Moved collision response into the main cloth sim source file and fixed

some coordinate transform issues.

Collision response should be regarded as part of the dynamics system
instead of the basic collision detection.

1 files changed, 4 insertions, 64 deletions

diff --git a/source/blender/blenkernel/intern/collision.c b/source/blender/blenkernel/intern/collision.c
index b13eb9d4574..a8273b502a1 100644
--- a/source/blender/blenkernel/intern/collision.c
+++ b/source/blender/blenkernel/intern/collision.c
@@ -958,80 +958,20 @@ BLI_INLINE void max_v3_v3v3(float r[3], const float a[3], const float b[3])
 	r[2] = max_ff(a[2], b[2]);
 }
 
-bool cloth_points_collpair_response(ClothModifierData *clmd, CollisionModifierData *collmd, PartDeflect *pd, CollPair *collpair, float dt, float r_impulse[3])
+void collision_get_collider_velocity(float vel_old[3], float vel_new[3], CollisionModifierData *collmd, CollPair *collpair)
 {
-	bool result = false;
-	float restitution = (1.0f - clmd->coll_parms->damping) * (1.0f - pd->pdef_sbdamp);
-	Cloth *cloth1 = clmd->clothObject;
-	
 	float u1, u2, u3;
-	float v1[3], v2_old[3], v2_new[3], v_rel_old[3], v_rel_new[3];
-	float epsilon2 = BLI_bvhtree_getepsilon ( collmd->bvhtree );
-
-	float margin_distance = 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;
 	
 	/* compute barycentric coordinates */
 	collision_compute_barycentric(collpair->pb,
 	                              collmd->current_x[collpair->bp1].co,
 	                              collmd->current_x[collpair->bp2].co,
 	                              collmd->current_x[collpair->bp3].co,
-	                              &u1, &u2, &u3 );
-	
-	/* Calculate relative velocity */
-	copy_v3_v3(v1, cloth1->verts[collpair->ap1].tv);
+	                              &u1, &u2, &u3);
 	
-	collision_interpolateOnTriangle(v2_new, collmd->current_v[collpair->bp1].co, collmd->current_v[collpair->bp2].co, collmd->current_v[collpair->bp3].co, u1, u2, u3);
+	collision_interpolateOnTriangle(vel_new, collmd->current_v[collpair->bp1].co, collmd->current_v[collpair->bp2].co, collmd->current_v[collpair->bp3].co, u1, u2, u3);
 	/* XXX assume constant velocity of the collider for now */
-	copy_v3_v3(v2_old, v2_new);
-	
-	/* 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);
-		
-		repulse = -margin_distance / dt + dot_v3v3(v1, collