  madd_m3_m3fl(dfk_dxi, grad_dir_ij, stiffness * restlen);
+
+  madd_m3_m3fl(dfk_dxj, grad_dir_ij, -stiffness * restlen);
+  madd_m3_m3fl(dfk_dxj, I, stiffness);
+
+  madd_m3_m3fl(dfk_dxk, I, -stiffness);
+
+  copy_m3_m3(dfi_dxi, dfk_dxk);
+  negate_m3(dfi_dxi);
+
+  /* dfj_dfi == dfi_dfj due to symmetry,
+   * dfi_dfj == dfk_dfj due to fi == fk
+   * XXX see comment above on future bent rest shapes
+   */
+  copy_m3_m3(dfj_dxi, dfk_dxj);
+
+  /* dfj_dxj == -(dfi_dxj + dfk_dxj) due to fj == -(fi + fk) */
+  sub_m3_m3m3(dfj_dxj, dfj_dxj, dfj_dxi);
+  sub_m3_m3m3(dfj_dxj, dfj_dxj, dfk_dxj);
+
+  /* add forces and jacobians to the solver data */
+  add_v3_v3(data->F[i], fi);
+  add_v3_v3(data->F[j], fj);
+  add_v3_v3(data->F[k], fk);
+
+  add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfi_dxi);
+  add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfj_dxj);
+  add_m3_m3m3(data->dFdX[k].m, data->dFdX[k].m, dfk_dxk);
+
+  add_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfj_dxi);
+  add_m3_m3m3(data->dFdX[block_jk].m, data->dFdX[block_jk].m, dfk_dxj);
+  add_m3_m3m3(data->dFdX[block_ik].m, data->dFdX[block_ik].m, dfk_dxi);
+#  endif
+
+  return true;
+}
+
+bool BPH_mass_spring_force_spring_goal(Implicit_Data *data,
+                                       int i,
+                                       const float goal_x[3],
+                                       const float goal_v[3],
+                                       float stiffness,
+                                       float damping)
+{
+  float root_goal_x[3], root_goal_v[3], extent[3], length, dir[3], vel[3];
+  float f[3], dfdx[3][3], dfdv[3][3];
+
+  /* goal is in world space */
+  world_to_root_v3(data, i, root_goal_x, goal_x);
+  world_to_root_v3(data, i, root_goal_v, goal_v);
+
+  sub_v3_v3v3(extent, root_goal_x, data->X[i]);
+  sub_v3_v3v3(vel, root_goal_v, data->V[i]);
+  length = normalize_v3_v3(dir, extent);
+
+  if (length > ALMOST_ZERO) {
+    mul_v3_v3fl(f, dir, stiffness * length);
 
-		// Ascher & Boxman, p.21: Damping only during elonglation
-		// something wrong with it...
-		madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
+    // Ascher & Boxman, p.21: Damping only during elonglation
+    // something wrong with it...
+    madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
 
-		dfdx_spring(dfdx, dir, length, 0.0f, stiffness);
-		dfdv_damp(dfdv, dir, damping);
+    dfdx_spring(dfdx, dir, length, 0.0f, stiffness);
+    dfdv_damp(dfdv, dir, damping);
 
-		add_v3_v3(data->F[i], f);
-		add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfdx);
-		add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, dfdv);
+    add_v3_v3(data->F[i], f);
+    add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfdx);
+    add_m3_m3m3(data->dFdV[i].m, data->dFdV[i].m, dfdv);
 
-		return true;
-	}
-	else {
-		return false;
-	}
+    return true;
+  }
+  else {
+    return false;
+  }
 }
 
 #endif /* IMPLICIT_SOLVER_BLENDER */
diff --git a/source/blender/physics/intern/implicit_eigen.cpp b/source/blender/physics/intern/implicit_eigen.cpp
index 5319042ec13..2b9761f0ccc 100644
--- a/source/blender/physics/intern/implicit_eigen.cpp
+++ b/source/blender/physics/intern/implicit_eigen.cpp
@@ -26,59 +26,59 @@
 #ifdef IMPLICIT_SOLVER_EIGEN
 
 //#define USE_EIGEN_CORE
-#define USE_EIGEN_CONSTRAINED_CG
+#  define USE_EIGEN_CONSTRAINED_CG
 
-#ifdef __GNUC__
-#  pragma GCC diagnostic push
+#  ifdef __GNUC__
+#    pragma GCC diagnostic push
 /* XXX suppress verbose warnings in eigen */
 //#  pragma GCC diagnostic ignored "-Wlogical-op"
-#endif
+#  endif
 
-#ifndef IMPLICIT_ENABLE_EIGEN_DEBUG
-#ifdef NDEBUG
-#define IMPLICIT_NDEBUG
-#endif
-#define NDEBUG
-#endif
+#  ifndef IMPLICIT_ENABLE_EIGEN_DEBUG
+#    ifdef NDEBUG
+#      define IMPLICIT_NDEBUG
+#    endif
+#    define NDEBUG
+#  endif
 
-#include <Eigen/Sparse>
-#include <Eigen/src/Core/util/DisableStupidWarnings.h>
+#  include <Eigen/Sparse>
+#  include <Eigen/src/Core/util/DisableStupidWarnings.h>
 
-#ifdef USE_EIGEN_CONSTRAINED_CG
-#include <intern/ConstrainedConjugateGradient.h>
-#endif
+#  ifdef USE_EIGEN_CONSTRAINED_CG
+#    include <intern/ConstrainedConjugateGradient.h>
+#  endif
 
-#ifndef IMPLICIT_ENABLE_EIGEN_DEBUG
-#ifndef IMPLICIT_NDEBUG
-#undef NDEBUG
-#else
-#undef IMPLICIT_NDEBUG
-#endif
-#endif
+#  ifndef IMPLICIT_ENABLE_EIGEN_DEBUG
+#    ifndef IMPLICIT_NDEBUG
+#      undef NDEBUG
+#    else
+#      undef IMPLICIT_NDEBUG
+#    endif
+#  endif
 
-#ifdef __GNUC__
-#  pragma GCC diagnostic pop
-#endif
+#  ifdef __GNUC__
+#    pragma GCC diagnostic pop
+#  endif
 
-#include "MEM_guardedalloc.h"
+#  include "MEM_guardedalloc.h"
 
 extern "C" {
-#include "DNA_scene_types.h"
-#include "DNA_object_types.h"
-#include "DNA_object_force_types.h"
-#include "DNA_meshdata_types.h"
-#include "DNA_texture_types.h"
+#  include "DNA_scene_types.h"
+#  include "DNA_object_types.h"
+#  include "DNA_object_force_types.h"
+#  include "DNA_meshdata_types.h"
+#  include "DNA_texture_types.h"
 
-#include "BLI_math.h"
-#include "BLI_linklist.h"
-#include "BLI_utildefines.h"
+#  include "BLI_math.h"
+#  include "BLI_linklist.h"
+#  include "BLI_utildefines.h"
 
-#include "BKE_cloth.h"
-#include "BKE_collision.h"
-#include "BKE_effect.h"
-#include "BKE_global.h"
+#  include "BKE_cloth.h"
+#  include "BKE_collision.h"
+#  include "BKE_effect.h"
+#  include "BKE_global.h"
 
-#include "BPH_mass_spring.h"
+#  include "BPH_mass_spring.h"
 }
 
 typedef float Scalar;
@@ -89,91 +89,90 @@ static float I[3][3] = {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}};
  * with conversion to/from plain C float array
  */
 class fVector : public Eigen::Vector3f {
-public:
-	typedef float *ctype;
-
-	fVector()
-	{
-	}
-
-	fVector(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			coeffRef(k) = v[k];
-	}
-
-	fVector& operator =(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			coeffRef(k) = v[k];
-		return *this;
-	}
-
-	operator ctype()
-	{
-		return data();
-	}
+ public:
+  typedef float *ctype;
+
+  fVector()
+  {
+  }
+
+  fVector(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      coeffRef(k) = v[k];
+  }
+
+  fVector &operator=(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      coeffRef(k) = v[k];
+    return *this;
+  }
+
+  operator ctype()
+  {
+    return data();
+  }
 };
 
 /* slightly extended Eigen matrix class
  * with conversion to/from plain C float array
  */
 class fMatrix : public Eigen::Matrix3f {
-public:
-	typedef float (*ctype)[3];
-
-	fMatrix()
-	{
-	}
-
-	fMatrix(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				coeffRef(l, k) = v[k][l];
-	}
-
-	fMatrix& operator =(const ctype &v)
-	{
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				coeffRef(l, k) = v[k][l];
-		return *this;
-	}
-
-	operator ctype()
-	{
-		return (ctype)data();
-	}
+ public:
+  typedef float (*ctype)[3];
+
+  fMatrix()
+  {
+  }
+
+  fMatrix(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        coeffRef(l, k) = v[k][l];
+  }
+
+  fMatrix &operator=(const ctype &v)
+  {
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        coeffRef(l, k) = v[k][l];
+    return *this;
+  }
+
+  operator ctype()
+  {
+    return (ctype)data();
+  }
 };
 
 /* Extension of dense Eigen vectors,
  * providing 3-float block access for blenlib math functions
  */
 class lVector : public Eigen::VectorXf {
-public:
-	typedef Eigen::VectorXf base_t;
-
-	lVector()
-	{
-	}
-
-	template <typename T>
-	lVector& operator =(T rhs)
-	{
-		base_t::operator=(rhs);
-		return *this;
-	}
-
-	float *v3(int vertex)
-	{
-		return &coeffRef(3 * vertex);
-	}
-
-	const float *v3(int vertex) const
-	{
-		return &coeffRef(3 * vertex);
-	}
+ public:
+  typedef Eigen::VectorXf base_t;
+
+  lVector()
+  {
+  }
+
+  template<typename T> lVector &operator=(T rhs)
+  {
+    base_t::operator=(rhs);
+    return *this;
+  }
+
+  float *v3(int vertex)
+  {
+    return &coeffRef(3 * vertex);
+  }
+
+  const float *v3(int vertex) const
+  {
+    return &coeffRef(3 * vertex);
+  }
 };
 
 typedef Eigen::Triplet<Scalar> Triplet;
@@ -187,825 +186,898 @@ typedef Eigen::SparseMatrix<Scalar> lMatrix;
  * After all elements have been defined using the set() method, the actual matrix can be filled using construct().
  */
 struct lMatrixCtor {
-	lMatrixCtor()
-	{
-	}
-
-	void reset()
-	{
-		m_trips.clear();
-	}
-
-	void reserve(int numverts)
-	{
-		/* reserve for diagonal entries */
-		m_trips.reserve(numverts * 9);
-	}
-
-	void add(int i, int j, const fMatrix &m)
-	{
-		i *= 3;
-		j *= 3;
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				m_trips.push_back(Triplet(i + k, j + l, m.coeff(l, k)));
-	}
-
-	void sub(int i, int j, const fMatrix &m)
-	{
-		i *= 3;
-		j *= 3;
-		for (int k = 0; k < 3; ++k)
-			for (int l = 0; l < 3; ++l)
-				m_trips.push_back(Triplet(i + k, j + l, -m.coeff(l, k)));
-	}
-
-	inline void construct(lMatrix &m)
-	{
-		m.setFromTriplets(m_trips.begin(), m_trips.end());
-		m_trips.clear();
-	}
-
-private:
-	TripletList m_trips;
+  lMatrixCtor()
+  {
+  }
+
+  void reset()
+  {
+    m_trips.clear();
+  }
+
+  void reserve(int numverts)
+  {
+    /* reserve for diagonal entries */
+    m_trips.reserve(numverts * 9);
+  }
+
+  void add(int i, int j, const fMatrix &m)
+  {
+    i *= 3;
+    j *= 3;
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        m_trips.push_back(Triplet(i + k, j + l, m.coeff(l, k)));
+  }
+
+  void sub(int i, int j, const fMatrix &m)
+  {
+    i *= 3;
+    j *= 3;
+    for (int k = 0; k < 3; ++k)
+      for (int l = 0; l < 3; ++l)
+        m_trips.push_back(Triplet(i + k, j + l, -m.coeff(l, k)));
+  }
+
+  inline void construct(lMatrix &m)
+  {
+    m.setFromTriplets(m_trips.begin(), m_trips.end());
+    m_trips.clear();
+  }
+
+ private:
+  TripletList m_trips;
 };
 
-#ifdef USE_EIGEN_CORE
-typedef Eigen::ConjugateGradient<lMatrix, Eigen::Lower, Eigen::DiagonalPreconditioner<Scalar> > ConjugateGradient;
-#endif
-#ifdef USE_EIGEN_CONSTRAINED_CG
-typedef Eigen::ConstrainedConjugateGradient<lMatrix, Eigen::Lower, lMatrix,
-                                            Eigen::DiagonalPreconditioner<Scalar> >
+#  ifdef USE_EIGEN_CORE
+typedef Eigen::ConjugateGradient<lMatrix, Eigen::Lower, Eigen::DiagonalPreconditioner<Scalar>>
+    ConjugateGradient;
+#  endif
+#  ifdef USE_EIGEN_CONSTRAINED_CG
+typedef Eigen::ConstrainedConjugateGradient<lMatrix,
+                                            Eigen::Lower,
+                                            lMatrix,
+                                            Eigen::DiagonalPreconditioner<Scalar>>
     ConstraintConjGrad;
-#endif
+#  endif
 using Eigen::ComputationInfo;
 
 static void print_lvector(const lVector &v)
 {
-	for (int i = 0; i < v.rows(); ++i) {
-		if (i > 0 && i % 3 == 0)
-			printf("\n");
+  for (int i = 0; i < v.rows(); ++i) {
+    if (i > 0 && i % 3 == 0)
+      printf("\n");
 
-		printf("%f,\n", v[i]);
-	}
+    printf("%f,\n", v[i]);
+  }
 }
 
 static void print_lmatrix(const lMatrix &m)
 {
-	for (int j = 0; j < m.rows(); ++j) {
-		if (j > 0 && j % 3 == 0)
-			printf("\n");
+  for (int j = 0; j < m.rows(); ++j) {
+    if (j > 0 && j % 3 == 0)
+      printf("\n");
 
-		for (int i = 0; i < m.cols(); ++i) {
-			if (i > 0 && i % 3 == 0)
-				printf("  ");
+    for (int i = 0; i < m.cols(); ++i) {
+      if (i > 0 && i % 3 == 0)
+        printf("  ");
 
-			implicit_print_matrix_elem(m.coeff(j, i));
-		}
-		printf("\n");
-	}
+      implicit_print_matrix_elem(m.coeff(j, i));
+    }
+    printf("\n");
+  }
 }
 
 BLI_INLINE void lMatrix_reserve_elems(lMatrix &m, int num)
 {
-	m.reserve(Eigen::VectorXi::Constant(m.cols(), num));
+  m.reserve(Eigen::VectorXi::Constant(m.cols(), num));
 }
 
 BLI_INLINE float *lVector_v3(lVector &v, int vertex)
 {
-	return v.data() + 3 * vertex;
+  return v.data() + 3 * vertex;
 }
 
 BLI_INLINE const float *lVector_v3(const lVector &v, int vertex)
 {
-	return v.data() + 3 * vertex;
+  return v.data() + 3 * vertex;
 }
 
-#if 0
+#  if 0
 BLI_INLINE void triplets_m3(TripletList &tlist, float m[3][3], int i, int j)
 {
-	i *= 3;
-	j *= 3;
-	for (int l = 0; l < 3; ++l) {
-		for (int k = 0; k < 3; ++k) {
-			tlist.push_back(Triplet(i + k, j + l, m[k][l]));
-		}
-	}
+  i *= 3;
+  j *= 3;
+  for (int l = 0; l < 3; ++l) {
+    for (int k = 0; k < 3; ++k) {
+      tlist.push_back(Triplet(i + k, j + l, m[k][l]));
+    }
+  }
 }
 
 BLI_INLINE void triplets_m3fl(TripletList &tlist, float m[3][3], int i, int j, float factor)
 {
-	i *= 3;
-	j *= 3;
-	for (int l = 0; l < 3; ++l) {
-		for (int k = 0; k < 3; ++k) {
-			tlist.push_back(Triplet(i + k, j + l, m[k][l] * factor));
-		}
-	}
+  i *= 3;
+  j *= 3;
+  for (int l = 0; l < 3; ++l) {
+    for (int k = 0; k < 3; ++k) {
+      tlist.push_back(Triplet(i + k, j + l, m[k][l] * factor));
+    }
+  }
 }
 
 BLI_INLINE void lMatrix_add_triplets(lMatrix &r, const TripletList &tlist)
 {
-	lMatrix t(r.rows(), r.cols());
-	t.setFromTriplets(tlist.begin(), tlist.end());
-	r += t;
+  lMatrix t(r.rows(), r.cols());
+  t.setFromTriplets(tlist.begin(), tlist.end());
+  r += t;
 }
 
 BLI_INLINE void lMatrix_madd_triplets(lMatrix &r, const TripletList &tlist, float f)
 {
-	lMatrix t(r.rows(), r.cols());
-	t.setFromTriplets(tlist.begin(), tlist.end());
-	r += f * t;
+  lMatrix t(r.rows(), r.cols());
+  t.setFromTriplets(tlist.begin(), tlist.end());
+  r += f * t;
 }
 
 BLI_INLINE void lMatrix_sub_triplets(lMatrix &r, const TripletList &tlist)
 {
-	lMatrix t(r.rows(), r.cols());
-	t.setFromTriplets(tlist.begin(), tlist.end());
-	r -= t;
+  lMatrix t(r.rows(), r.cols());
+  t.setFromTriplets(tlist.begin(), tlist.end());
+  r -= t;
 }
-#endif
+#  endif
 
 BLI_INLINE void outerproduct(float r[3][3], const float a[3], const float b[3])
 {
-	mul_v3_v3fl(r[0], a, b[0]);
-	mul_v3_v3fl(r[1], a, b[1]);
-	mul_v3_v3fl(r[2], a, b[2]);
+  mul_v3_v3fl(r[0], a, b[0]);
+  mul_v3_v3fl(r[1], a, b[1]);
+  mul_v3_v3fl(r[2], a, b[2]);
 }
 
 BLI_INLINE void cross_m3_v3m3(float r[3][3], const float v[3], float m[3][3])
 {
-	cross_v3_v3v3(r[0], v, m[0]);
-	cross_v3_v3v3(r[1], v, m[1]);
-	cross_v3_v3v3(r[2], v, m[2]);
+  cross_v3_v3v3(r[0], v, m[0]);
+  cross_v3_v3v3(r[1], v, m[1]);
+  cross_v3_v3v3(r[2], v, m[2]);
 }
 
 BLI_INLINE void cross_v3_identity(float r[3][3], const float v[3])
 {
-	r[0][0] = 0.0f;     r[1][0] = v[2];     r[2][0] = -v[1];
-	r[0][1] = -v[2];    r[1][1] = 0.0f;     r[2][1] = v[0];
-	r[0][2] = v[1];     r[1][2] = -v[0];    r[2][2] = 0.0f;
+  r[0][0] = 0.0f;
+  r[1][0] = v[2];
+  r[2][0] = -v[1];
+  r[0][1] = -v[2];
+  r[1][1] = 0.0f;
+  r[2][1] = v[0];
+  r[0][2] = v[1];
+  r[1][2] = -v[0];
+  r[2][2] = 0.0f;
 }
 
 BLI_INLINE void madd_m3_m3fl(float r[3][3], float m[3][3], float f)
 {
-	r[0][0] += m[0][0] * f;
-	r[0][1] += m[0][1] * f;
-	r[0][2] += m[0][2] * f;
-	r[1][0] += m[1][0] * f;
-	r[1][1] += m[1][1] * f;
-	r[1][2] += m[1][2] * f;
-	r[2][0] += m[2][0] * f;
-	r[2][1] += m[2][1] * f;
-	r[2][2] += m[2][2] * f;
+  r[0][0] += m[0][0] * f;
+  r[0][1] += m[0][1] * f;
+  r[0][2] += m[0][2] * f;
+  r[1][0] += m[1][0] * f;
+  r[1][1] += m[1][1] * f;
+  r[1][2] += m[1][2] * f;
+  r[2][0] += m[2][0] * f;
+  r[2][1] += m[2][1] * f;
+  r[2][2] += m[2][2] * f;
 }
 
 BLI_INLINE void madd_m3_m3m3fl(float r[3][3], float a[3][3], float b[3][3], float f)
 {
-	r[0][0] = a[0][0] + b[0][0] * f;
-	r[0][1] = a[0][1] + b[0][1] * f;
-	r[0][2] = a[0][2] + b[0][2] * f;
-	r[1][0] = a[1][0] + b[1][0] * f;
-	r[1][1] = a[1][1] + b[1][1] * f;
-	r[1][2] = a[1][2] + b[1][2] * f;
-	r[2][0] = a[2][0] + b[2][0] * f;
-	r[2][1] = a[2][1] + b[2][1] * f;
-	r[2][2] = a[2][2] + b[2][2] * f;
+  r[0][0] = a[0][0] + b[0][0] * f;
+  r[0][1] = a[0][1] + b[0][1] * f;
+  r[0][2] = a[0][2] + b[0][2] * f;
+  r[1][0] = a[1][0] + b[1][0] * f;
+  r[1][1] = a[1][1] + b[1][1] * f;
+  r[1][2] = a[1][2] + b[1][2] * f;
+  r[2][0] = a[2][0] + b[2][0] * f;
+  r[2][1] = a[2][1] + b[2][1] * f;
+  r[2][2] = a[2][2] + b[2][2] * f;
 }
 
 struct Implicit_Data {
-	typedef std::vector<fMatrix> fMatrixVector;
+  typedef std::vector<fMatrix> fMatrixVector;
 
-	Implicit_Data(int numverts)
-	{
-		resize(numverts);
-	}
+  Implicit_Data(int numverts)
+  {
+    resize(numverts);
+  }
 
-	void resize(int numverts)
-	{
-		this->numverts = numverts;
-		int tot = 3 * numverts;
+  void resize(int numverts)
+  {
+    this->numverts = numverts;
+    int tot = 3 * numverts;
 
-		M.resize(tot, tot);
-		F.resize(tot);
-		dFdX.resize(tot, tot);
-		dFdV.resize(tot, tot);
+    M.resize(tot, tot);
+    F.resize(tot);
+    dFdX.resize(tot, tot);
+    dFdV.resize(tot, tot);
 
-		tfm.resize(numverts, I);
+    tfm.resize(numverts, I);
 
-		X.resize(tot);
-		Xnew.resize(tot);
-		V.resize(tot);
-		Vnew.resize(tot);
+    X.resize(tot);
+    Xnew.resize(tot);
+    V.resize(tot);
+    Vnew.resize(tot);
 
-		A.resize(tot, tot);
-		B.resize(tot);
+    A.resize(tot, tot);
+    B.resize(tot);
 
-		dV.resize(tot);
-		z.resize(tot);
-		S.resize(tot, tot);
+    dV.resize(tot);
+    z.resize(tot);
+    S.resize(tot, tot);
 
-		iM.reserve(numverts);
-		idFdX.reserve(numverts);
-		idFdV.reserve(numverts);
-		iS.reserve(numverts);
-	}
+    iM.reserve(numverts);
+    idFdX.reserve(numverts);
+    idFdV.reserve(numverts);
+    iS.reserve(numverts);
+  }
 
-	int numverts;
+  int numverts;
 
-	/* inputs */
-	lMatrix M;                  /* masses */
-	lVector F;                  /* forces */
-	lMatrix dFdX, dFdV;         /* force jacobians */
+  /* inputs */
+  lMatrix M;          /* masses */
+  lVector F;          /* forces */
+  lMatrix dFdX, dFdV; /* force jacobians */
 
-	fMatrixVector tfm;          /* local coordinate transform */
+  fMatrixVector tfm; /* local coordinate transform */
 
-	/* motion state data */
-	lVector X, Xnew;            /* positions */
-	lVector V, Vnew;            /* velocities */
+  /* motion state data */
+  lVector X, Xnew; /* positions */
+  lVector V, Vnew; /* velocities */
 
-	/* internal solver data */
-	lVector B;                  /* B for A*dV = B */
-	lMatrix A;                  /* A for A*dV = B */
+  /* internal solver data */
+  lVector B; /* B for A*dV = B */
+  lMatrix A; /* A for A*dV = B */
 
-	lVector dV;                 /* velocity change (solution of A*dV = B) */
-	lVector z;                  /* target velocity in constrained directions */
-	lMatrix S;                  /* filtering matrix for constraints */
+  lVector dV; /* velocity change (solution of A*dV = B) */
+  lVector z;  /* target velocity in constrained directions */
+  lMatrix S;  /* filtering matrix for constraints */
 
-	/* temporary constructors */
-	lMatrixCtor iM;             /* masses */
-	lMatrixCtor idFdX, idFdV;   /* force jacobians */
-	lMatrixCtor iS;             /* filtering matrix for constraints */
+  /* temporary constructors */
+  lMatrixCtor iM;           /* masses */
+  lMatrixCtor idFdX, idFdV; /* force jacobians */
+  lMatrixCtor iS;           /* filtering matrix for constraints */
 };
 
 Implicit_Data *BPH_mass_spring_solver_create(int numverts, int numsprings)
 {
-	Implicit_Data *id = new Implicit_Data(numverts);
-	return id;
+  Implicit_Data *id = new Implicit_Data(numverts);
+  return id;
 }
 
 void BPH_mass_spring_solver_free(Implicit_Data *id)
 {
-	if (id)
-		delete id;
+  if (id)
+    delete id;
 }
 
 int BPH_mass_spring_solver_numvert(Implicit_Data *id)
 {
-	if (id)
-		return id->numverts;
-	else
-		return 0;
+  if (id)
+    return id->numverts;
+  else
+    return 0;
 }
 
 /* ==== Transformation from/to root reference frames ==== */
 
 BLI_INLINE void world_to_root_v3(Implicit_Data *data, int index, float r[3], const float v[3])
 {
-	copy_v3_v3(r, v);
-	mul_transposed_m3_v3(data->tfm[index], r);
+  copy_v3_v3(r, v);
+  mul_transposed_m3_v3(data->tfm[index], r);
 }
 
 BLI_INLINE void root_to_world_v3(Implicit_Data *data, int index, float r[3], const float v[3])
 {
-	mul_v3_m3v3(r, data->tfm[index], v);
+  mul_v3_m3v3(r, data->tfm[index], v);
 }
 
 BLI_INLINE void world_to_root_m3(Implicit_Data *data, int index, float r[3][3], float m[3][3])
 {
-	float trot[3][3];
-	copy_m3_m3(trot, data->tfm[index]);
-	transpose_m3(trot);
-	mul_m3_m3m3(r, trot, m);
+  float trot[3][3];
+  copy_m3_m3(trot, data->tfm[index]);
+  transpose_m3(trot);
+  mul_m3_m3m3(r, trot, m);
 }
 
 BLI_INLINE void root_to_world_m3(Implicit_Data *data, int index, float r[3][3], float m[3][3])
 {
-	mul_m3_m3m3(r, data->tfm[index], m);
+  mul_m3_m3m3(r, data->tfm[index], m);
 }
 
 /* ================================ */
 
 bool BPH_mass_spring_solve_velocities(Implicit_Data *data, float dt, ImplicitSolverResult *result)
 {
-#ifdef USE_EIGEN_CORE
-	typedef ConjugateGradient solver_t;
-#endif
-#ifdef USE_EIGEN_CONSTRAINED_CG
-	typedef ConstraintConjGrad solver_t;
-#endif
-
-	data->iM.construct(data->M);
-	data->idFdX.construct(data->dFdX);
-	data->idFdV.construct(data->dFdV);
-	data->iS.construct(data->S);
-
-	solver_t cg;
-	cg.setMaxIterations(100);
-	cg.setTolerance(0.01f);
-
-#ifdef USE_EIGEN_CONSTRAINED_CG
-	cg.filter() = data->S;
-#endif
-
-	data->A = data->M - dt * data->dFdV - dt * dt * data->dFdX;
-	cg.compute(data->A);
-
-	data->B = dt * data->F + dt * dt * data->dFdX * data->V;
-
-#ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
-	printf("==== A ====\n");
-	print_lmatrix(id->A);
-	printf("==== z ====\n");
-	print_lvector(id->z);
-	printf("==== B ====\n");
-	print_lvector(id->B);
-	printf("==== S ====\n");
-	print_lmatrix(id->S);
-#endif
-
-#ifdef USE_EIGEN_CORE
-	data->dV = cg.solve(data->B);
-#endif
-#ifdef USE_EIGEN_CONSTRAINED_CG
-	data->dV = cg.solveWithGuess(data->B, data->z);
-#endif
-
-#ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
-	printf("==== dV ====\n");
-	print_lvector(id->dV);
-	printf("========\n");
-#endif
-
-	data->Vnew = data->V + data->dV;
-
-	switch (cg.info()) {
-		case Eigen::Success:        result->status = BPH_SOLVER_SUCCESS;         break;
-		case Eigen::NoConvergence:  result->status = BPH_SOLVER_NO_CONVERGENCE;  break;
-		case Eigen::InvalidInput:   result->status = BPH_SOLVER_INVALID_INPUT;   break;
-		case Eigen::NumericalIssue: result->status = BPH_SOLVER_NUMERICAL_ISSUE; break;
-	}
-
-	result->iterations = cg.iterations();
-	result->error = cg.error();
-
-	return cg.info() == Eigen::Success;
+#  ifdef USE_EIGEN_CORE
+  typedef ConjugateGradient solver_t;
+#  endif
+#  ifdef USE_EIGEN_CONSTRAINED_CG
+  typedef ConstraintConjGrad solver_t;
+#  endif
+
+  data->iM.construct(data->M);
+  data->idFdX.construct(data->dFdX);
+  data->idFdV.construct(data->dFdV);
+  data->iS.construct(data->S);
+
+  solver_t cg;
+  cg.setMaxIterations(100);
+  cg.setTolerance(0.01f);
+
+#  ifdef USE_EIGEN_CONSTRAINED_CG
+  cg.filter() = data->S;
+#  endif
+
+  data->A = data->M - dt * data->dFdV - dt * dt * data->dFdX;
+  cg.compute(data->A);
+
+  data->B = dt * data->F + dt * dt * data->dFdX * data->V;
+
+#  ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
+  printf("==== A ====\n");
+  print_lmatrix(id->A);
+  printf("==== z ====\n");
+  print_lvector(id->z);
+  printf("==== B ====\n");
+  print_lvector(id->B);
+  printf("==== S ====\n");
+  print_lmatrix(id->S);
+#  endif
+
+#  ifdef USE_EIGEN_CORE
+  data->dV = cg.solve(data->B);
+#  endif
+#  ifdef USE_EIGEN_CONSTRAINED_CG
+  data->dV = cg.solveWithGuess(data->B, data->z);
+#  endif
+
+#  ifdef IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
+  printf("==== dV ====\n");
+  print_lvector(id->dV);
+  printf("========\n");
+#  endif
+
+  data->Vnew = data->V + data->dV;
+
+  switch (cg.info()) {
+    case Eigen::Success:
+      result->status = BPH_SOLVER_SUCCESS;
+      break;
+    case Eigen::NoConvergence:
+      result->status = BPH_SOLVER_NO_CONVERGENCE;
+      break;
+    case Eigen::InvalidInput:
+      result->status = BPH_SOLVER_INVALID_INPUT;
+      break;
+    case Eigen::NumericalIssue:
+      result->status = BPH_SOLVER_NUMERICAL_ISSUE;
+      break;
+  }
+
+  result->iterations = cg.iterations();
+  result->error = cg.error();
+
+  return cg.info() == Eigen::Success;
 }
 
 bool BPH_mass_spring_solve_positions(Implicit_Data *data, float dt)
 {
-	data->Xnew = data->X + data->Vnew * dt;
-	return true;
+  data->Xnew = data->X + data->Vnew * dt;
+  return true;
 }
 
 /* ================================ */
 
 void BPH_mass_spring_apply_result(Implicit_Data *data)
 {
-	data->X = data->Xnew;
-	data->V = data->Vnew;
+  data->X = data->Xnew;
+  data->V = data->Vnew;
 }
 
 void BPH_mass_spring_set_vertex_mass(Implicit_Data *data, int index, float mass)
 {
-	float m[3][3];
-	copy_m3_m3(m, I);
-	mul_m3_fl(m, mass);
-	data->iM.add(index, index, m);
+  float m[3][3];
+  copy_m3_m3(m, I);
+  mul_m3_fl(m, mass);
+  data->iM.add(index, index, m);
 }
 
 void BPH_mass_spring_set_rest_transform(Implicit_Data *data, int index, float tfm[3][3])
 {
-#ifdef CLOTH_ROOT_FRAME
-	copy_m3_m3(data->tfm[index], tfm);
-#else
-	unit_m3(data->tfm[index]);
-	(void)tfm;
-#endif
-}
-
-void BPH_mass_spring_set_motion_state(Implicit_Data *data, int index, const float x[3], const float v[3])
+#  ifdef CLOTH_ROOT_FRAME
+  copy_m3_m3(data->tfm[index], tfm);
+#  else
+  unit_m3(data->tfm[index]);
+  (void)tfm;
+#  endif
+}
+
+void BPH_mass_spring_set_motion_state(Implicit_Data *data,
+                                      int index,
+                                      const float x[3],
+                                      const float v[3])
 {
-	world_to_root_v3(data, index, data->X.v3(index), x);
-	world_to_root_v3(data, index, data->V.v3(index), v);
+  world_to_root_v3(data, index, data->X.v3(index), x);
+  world_to_root_v3(data, index, data->V.v3(index), v);
 }
 
 void BPH_mass_spring_set_position(Implicit_Data *data, int index, const float x[3])
 {
-	world_to_root_v3(data, index, data->X.v3(index), x);
+  world_to_root_v3(data, index, data->X.v3(index), x);
 }
 
 void BPH_mass_spring_set_velocity(Implicit_Data *data, int index, const float v[3])
 {
-	world_to_root_v3(data, index, data->V.v3(index), v);
+  world_to_root_v3(data, index, data->V.v3(index), v);
 }
 
-void BPH_mass_spring_get_motion_state(struct Implicit_Data *data, int index, float x[3], float v[3])
+void BPH_mass_spring_get_motion_state(struct Implicit_Data *data,
+                                      int index,
+                                      float x[3],
+                                      float v[3])
 {
-	if (x) root_to_world_v3(data, index, x, data->X.v3(index));
-	if (v) root_to_world_v3(data, index, v, data->V.v3(index));
+  if (x)
+    root_to_world_v3(data, index, x, data->X.v3(index));
+  if (v)
+    root_to_world_v3(data, index, v, data->V.v3(index));
 }
 
 void BPH_mass_spring_get_position(struct Implicit_Data *data, int index, float x[3])
 {
-	root_to_world_v3(data, index, x, data->X.v3(index));
+  root_to_world_v3(data, index, x, data->X.v3(index));
 }
 
 void BPH_mass_spring_get_new_velocity(Implicit_Data *data, int index, float v[3])
 {
-	root_to_world_v3(data, index, v, data->V.v3(index));
+  root_to_world_v3(data, index, v, data->V.v3(index));
 }
 
 void BPH_mass_spring_set_new_velocity(Implicit_Data *data, int index, const float v[3])
 {
-	world_to_root_v3(data, index, data->V.v3(index), v);
+  world_to_root_v3(data, index, data->V.v3(index), v);
 }
 
 void BPH_mass_spring_clear_constraints(Implicit_Data *data)
 {
-	int numverts = data->numverts;
-	for (int i = 0; i < numverts; ++i) {
-		data->iS.add(i, i, I);
-		zero_v3(data->z.v3(i));
-	}
+  int numverts = data->numverts;
+  for (int i = 0; i < numverts; ++i) {
+    data->iS.add(i, i, I);
+    zero_v3(data->z.v3(i));
+  }
 }
 
 void BPH_mass_spring_add_constraint_ndof0(Implicit_Data *data, int index, const float dV[3])
 {
-	data->iS.sub(index, index, I);
+  data->iS.sub(index, index, I);
 
-	world_to_root_v3(data, index, data->z.v3(index), dV);
+  world_to_root_v3(data, index, data->z.v3(index), dV);
 }
 
-void BPH_mass_spring_add_constraint_ndof1(Implicit_Data *data, int index, const float c1[3], const float c2[3], const float dV[3])
+void BPH_mass_spring_add_constraint_ndof1(
+    Implicit_Data *data, int index, const float c1[3], const float c2[3], const float dV[3])
 {
-	float m[3][3], p[3], q[3], u[3], cmat[3][3];
+  float m[3][3], p[3], q[3], u[3], cmat[3][3];
 
-	world_to_root_v3(data, index, p, c1);
-	outerproduct(cmat, p, p);
-	copy_m3_m3(m, cmat);
+  world_to_root_v3(data, index, p, c1);
+  outerproduct(cmat, p, p);
+  copy_m3_m3(m, cmat);
 
-	world_to_root_v3(data, index, q, c2);
-	outerproduct(cmat, q, q);
-	add_m3_m3m3(m, m, cmat);
+  world_to_root_v3(data, index, q, c2);
+  outerproduct(cmat, q, q);
+  add_m3_m3m3(m, m, cmat);
 
-	/* XXX not sure but multiplication should work here */
-	data->iS.sub(index, index, m);
-//	mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
+  /* XXX not sure but multiplication should work here */
+  data->iS.sub(index, index, m);
+  //  mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
 
-	world_to_root_v3(data, index, u, dV);
-	add_v3_v3(data->z.v3(index), u);
+  world_to_root_v3(data, index, u, dV);
+  add_v3_v3(data->z.v3(index), u);
 }
 
-void BPH_mass_spring_add_constraint_ndof2(Implicit_Data *data, int index, const float c1[3], const float dV[3])
+void BPH_mass_spring_add_constraint_ndof2(Implicit_Data *data,
+                                          int index,
+                                          const float c1[3],
+                                          const float dV[3])
 {
-	float m[3][3], p[3], u[3], cmat[3][3];
+  float m[3][3], p[3], u[3], cmat[3][3];
 
-	world_to_root_v3(data, index, p, c1);
-	outerproduct(cmat, p, p);
-	copy_m3_m3(m, cmat);
+  world_to_root_v3(data, index, p, c1);
+  outerproduct(cmat, p, p);
+  copy_m3_m3(m, cmat);
 
-	data->iS.sub(index, index, m);
-//	mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
+  data->iS.sub(index, index, m);
+  //  mul_m3_m3m3(data->S[index].m, data->S[index].m, m);
 
-	world_to_root_v3(data, index, u, dV);
-	add_v3_v3(data->z.v3(index), u);
+  world_to_root_v3(data, index, u, dV);
+  add_v3_v3(data->z.v3(index), u);
 }
 
 void BPH_mass_spring_clear_forces(Implicit_Data *data)
 {
-	data->F.setZero();
-	data->dFdX.setZero();
-	data->dFdV.setZero();
+  data->F.setZero();
+  data->dFdX.setZero();
+  data->dFdV.setZero();
 }
 
-void BPH_mass_spring_force_reference_frame(Implicit_Data *data, int index, const float acceleration[3], const float omega[3], const float domega_dt[3], float mass)
+void BPH_mass_spring_force_reference_frame(Implicit_Data *data,
+                                           int index,
+                                           const float acceleration[3],
+                                           const float omega[3],
+                                           const float domega_dt[3],
+                                           float mass)
 {
-#ifdef CLOTH_ROOT_FRAME
-	float acc[3], w[3], dwdt[3];
-	float f[3], dfdx[3][3], dfdv[3][3];
-	float euler[3], coriolis[3], centrifugal[3], rotvel[3];
-	float deuler[3][3], dcoriolis[3][3], dcentrifugal[3][3], drotvel[3][3];
-
-	world_to_root_v3(data, index, acc, acceleration);
-	world_to_root_v3(data, index, w, omega);
-	world_to_root_v3(data, index, dwdt, domega_dt);
-
-	cross_v3_v3v3(euler, dwdt, data->X.v3(index));
-	cross_v3_v3v3(coriolis, w, data->V.v3(index));
-	mul_v3_fl(coriolis, 2.0f);
-	cross_v3_v3v3(rotvel, w, data->X.v3(index));
-	cross_v3_v3v3(centrifugal, w, rotvel);
-
-	sub_v3_v3v3(f, acc, euler);
-	sub_v3_v3(f, coriolis);
-	sub_v3_v3(f, centrifugal);
-
-	mul_v3_fl(f, mass); /* F = m * a */
-
-	cross_v3_identity(deuler, dwdt);
-	cross_v3_identity(dcoriolis, w);
-	mul_m3_fl(dcoriolis, 2.0f);
-	cross_v3_identity(drotvel, w);
-	cross_m3_v3m3(dcentrifugal, w, drotvel);
-
-	add_m3_m3m3(dfdx, deuler, dcentrifugal);
-	negate_m3(dfdx);
-	mul_m3_fl(dfdx, mass);
-
-	copy_m3_m3(dfdv, dcoriolis);
-	negate_m3(dfdv);
-	mul_m3_fl(dfdv, mass);
-
-	add_v3_v3(data->F.v3(index), f);
-	data->idFdX.add(index, index, dfdx);
-	data->idFdV.add(index, index, dfdv);
-#else
-	(void)data;
-	(void)index;
-	(void)acceleration;
-	(void)omega;
-	(void)domega_dt;
-#endif
+#  ifdef CLOTH_ROOT_FRAME
+  float acc[3], w[3], dwdt[3];
+  float f[3], dfdx[3][3], dfdv[3][3];
+  float euler[3], coriolis[3], centrifugal[3], rotvel[3];
+  float deuler[3][3], dcoriolis[3][3], dcentrifugal[3][3], drotvel[3][3];
+
+  world_to_root_v3(data, index, acc, acceleration);
+  world_to_root_v3(data, index, w, omega);
+  world_to_root_v3(data, index, dwdt, domega_dt);
+
+  cross_v3_v3v3(euler, dwdt, data->X.v3(index));
+  cross_v3_v3v3(coriolis, w, data->V.v3(index));
+  mul_v3_fl(coriolis, 2.0f);
+  cross_v3_v3v3(rotvel, w, data->X.v3(index));
+  cross_v3_v3v3(centrifugal, w, rotvel);
+
+  sub_v3_v3v3(f, acc, euler);
+  sub_v3_v3(f, coriolis);
+  sub_v3_v3(f, centrifugal);
+
+  mul_v3_fl(f, mass); /* F = m * a */
+
+  cross_v3_identity(deuler, dwdt);
+  cross_v3_identity(dcoriolis, w);
+  mul_m3_fl(dcoriolis, 2.0f);
+  cross_v3_identity(drotvel, w);
+  cross_m3_v3m3(dcentrifugal, w, drotvel);
+
+  add_m3_m3m3(dfdx, deuler, dcentrifugal);
+  negate_m3(dfdx);
+  mul_m3_fl(dfdx, mass);
+
+  copy_m3_m3(dfdv, dcoriolis);
+  negate_m3(dfdv);
+  mul_m3_fl(dfdv, mass);
+
+  add_v3_v3(data->F.v3(index), f);
+  data->idFdX.add(index, index, dfdx);
+  data->idFdV.add(index, index, dfdv);
+#  else
+  (void)data;
+  (void)index;
+  (void)acceleration;
+  (void)omega;
+  (void)domega_dt;
+#  endif
 }
 
 void BPH_mass_spring_force_gravity(Implicit_Data *data, int index, float mass, const float g[3])
 {
-	/* force = mass * acceleration (in this case: gravity) */
-	float f[3];
-	world_to_root_v3(data, index, f, g);
-	mul_v3_fl(f, mass);
+  /* force = mass * acceleration (in this case: gravity) */
+  float f[3];
+  world_to_root_v3(data, index, f, g);
+  mul_v3_fl(f, mass);
 
-	add_v3_v3(data->F.v3(index), f);
+  add_v3_v3(data->F.v3(index), f);
 }
 
 void BPH_mass_spring_force_drag(Implicit_Data *data, float drag)
 {
-	int numverts = data->numverts;
-	for (int i = 0; i < numverts; i++) {
-		float tmp[3][3];
+  int numverts = data->numverts;
+  for (int i = 0; i < numverts; i++) {
+    float tmp[3][3];
 
-		/* NB: uses root space velocity, no need to transform */
-		madd_v3_v3fl(data->F.v3(i), data->V.v3(i), -drag);
+    /* NB: uses root space velocity, no need to transform */
+    madd_v3_v3fl(data->F.v3(i), data->V.v3(i), -drag);
 
-		copy_m3_m3(tmp, I);
-		mul_m3_fl(tmp, -drag);
-		data->idFdV.add(i, i, tmp);
-	}
+    copy_m3_m3(tmp, I);
+    mul_m3_fl(tmp, -drag);
+    data->idFdV.add(i, i, tmp);
+  }
 }
 
-void BPH_mass_spring_force_extern(struct Implicit_Data *data, int i, const float f[3], float dfdx[3][3], float dfdv[3][3])
+void BPH_mass_spring_force_extern(
+    struct Implicit_Data *data, int i, const float f[3], float dfdx[3][3], float dfdv[3][3])
 {
-	float tf[3], tdfdx[3][3], tdfdv[3][3];
-	world_to_root_v3(data, i, tf, f);
-	world_to_root_m3(data, i, tdfdx, dfdx);
-	world_to_root_m3(data, i, tdfdv, dfdv);
+  float tf[3], tdfdx[3][3], tdfdv[3][3];
+  world_to_root_v3(data, i, tf, f);
+  world_to_root_m3(data, i, tdfdx, dfdx);
+  world_to_root_m3(data, i, tdfdv, dfdv);
 
-	add_v3_v3(data->F.v3(i), tf);
-	data->idFdX.add(i, i, tdfdx);
-	data->idFdV.add(i, i, tdfdv);
+  add_v3_v3(data->F.v3(i), tf);
+  data->idFdX.add(i, i, tdfdx);
+  data->idFdV.add(i, i, tdfdv);
 }
 
-static float calc_nor_area_tri(float nor[3], const float v1[3], const float v2[3], const float v3[3])
+static float calc_nor_area_tri(float nor[3],
+                               const float v1[3],
+                               const float v2[3],
+                               const float v3[3])
 {
-	float n1[3], n2[3];
+  float n1[3], n2[3];
 
-	sub_v3_v3v3(n1, v1, v2);
-	sub_v3_v3v3(n2, v2, v3);
+  sub_v3_v3v3(n1, v1, v2);
+  sub_v3_v3v3(n2, v2, v3);
 
-	cross_v3_v3v3(nor, n1, n2);
-	return normalize_v3(nor);
+  cross_v3_v3v3(nor, n1, n2);
+  return normalize_v3(nor);
 }
 
 /* XXX does not support force jacobians yet, since the effector system does not provide them either */
-void BPH_mass_spring_force_face_wind(Implicit_Data *data, int v1, int v2, int v3, const float(*winvec)[3])
+void BPH_mass_spring_force_face_wind(
+    Implicit_Data *data, int v1, int v2, int v3, const float (*winvec)[3])
 {
-	const float effector_scale = 0.02f;
-	float win[3], nor[3], area;
-	float factor;
+  const float effector_scale = 0.02f;
+  float win[3], nor[3], area;
+  float factor;
 
-	// calculate face normal and area
-	area = calc_nor_area_tri(nor, data->X.v3(v1), data->X.v3(v2), data->X.v3(v3));
-	factor = effector_scale * area / 3.0f;
+  // calculate face normal and area
+  area = calc_nor_area_tri(nor, data->X.v3(v1), data->X.v3(v2), data->X.v3(v3));
+  factor = effector_scale * area / 3.0f;
 
-	world_to_root_v3(data, v1, win, winvec[v1]);
-	madd_v3_v3fl(data->F.v3(v1), nor, factor * dot_v3v3(win, nor));
+  world_to_root_v3(data, v1, win, winvec[v1]);
+  madd_v3_v3fl(data->F.v3(v1), nor, factor * dot_v3v3(win, nor));
 
-	world_to_root_v3(data, v2, win, winvec[v2]);
-	madd_v3_v3fl(data->F.v3(v2), nor, factor * dot_v3v3(win, nor));
+  world_to_root_v3(data, v2, win, winvec[v2]);
+  madd_v3_v3fl(data->F.v3(v2), nor, factor * dot_v3v3(win, nor));
 
-	world_to_root_v3(data, v3, win, winvec[v3]);
-	madd_v3_v3fl(data->F.v3(v3), nor, factor * dot_v3v3(win, nor));
+  world_to_root_v3(data, v3, win, winvec[v3]);
+  madd_v3_v3fl(data->F.v3(v3), nor, factor * dot_v3v3(win, nor));
 }
 
-void BPH_mass_spring_force_edge_wind(Implicit_Data *data, int v1, int v2, const float(*winvec)[3])
+void BPH_mass_spring_force_edge_wind(Implicit_Data *data, int v1, int v2, const float (*winvec)[3])
 {
-	const float effector_scale = 0.01;
-	float win[3], dir[3], nor[3], length;
+  const float effector_scale = 0.01;
+  float win[3], dir[3], nor[3], length;
 
-	sub_v3_v3v3(dir, data->X.v3(v1), data->X.v3(v2));
-	length = normalize_v3(dir);
+  sub_v3_v3v3(dir, data->X.v3(v1), data->X.v3(v2));
+  length = normalize_v3(dir);
 
-	world_to_root_v3(data, v1, win, winvec[v1]);
-	madd_v3_v3v3fl(nor, win, dir, -dot_v3v3(win, dir));
-	madd_v3_v3fl(data->F.v3(v1), nor, effector_scale * length);
+  world_to_root_v3(data, v1, win, winvec[v1]);
+  madd_v3_v3v3fl(nor, win, dir, -dot_v3v3(win, dir));
+  madd_v3_v3fl(data->F.v3(v1), nor, effector_scale * length);
 
-	world_to_root_v3(data, v2, win, winvec[v2]);
-	madd_v3_v3v3fl(nor, win, dir, -dot_v3v3(win, dir));
-	madd_v3_v3fl(data->F.v3(v2), nor, effector_scale * length);
+  world_to_root_v3(data, v2, win, winvec[v2]);
+  madd_v3_v3v3fl(nor, win, dir, -dot_v3v3(win, dir));
+  madd_v3_v3fl(data->F.v3(v2), nor, effector_scale * length);
 }
 
 BLI_INLINE void dfdx_spring(float to[3][3], const float dir[3], float length, float L, float k)
 {
-	// dir is unit length direction, rest is spring's restlength, k is spring constant.
-	//return  ( (I-outerprod(dir, dir))*Min(1.0f, rest/length) - I) * -k;
-	outerproduct(to, dir, dir);
-	sub_m3_m3m3(to, I, to);
+  // dir is unit length direction, rest is spring's restlength, k is spring constant.
+  //return  ( (I-outerprod(dir, dir))*Min(1.0f, rest/length) - I) * -k;
+  outerproduct(to, dir, dir);
+  sub_m3_m3m3(to, I, to);
 
-	mul_m3_fl(to, (L / length));
-	sub_m3_m3m3(to, to, I);
-	mul_m3_fl(to, k);
+  mul_m3_fl(to, (L / length));
+  sub_m3_m3m3(to, to, I);
+  mul_m3_fl(to, k);
 }
 
 /* unused */
-#if 0
+#  if 0
 BLI_INLINE void dfdx_damp(float to[3][3], const float dir[3], float length, const float vel[3], float rest, float damping)
 {
-	// inner spring damping   vel is the relative velocity  of the endpoints.
-	//  return (I-outerprod(dir, dir)) * (-damping * -(dot(dir, vel)/Max(length, rest)));
-	mul_fvectorT_fvector(to, dir, dir);
-	sub_fmatrix_fmatrix(to, I, to);
-	mul_fmatrix_S(to,  (-damping * -(dot_v3v3(dir, vel) / MAX2(length, rest))));
+  // inner spring damping   vel is the relative velocity  of the endpoints.
+  //  return (I-outerprod(dir, dir)) * (-damping * -(dot(dir, vel)/Max(length, rest)));
+  mul_fvectorT_fvector(to, dir, dir);
+  sub_fmatrix_fmatrix(to, I, to);
+  mul_fmatrix_S(to,  (-damping * -(dot_v3v3(dir, vel) / MAX2(length, rest))));
 }
-#endif
+#  endif
 
 BLI_INLINE void dfdv_damp(float to[3][3], const float dir[3], float damping)
 {
-	// derivative of force wrt velocity
-	outerproduct(to, dir, dir);
-	mul_m3_fl(to, -damping);
+  // derivative of force wrt velocity
+  outerproduct(to, dir, dir);
+  mul_m3_fl(to, -damping);
 }
 
 BLI_INLINE float fb(float length, float L)
 {
-	float x = length / L;
-	return (-11.541f * powf(x, 4) + 34.193f * powf(x, 3) - 39.083f * powf(x, 2) + 23.116f * x - 9.713f);
+  float x = length / L;
+  return (-11.541f * powf(x, 4) + 34.193f * powf(x, 3) - 39.083f * powf(x, 2) + 23.116f * x -
+          9.713f);
 }
 
 BLI_INLINE float fbderiv(float length, float L)
 {
-	float x = length / L;
+  float x = length / L;
 
-	return (-46.164f * powf(x, 3) + 102.579f * powf(x, 2) - 78.166f * x + 23.116f);
+  return (-46.164f * powf(x, 3) + 102.579f * powf(x, 2) - 78.166f * x + 23.116f);
 }
 
 BLI_INLINE float fbstar(float length, float L, float kb, float cb)
 {
-	float tempfb_fl = kb * fb(length, L);
-	float fbstar_fl = cb * (length - L);
+  float tempfb_fl = kb * fb(length, L);
+  float fbstar_fl = cb * (length - L);
 
-	if (tempfb_fl < fbstar_fl)
-		return fbstar_fl;
-	else
-		return tempfb_fl;
+  if (tempfb_fl < fbstar_fl)
+    return fbstar_fl;
+  else
+    return tempfb_fl;
 }
 
 // function to calculae bending spring force (taken from Choi & Co)
 BLI_INLINE float fbstar_jacobi(float length, float L, float kb, float cb)
 {
-	float tempfb_fl = kb * fb(length, L);
-	float fbstar_fl = cb * (length - L);
+  float tempfb_fl = kb * fb(length, L);
+  float fbstar_fl = cb * (length - L);
 
-	if (tempfb_fl < fbstar_fl) {
-		return -cb;
-	}
-	else {
-		return -kb *fbderiv(length, L);
-	}
+  if (tempfb_fl < fbstar_fl) {
+    return -cb;
+  }
+  else {
+    return -kb * fbderiv(length, L);
+  }
 }
 
 /* calculate elonglation */
-BLI_INLINE bool spring_length(Implicit_Data *data, int i, int j, float r_extent[3], float r_dir[3], float *r_length, float r_vel[3])
+BLI_INLINE bool spring_length(Implicit_Data *data,
+                              int i,
+                              int j,
+                              float r_extent[3],
+                              float r_dir[3],
+                              float *r_length,
+                              float r_vel[3])
 {
-	sub_v3_v3v3(r_extent, data->X.v3(j), data->X.v3(i));
-	sub_v3_v3v3(r_vel, data->V.v3(j), data->V.v3(i));
-	*r_length = len_v3(r_extent);
-
-	if (*r_length > ALMOST_ZERO) {
-#if 0
-		if (length > L) {
-			if ((clmd->sim_parms->flags & CSIMSETT_FLAG_TEARING_ENABLED) &&
-			    ( ((length - L) * 100.0f / L) > clmd->sim_parms->maxspringlen))
-			{
-				// cut spring!
-				s->flags |= CSPRING_FLAG_DEACTIVATE;
-				return false;
-			}
-		}
-#endif
-		mul_v3_v3fl(r_dir, r_extent, 1.0f / (*r_length));
-	}
-	else {
-		zero_v3(r_dir);
-	}
-
-	return true;
-}
-
-BLI_INLINE void apply_spring(Implicit_Data *data, int i, int j, const float f[3], float dfdx[3][3], float dfdv[3][3])
+  sub_v3_v3v3(r_extent, data->X.v3(j), data->X.v3(i));
+  sub_v3_v3v3(r_vel, data->V.v3(j), data->V.v3(i));
+  *r_length = len_v3(r_extent);
+
+  if (*r_length > ALMOST_ZERO) {
+#  if 0
+    if (length > L) {
+      if ((clmd->sim_parms->flags & CSIMSETT_FLAG_TEARING_ENABLED) &&
+          ( ((length - L) * 100.0f / L) > clmd->sim_parms->maxspringlen))
+      {
+        // cut spring!
+        s->flags |= CSPRING_FLAG_DEACTIVATE;
+        return false;
+      }
+    }
+#  endif
+    mul_v3_v3fl(r_dir, r_extent, 1.0f / (*r_length));
+  }
+  else {
+    zero_v3(r_dir);
+  }
+
+  return true;
+}
+
+BLI_INLINE void apply_spring(
+    Implicit_Data *data, int i, int j, const float f[3], float dfdx[3][3], float dfdv[3][3])
 {
-	add_v3_v3(data->F.v3(i), f);
-	sub_v3_v3(data->F.v3(j), f);
-
-	data->idFdX.add(i, i, dfdx);
-	data->idFdX.add(j, j, dfdx);
-	data->idFdX.sub(i, j, dfdx);
-	data->idFdX.sub(j, i, dfdx);
-
-	data->idFdV.add(i, i, dfdv);
-	data->idFdV.add(j, j, dfdv);
-	data->idFdV.sub(i, j, dfdv);
-	data->idFdV.sub(j, i, dfdv);
-}
-
-bool BPH_mass_spring_force_spring_linear(Implicit_Data *data, int i, int j, float restlen,
-                                         float stiffness, float damping, bool no_compress, float clamp_force,
-                                         float r_f[3], float r_dfdx[3][3], float r_dfdv[3][3])
+  add_v3_v3(data->F.v3(i), f);
+  sub_v3_v3(data->F.v3(j), f);
+
+  data->idFdX.add(i, i, dfdx);
+  data->idFdX.add(j, j, dfdx);
+  data->idFdX.sub(i, j, dfdx);
+  data->idFdX.sub(j, i, dfdx);
+
+  data->idFdV.add(i, i, dfdv);
+  data->idFdV.add(j, j, dfdv);
+  data->idFdV.sub(i, j, dfdv);
+  data->idFdV.sub(j, i, dfdv);
+}
+
+bool BPH_mass_spring_force_spring_linear(Implicit_Data *data,
+                                         int i,
+                                         int j,
+                                         float restlen,
+                                         float stiffness,
+                                         float damping,
+                                         bool no_compress,
+                                         float clamp_force,
+                                         float r_f[3],
+                                         float r_dfdx[3][3],
+                                         float r_dfdv[3][3])
 {
-	float extent[3], length, dir[3], vel[3];
+  float extent[3], length, dir[3], vel[3];
 
-	// calculate elonglation
-	spring_length(data, i, j, extent, dir, &length, vel);
+  // calculate elonglation
+  spring_length(data, i, j, extent, dir, &length, vel);
 
-	if (length > restlen || no_compress) {
-		float stretch_force, f[3], dfdx[3][3], dfdv[3][3];
+  if (length > restlen || no_compress) {
+    float stretch_force, f[3], dfdx[3][3], dfdv[3][3];
 
-		stretch_force = stiffness * (length - restlen);
-		if (clamp_force > 0.0f && stretch_force > clamp_force) {
-			stretch_force = clamp_force;
-		}
-		mul_v3_v3fl(f, dir, stretch_force);
+    stretch_force = stiffness * (length - restlen);
+    if (clamp_force > 0.0f && stretch_force > clamp_force) {
+      stretch_force = clamp_force;
+    }
+    mul_v3_v3fl(f, dir, stretch_force);
 
-		// Ascher & Boxman, p.21: Damping only during elonglation
-		// something wrong with it...
-		madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
+    // Ascher & Boxman, p.21: Damping only during elonglation
+    // something wrong with it...
+    madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
 
-		dfdx_spring(dfdx, dir, length, restlen, stiffness);
-		dfdv_damp(dfdv, dir, damping);
+    dfdx_spring(dfdx, dir, length, restlen, stiffness);
+    dfdv_damp(dfdv, dir, damping);
 
-		apply_spring(data, i, j, f, dfdx, dfdv);
+    apply_spring(data, i, j, f, dfdx, dfdv);
 
-		if (r_f) copy_v3_v3(r_f, f);
-		if (r_dfdx) copy_m3_m3(r_dfdx, dfdx);
-		if (r_dfdv) copy_m3_m3(r_dfdv, dfdv);
+    if (r_f)
+      copy_v3_v3(r_f, f);
+    if (r_dfdx)
+      copy_m3_m3(r_dfdx, dfdx);
+    if (r_dfdv)
+      copy_m3_m3(r_dfdv, dfdv);
 
-		return true;
-	}
-	else {
-		if (r_f) zero_v3(r_f);
-		if (r_dfdx) zero_m3(r_dfdx);
-		if (r_dfdv) zero_m3(r_dfdv);
+    return true;
+  }
+  else {
+    if (r_f)
+      zero_v3(r_f);
+    if (r_dfdx)
+      zero_m3(r_dfdx);
+    if (r_dfdv)
+      zero_m3(r_dfdv);
 
-		return false;
-	}
+    return false;
+  }
 }
 
 /* See "Stable but Responsive Cloth" (Choi, Ko 2005) */
-bool BPH_mass_spring_force_spring_bending(Implicit_Data *data, int i, int j, float restlen,
-                                          float kb, float cb,
-                                          float r_f[3], float r_dfdx[3][3], float r_dfdv[3][3])
+bool BPH_mass_spring_force_spring_bending(Implicit_Data *data,
+                                          int i,
+                                          int j,
+                                          float restlen,
+                                          float kb,
+                                          float cb,
+                                          float r_f[3],
+                                          float r_dfdx[3][3],
+                                          float r_dfdv[3][3])
 {
-	float extent[3], length, dir[3], vel[3];
+  float extent[3], length, dir[3], vel[3];
 
-	// calculate elonglation
-	spring_length(data, i, j, extent, dir, &length, vel);
+  // calculate elonglation
+  spring_length(data, i, j, extent, dir, &length, vel);
 
-	if (length < restlen) {
-		float f[3], dfdx[3][3], dfdv[3][3];
+  if (length < restlen) {
+    float f[3], dfdx[3][3], dfdv[3][3];
 
-		mul_v3_v3fl(f, dir, fbstar(length, restlen, kb, cb));
+    mul_v3_v3fl(f, dir, fbstar(length, restlen, kb, cb));
 
-		outerproduct(dfdx, dir, dir);
-		mul_m3_fl(dfdx, fbstar_jacobi(length, restlen, kb, cb));
+    outerproduct(dfdx, dir, dir);
+    mul_m3_fl(dfdx, fbstar_jacobi(length, restlen, kb, cb));
 
-		/* XXX damping not supported */
-		zero_m3(dfdv);
+    /* XXX damping not supported */
+    zero_m3(dfdv);
 
-		apply_spring(data, i, j, f, dfdx, dfdv);
+    apply_spring(data, i, j, f, dfdx, dfdv);
 
-		if (r_f) copy_v3_v3(r_f, f);
-		if (r_dfdx) copy_m3_m3(r_dfdx, dfdx);
-		if (r_dfdv) copy_m3_m3(r_dfdv, dfdv);
+    if (r_f)
+      copy_v3_v3(r_f, f);
+    if (r_dfdx)
+      copy_m3_m3(r_dfdx, dfdx);
+    if (r_dfdv)
+      copy_m3_m3(r_dfdv, dfdv);
 
-		return true;
-	}
-	else {
-		if (r_f) zero_v3(r_f);
-		if (r_dfdx) zero_m3(r_dfdx);
-		if (r_dfdv) zero_m3(r_dfdv);
+    return true;
+  }
+  else {
+    if (r_f)
+      zero_v3(r_f);
+    if (r_dfdx)
+      zero_m3(r_dfdx);
+    if (r_dfdv)
+      zero_m3(r_dfdv);
 
-		return false;
-	}
+    return false;
+  }
 }
 
 /* Jacobian of a direction vector.
@@ -1014,326 +1086,372 @@ bool BPH_mass_spring_force_spring_bending(Implicit_Data *data, int i, int j, flo
  *
  * dD_ij/dx_i = -dD_ij/dx_j = (D_ij * D_ij^T - I) / len_ij
  */
-BLI_INLINE void spring_grad_dir(Implicit_Data *data, int i, int j, float edge[3], float dir[3], float grad_dir[3][3])
+BLI_INLINE void spring_grad_dir(
+    Implicit_Data *data, int i, int j, float edge[3], float dir[3], float grad_dir[3][3])
 {
-	float length;
+  float length;
 
-	sub_v3_v3v3(edge, data->X.v3(j), data->X.v3(i));
-	length = normalize_v3_v3(dir, edge);
+  sub_v3_v3v3(edge, data->X.v3(j), data->X.v3(i));
+  length = normalize_v3_v3(dir, edge);
 
-	if (length > ALMOST_ZERO) {
-		outerproduct(grad_dir, dir, dir);
-		sub_m3_m3m3(grad_dir, I, grad_dir);
-		mul_m3_fl(grad_dir, 1.0f / length);
-	}
-	else {
-		zero_m3(grad_dir);
-	}
+  if (length > ALMOST_ZERO) {
+    outerproduct(grad_dir, dir, dir);
+    sub_m3_m3m3(grad_dir, I, grad_dir);
+    mul_m3_fl(grad_dir, 1.0f / length);
+  }
+  else {
+    zero_m3(grad_dir);
+  }
 }
 
-BLI_INLINE void spring_angbend_forces(Implicit_Data *data, int i, int j, int k,
+BLI_INLINE void spring_angbend_forces(Implicit_Data *data,
+                                      int i,
+                                      int j,
+                                      int k,
                                       const float goal[3],
-                                      float stiffness, float damping,
-                                      int q, const float dx[3], const float dv[3],
+                                      float stiffness,
+                                      float damping,
+                                      int q,
+                                      const float dx[3],
+                                      const float dv[3],
                                       float r_f[3])
 {
-	float edge_ij[3], dir_ij[3];
-	float edge_jk[3], dir_jk[3];
-	float vel_ij[3], vel_jk[3], vel_ortho[3];
-	float f_bend[3], f_damp[3];
-	float fk[3];
-	float dist[3];
+  float edge_ij[3], dir_ij[3];
+  float edge_jk[3], dir_jk[3];
+  float vel_ij[3], vel_jk[3], vel_ortho[3];
+  float f_bend[3], f_damp[3];
+  float fk[3];
+  float dist[3];
 
-	zero_v3(fk);
+  zero_v3(fk);
 
-	sub_v3_v3v3(edge_ij, data->X.v3(j), data->X.v3(i));
-	if (q == i) sub_v3_v3(edge_ij, dx);
-	if (q == j) add_v3_v3(edge_ij, dx);
-	normalize_v3_v3(dir_ij, edge_ij);
+  sub_v3_v3v3(edge_ij, data->X.v3(j), data->X.v3(i));
+  if (q == i)
+    sub_v3_v3(edge_ij, dx);
+  if (q == j)
+    add_v3_v3(edge_ij, dx);
+  normalize_v3_v3(dir_ij, edge_ij);
 
-	sub_v3_v3v3(edge_jk, data->X.v3(k), data->X.v3(j));
-	if (q == j) sub_v3_v3(edge_jk, dx);
-	if (q == k) add_v3_v3(edge_jk, dx);
-	normalize_v3_v3(dir_jk, edge_jk);
+  sub_v3_v3v3(edge_jk, data->X.v3(k), data->X.v3(j));
+  if (q == j)
+    sub_v3_v3(edge_jk, dx);
+  if (q == k)
+    add_v3_v3(edge_jk, dx);
+  normalize_v3_v3(dir_jk, edge_jk);
 
-	sub_v3_v3v3(vel_ij, data->V.v3(j), data->V.v3(i));
-	if (q == i) sub_v3_v3(vel_ij, dv);
-	if (q == j) add_v3_v3(vel_ij, dv);
+  sub_v3_v3v3(vel_ij, data->V.v3(j), data->V.v3(i));
+  if (q == i)
+    sub_v3_v3(vel_ij, dv);
+  if (q == j)
+    add_v3_v3(vel_ij, dv);
 
-	sub_v3_v3v3(vel_jk, data->V.v3(k), data->V.v3(j));
-	if (q == j) sub_v3_v3(vel_jk, dv);
-	if (q == k) add_v3_v3(vel_jk, dv);
+  sub_v3_v3v3(vel_jk, data->V.v3(k), data->V.v3(j));
+  if (q == j)
+    sub_v3_v3(vel_jk, dv);
+  if (q == k)
+    add_v3_v3(vel_jk, dv);
 
-	/* bending force */
-	sub_v3_v3v3(dist, goal, edge_jk);
-	mul_v3_v3fl(f_bend, dist, stiffness);
+  /* bending force */
+  sub_v3_v3v3(dist, goal, edge_jk);
+  mul_v3_v3fl(f_bend, dist, stiffness);
 
-	add_v3_v3(fk, f_bend);
+  add_v3_v3(fk, f_bend);
 
-	/* damping force */
-	madd_v3_v3v3fl(vel_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
-	mul_v3_v3fl(f_damp, vel_ortho, damping);
+  /* damping force */
+  madd_v3_v3v3fl(vel_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
+  mul_v3_v3fl(f_damp, vel_ortho, damping);
 
-	sub_v3_v3(fk, f_damp);
+  sub_v3_v3(fk, f_damp);
 
-	copy_v3_v3(r_f, fk);
+  copy_v3_v3(r_f, fk);
 }
 
 /* Finite Differences method for estimating the jacobian of the force */
-BLI_INLINE void spring_angbend_estimate_dfdx(Implicit_Data *data, int i, int j, int k,
+BLI_INLINE void spring_angbend_estimate_dfdx(Implicit_Data *data,
+                                             int i,
+                                             int j,
+                                             int k,
                                              const float goal[3],
-                                             float stiffness, float damping,
-                                             int q, float dfdx[3][3])
+                                             float stiffness,
+                                             float damping,
+                                             int q,
+                                             float dfdx[3][3])
 {
-	const float delta = 0.00001f; // TODO find a good heuristic for this
-	float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
-	float f[3];
-	int a, b;
+  const float delta = 0.00001f;  // TODO find a good heuristic for this
+  float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
+  float f[3];
+  int a, b;
 
-	zero_m3(dvec_null);
-	unit_m3(dvec_pos);
-	mul_m3_fl(dvec_pos, delta * 0.5f);
-	copy_m3_m3(dvec_neg, dvec_pos);
-	negate_m3(dvec_neg);
+  zero_m3(dvec_null);
+  unit_m3(dvec_pos);
+  mul_m3_fl(dvec_pos, delta * 0.5f);
+  copy_m3_m3(dvec_neg, dvec_pos);
+  negate_m3(dvec_neg);
 
-	/* XXX TODO offset targets to account for position dependency */
+  /* XXX TODO offset targets to account for position dependency */
 
-	for (a = 0; a < 3; ++a) {
-		spring_angbend_forces(data, i, j, k, goal, stiffness, damping,
-		                      q, dvec_pos[a], dvec_null[a], f);
-		copy_v3_v3(dfdx[a], f);
+  for (a = 0; a < 3; ++a) {
+    spring_angbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_pos[a], dvec_null[a], f);
+    copy_v3_v3(dfdx[a], f);
 
-		spring_angbend_forces(data, i, j, k, goal, stiffness, damping,
-		                      q, dvec_neg[a], dvec_null[a], f);
-		sub_v3_v3(dfdx[a], f);
+    spring_angbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_neg[a], dvec_null[a], f);
+    sub_v3_v3(dfdx[a], f);
 
-		for (b = 0; b < 3; ++b) {
-			dfdx[a][b] /= delta;
-		}
-	}
+    for (b = 0; b < 3; ++b) {
+      dfdx[a][b] /= delta;
+    }
+  }
 }
 
 /* Finite Differences method for estimating the jacobian of the force */
-BLI_INLINE void spring_angbend_estimate_dfdv(Implicit_Data *data, int i, int j, int k,
+BLI_INLINE void spring_angbend_estimate_dfdv(Implicit_Data *data,
+                                             int i,
+                                             int j,
+                                             int k,
                                              const float goal[3],
-                                             float stiffness, float damping,
-                                             int q, float dfdv[3][3])
+                                             float stiffness,
+                                             float damping,
+                                             int q,
+                                             float dfdv[3][3])
 {
-	const float delta = 0.00001f; // TODO find a good heuristic for this
-	float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
-	float f[3];
-	int a, b;
+  const float delta = 0.00001f;  // TODO find a good heuristic for this
+  float dvec_null[3][3], dvec_pos[3][3], dvec_neg[3][3];
+  float f[3];
+  int a, b;
 
-	zero_m3(dvec_null);
-	unit_m3(dvec_pos);
-	mul_m3_fl(dvec_pos, delta * 0.5f);
-	copy_m3_m3(dvec_neg, dvec_pos);
-	negate_m3(dvec_neg);
+  zero_m3(dvec_null);
+  unit_m3(dvec_pos);
+  mul_m3_fl(dvec_pos, delta * 0.5f);
+  copy_m3_m3(dvec_neg, dvec_pos);
+  negate_m3(dvec_neg);
 
-	/* XXX TODO offset targets to account for position dependency */
+  /* XXX TODO offset targets to account for position dependency */
 
-	for (a = 0; a < 3; ++a) {
-		spring_angbend_forces(data, i, j, k, goal, stiffness, damping,
-		                      q, dvec_null[a], dvec_pos[a], f);
-		copy_v3_v3(dfdv[a], f);
+  for (a = 0; a < 3; ++a) {
+    spring_angbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_null[a], dvec_pos[a], f);
+    copy_v3_v3(dfdv[a], f);
 
-		spring_angbend_forces(data, i, j, k, goal, stiffness, damping,
-		                      q, dvec_null[a], dvec_neg[a], f);
-		sub_v3_v3(dfdv[a], f);
+    spring_angbend_forces(
+        data, i, j, k, goal, stiffness, damping, q, dvec_null[a], dvec_neg[a], f);
+    sub_v3_v3(dfdv[a], f);
 
-		for (b = 0; b < 3; ++b) {
-			dfdv[a][b] /= delta;
-		}
-	}
+    for (b = 0; b < 3; ++b) {
+      dfdv[a][b] /= delta;
+    }
+  }
 }
 
 /* Angular spring that pulls the vertex toward the local target
  * See "Artistic Simulation of Curly Hair" (Pixar technical memo #12-03a)
  */
-bool BPH_mass_spring_force_spring_bending_angular(Implicit_Data *data, int i, int j, int k,
-                                                  const float target[3], float stiffness, float damping)
+bool BPH_mass_spring_force_spring_bending_angular(Implicit_Data *data,
+                                                  int i,
+                                                  int j,
+                                                  int k,
+                                                  const float target[3],
+                                                  float stiffness,
+                                                  float damping)
 {
-	float goal[3];
-	float fj[3], fk[3];
-	float dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
-	float dfj_dvi[3][3], dfj_dvj[3][3], dfk_dvi[3][3], dfk_dvj[3][3], dfk_dvk[3][3];
-
-	const float vecnull[3] = {0.0f, 0.0f, 0.0f};
-
-	world_to_root_v3(data, j, goal, target);
-
-	spring_angbend_forces(data, i, j, k, goal, stiffness, damping, k, vecnull, vecnull, fk);
-	negate_v3_v3(fj, fk); /* counterforce */
-
-	spring_angbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, i, dfk_dxi);
-	spring_angbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, j, dfk_dxj);
-	spring_angbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, k, dfk_dxk);
-	copy_m3_m3(dfj_dxi, dfk_dxi); negate_m3(dfj_dxi);
-	copy_m3_m3(dfj_dxj, dfk_dxj); negate_m3(dfj_dxj);
-
-	spring_angbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, i, dfk_dvi);
-	spring_angbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, j, dfk_dvj);
-	spring_angbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, k, dfk_dvk);
-	copy_m3_m3(dfj_dvi, dfk_dvi); negate_m3(dfj_dvi);
-	copy_m3_m3(dfj_dvj, dfk_dvj); negate_m3(dfj_dvj);
-
-	/* add forces and jacobians to the solver data */
-
-	add_v3_v3(data->F.v3(j), fj);
-	add_v3_v3(data->F.v3(k), fk);
-
-	data->idFdX.add(j, j, dfj_dxj);
-	data->idFdX.add(k, k, dfk_dxk);
-
-	data->idFdX.add(i, j, dfj_dxi);
-	data->idFdX.add(j, i, dfj_dxi);
-	data->idFdX.add(j, k, dfk_dxj);
-	data->idFdX.add(k, j, dfk_dxj);
-	data->idFdX.add(i, k, dfk_dxi);
-	data->idFdX.add(k, i, dfk_dxi);
-
-	data->idFdV.add(j, j, dfj_dvj);
-	data->idFdV.add(k, k, dfk_dvk);
-
-	data->idFdV.add(i, j, dfj_dvi);
-	data->idFdV.add(j, i, dfj_dvi);
-	data->idFdV.add(j, k, dfk_dvj);
-	data->idFdV.add(k, j, dfk_dvj);
-	data->idFdV.add(i, k, dfk_dvi);
-	data->idFdV.add(k, i, dfk_dvi);
-
-	/* XXX analytical calculation of derivatives below is incorrect.
-	 * This proved to be difficult, but for now just using the finite difference method for
-	 * estimating the jacobians should be sufficient.
-	 */
-#if 0
-	float edge_ij[3], dir_ij[3], grad_dir_ij[3][3];
-	float edge_jk[3], dir_jk[3], grad_dir_jk[3][3];
-	float dist[3], vel_jk[3], vel_jk_ortho[3], projvel[3];
-	float target[3];
-	float tmp[3][3];
-	float fi[3], fj[3], fk[3];
-	float dfi_dxi[3][3], dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
-	float dfdvi[3][3];
-
-	// TESTING
-	damping = 0.0f;
-
-	zero_v3(fi);
-	zero_v3(fj);
-	zero_v3(fk);
-	zero_m3(dfi_dxi);
-	zero_m3(dfj_dxi);
-	zero_m3(dfk_dxi);
-	zero_m3(dfk_dxj);
-	zero_m3(dfk_dxk);
-
-	/* jacobian of direction vectors */
-	spring_grad_dir(data, i, j, edge_ij, dir_ij, grad_dir_ij);
-	spring_grad_dir(data, j, k, edge_jk, dir_jk, grad_dir_jk);
-
-	sub_v3_v3v3(vel_jk, data->V[k], data->V[j]);
-
-	/* bending force */
-	mul_v3_v3fl(target, dir_ij, restlen);
-	sub_v3_v3v3(dist, target, edge_jk);
-	mul_v3_v3fl(fk, dist, stiffness);
-
-	/* damping force */
-	madd_v3_v3v3fl(vel_jk_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
-	madd_v3_v3fl(fk, vel_jk_ortho, damping);
-
-	/* XXX this only holds true as long as we assume straight rest shape!
-	 * eventually will become a bit more involved since the opposite segment
-	 * gets its own target, under condition of having equal torque on both sides.
-	 */
-	copy_v3_v3(fi, fk);
-
-	/* counterforce on the middle point */
-	sub_v3_v3(fj, fi);
-	sub_v3_v3(fj, fk);
-
-	/* === derivatives === */
-
-	madd_m3_m3fl(dfk_dxi, grad_dir_ij, stiffness * restlen);
-
-	madd_m3_m3fl(dfk_dxj, grad_dir_ij, -stiffness * restlen);
-	madd_m3_m3fl(dfk_dxj, I, stiffness);
-
-	madd_m3_m3fl(dfk_dxk, I, -stiffness);
-
-	copy_m3_m3(dfi_dxi, dfk_dxk);
-	negate_m3(dfi_dxi);
-
-	/* dfj_dfi == dfi_dfj due to symmetry,
-	 * dfi_dfj == dfk_dfj due to fi == fk
-	 * XXX see comment above on future bent rest shapes
-	 */
-	copy_m3_m3(dfj_dxi, dfk_dxj);
-
-	/* dfj_dxj == -(dfi_dxj + dfk_dxj) due to fj == -(fi + fk) */
-	sub_m3_m3m3(dfj_dxj, dfj_dxj, dfj_dxi);
-	sub_m3_m3m3(dfj_dxj, dfj_dxj, dfk_dxj);
-
-	/* add forces and jacobians to the solver data */
-	add_v3_v3(data->F[i], fi);
-	add_v3_v3(data->F[j], fj);
-	add_v3_v3(data->F[k], fk);
-
-	add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfi_dxi);
-	add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfj_dxj);
-	add_m3_m3m3(data->dFdX[k].m, data->dFdX[k].m, dfk_dxk);
-
-	add_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfj_dxi);
-	add_m3_m3m3(data->dFdX[block_jk].m, data->dFdX[block_jk].m, dfk_dxj);
-	add_m3_m3m3(data->dFdX[block_ik].m, data->dFdX[block_ik].m, dfk_dxi);
-#endif
-
-	return true;
-}
-
-bool BPH_mass_spring_force_spring_goal(Implicit_Data *data, int i, const float goal_x[3], const float goal_v[3],
-                                       float stiffness, float damping,
-                                       float r_f[3], float r_dfdx[3][3], float r_dfdv[3][3])
+  float goal[3];
+  float fj[3], fk[3];
+  float dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
+  float dfj_dvi[3][3], dfj_dvj[3][3], dfk_dvi[3][3], dfk_dvj[3][3], dfk_dvk[3][3];
+
+  const float vecnull[3] = {0.0f, 0.0f, 0.0f};
+
+  world_to_root_v3(data, j, goal, target);
+
+  spring_angbend_forces(data, i, j, k, goal, stiffness, damping, k, vecnull, vecnull, fk);
+  negate_v3_v3(fj, fk); /* counterforce */
+
+  spring_angbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, i, dfk_dxi);
+  spring_angbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, j, dfk_dxj);
+  spring_angbend_estimate_dfdx(data, i, j, k, goal, stiffness, damping, k, dfk_dxk);
+  copy_m3_m3(dfj_dxi, dfk_dxi);
+  negate_m3(dfj_dxi);
+  copy_m3_m3(dfj_dxj, dfk_dxj);
+  negate_m3(dfj_dxj);
+
+  spring_angbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, i, dfk_dvi);
+  spring_angbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, j, dfk_dvj);
+  spring_angbend_estimate_dfdv(data, i, j, k, goal, stiffness, damping, k, dfk_dvk);
+  copy_m3_m3(dfj_dvi, dfk_dvi);
+  negate_m3(dfj_dvi);
+  copy_m3_m3(dfj_dvj, dfk_dvj);
+  negate_m3(dfj_dvj);
+
+  /* add forces and jacobians to the solver data */
+
+  add_v3_v3(data->F.v3(j), fj);
+  add_v3_v3(data->F.v3(k), fk);
+
+  data->idFdX.add(j, j, dfj_dxj);
+  data->idFdX.add(k, k, dfk_dxk);
+
+  data->idFdX.add(i, j, dfj_dxi);
+  data->idFdX.add(j, i, dfj_dxi);
+  data->idFdX.add(j, k, dfk_dxj);
+  data->idFdX.add(k, j, dfk_dxj);
+  data->idFdX.add(i, k, dfk_dxi);
+  data->idFdX.add(k, i, dfk_dxi);
+
+  data->idFdV.add(j, j, dfj_dvj);
+  data->idFdV.add(k, k, dfk_dvk);
+
+  data->idFdV.add(i, j, dfj_dvi);
+  data->idFdV.add(j, i, dfj_dvi);
+  data->idFdV.add(j, k, dfk_dvj);
+  data->idFdV.add(k, j, dfk_dvj);
+  data->idFdV.add(i, k, dfk_dvi);
+  data->idFdV.add(k, i, dfk_dvi);
+
+  /* XXX analytical calculation of derivatives below is incorrect.
+   * This proved to be difficult, but for now just using the finite difference method for
+   * estimating the jacobians should be sufficient.
+   */
+#  if 0
+  float edge_ij[3], dir_ij[3], grad_dir_ij[3][3];
+  float edge_jk[3], dir_jk[3], grad_dir_jk[3][3];
+  float dist[3], vel_jk[3], vel_jk_ortho[3], projvel[3];
+  float target[3];
+  float tmp[3][3];
+  float fi[3], fj[3], fk[3];
+  float dfi_dxi[3][3], dfj_dxi[3][3], dfj_dxj[3][3], dfk_dxi[3][3], dfk_dxj[3][3], dfk_dxk[3][3];
+  float dfdvi[3][3];
+
+  // TESTING
+  damping = 0.0f;
+
+  zero_v3(fi);
+  zero_v3(fj);
+  zero_v3(fk);
+  zero_m3(dfi_dxi);
+  zero_m3(dfj_dxi);
+  zero_m3(dfk_dxi);
+  zero_m3(dfk_dxj);
+  zero_m3(dfk_dxk);
+
+  /* jacobian of direction vectors */
+  spring_grad_dir(data, i, j, edge_ij, dir_ij, grad_dir_ij);
+  spring_grad_dir(data, j, k, edge_jk, dir_jk, grad_dir_jk);
+
+  sub_v3_v3v3(vel_jk, data->V[k], data->V[j]);
+
+  /* bending force */
+  mul_v3_v3fl(target, dir_ij, restlen);
+  sub_v3_v3v3(dist, target, edge_jk);
+  mul_v3_v3fl(fk, dist, stiffness);
+
+  /* damping force */
+  madd_v3_v3v3fl(vel_jk_ortho, vel_jk, dir_jk, -dot_v3v3(vel_jk, dir_jk));
+  madd_v3_v3fl(fk, vel_jk_ortho, damping);
+
+  /* XXX this only holds true as long as we assume straight rest shape!
+   * eventually will become a bit more involved since the opposite segment
+   * gets its own target, under condition of having equal torque on both sides.
+   */
+  copy_v3_v3(fi, fk);
+
+  /* counterforce on the middle point */
+  sub_v3_v3(fj, fi);
+  sub_v3_v3(fj, fk);
+
+  /* === derivatives === */
+
+  madd_m3_m3fl(dfk_dxi, grad_dir_ij, stiffness * restlen);
+
+  madd_m3_m3fl(dfk_dxj, grad_dir_ij, -stiffness * restlen);
+  madd_m3_m3fl(dfk_dxj, I, stiffness);
+
+  madd_m3_m3fl(dfk_dxk, I, -stiffness);
+
+  copy_m3_m3(dfi_dxi, dfk_dxk);
+  negate_m3(dfi_dxi);
+
+  /* dfj_dfi == dfi_dfj due to symmetry,
+   * dfi_dfj == dfk_dfj due to fi == fk
+   * XXX see comment above on future bent rest shapes
+   */
+  copy_m3_m3(dfj_dxi, dfk_dxj);
+
+  /* dfj_dxj == -(dfi_dxj + dfk_dxj) due to fj == -(fi + fk) */
+  sub_m3_m3m3(dfj_dxj, dfj_dxj, dfj_dxi);
+  sub_m3_m3m3(dfj_dxj, dfj_dxj, dfk_dxj);
+
+  /* add forces and jacobians to the solver data */
+  add_v3_v3(data->F[i], fi);
+  add_v3_v3(data->F[j], fj);
+  add_v3_v3(data->F[k], fk);
+
+  add_m3_m3m3(data->dFdX[i].m, data->dFdX[i].m, dfi_dxi);
+  add_m3_m3m3(data->dFdX[j].m, data->dFdX[j].m, dfj_dxj);
+  add_m3_m3m3(data->dFdX[k].m, data->dFdX[k].m, dfk_dxk);
+
+  add_m3_m3m3(data->dFdX[block_ij].m, data->dFdX[block_ij].m, dfj_dxi);
+  add_m3_m3m3(data->dFdX[block_jk].m, data->dFdX[block_jk].m, dfk_dxj);
+  add_m3_m3m3(data->dFdX[block_ik].m, data->dFdX[block_ik].m, dfk_dxi);
+#  endif
+
+  return true;
+}
+
+bool BPH_mass_spring_force_spring_goal(Implicit_Data *data,
+                                       int i,
+                                       const float goal_x[3],
+                                       const float goal_v[3],
+                                       float stiffness,
+                                       float damping,
+                                       float r_f[3],
+                                       float r_dfdx[3][3],
+                                       float r_dfdv[3][3])
 {
-	float root_goal_x[3], root_goal_v[3], extent[3], length, dir[3], vel[3];
-	float f[3], dfdx[3][3], dfdv[3][3];
-
-	/* goal is in world space */
-	world_to_root_v3(data, i, root_goal_x, goal_x);
-	world_to_root_v3(data, i, root_goal_v, goal_v);
-
-	sub_v3_v3v3(extent, root_goal_x, data->X.v3(i));
-	sub_v3_v3v3(vel, root_goal_v, data->V.v3(i));
-	length = normalize_v3_v3(dir, extent);
-
-	if (length > ALMOST_ZERO) {
-		mul_v3_v3fl(f, dir, stiffness * length);
-
-		// Ascher & Boxman, p.21: Damping only during elonglation
-		// something wrong with it...
-		madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
-
-		dfdx_spring(dfdx, dir, length, 0.0f, stiffness);
-		dfdv_damp(dfdv, dir, damping);
-
-		add_v3_v3(data->F.v3(i), f);
-		data->idFdX.add(i, i, dfdx);
-		data->idFdV.add(i, i, dfdv);
-
-		if (r_f) copy_v3_v3(r_f, f);
-		if (r_dfdx) copy_m3_m3(r_dfdx, dfdx);
-		if (r_dfdv) copy_m3_m3(r_dfdv, dfdv);
-
-		return true;
-	}
-	else {
-		if (r_f) zero_v3(r_f);
-		if (r_dfdx) zero_m3(r_dfdx);
-		if (r_dfdv) zero_m3(r_dfdv);
-
-		return false;
-	}
+  float root_goal_x[3], root_goal_v[3], extent[3], length, dir[3], vel[3];
+  float f[3], dfdx[3][3], dfdv[3][3];
+
+  /* goal is in world space */
+  world_to_root_v3(data, i, root_goal_x, goal_x);
+  world_to_root_v3(data, i, root_goal_v, goal_v);
+
+  sub_v3_v3v3(extent, root_goal_x, data->X.v3(i));
+  sub_v3_v3v3(vel, root_goal_v, data->V.v3(i));
+  length = normalize_v3_v3(dir, extent);
+
+  if (length > ALMOST_ZERO) {
+    mul_v3_v3fl(f, dir, stiffness * length);
+
+    // Ascher & Boxman, p.21: Damping only during elonglation
+    // something wrong with it...
+    madd_v3_v3fl(f, dir, damping * dot_v3v3(vel, dir));
+
+    dfdx_spring(dfdx, dir, length, 0.0f, stiffness);
+    dfdv_damp(dfdv, dir, damping);
+
+    add_v3_v3(data->F.v3(i), f);
+    data->idFdX.add(i, i, dfdx);
+    data->idFdV.add(i, i, dfdv);
+
+    if (r_f)
+      copy_v3_v3(r_f, f);
+    if (r_dfdx)
+      copy_m3_m3(r_dfdx, dfdx);
+    if (r_dfdv)
+      copy_m3_m3(r_dfdv, dfdv);
+
+    return true;
+  }
+  else {
+    if (r_f)
+      zero_v3(r_f);
+    if (r_dfdx)
+      zero_m3(r_dfdx);
+    if (r_dfdv)
+      zero_m3(r_dfdv);
+
+    return false;
+  }
 }
 
 #endif /* IMPLICIT_SOLVER_EIGEN */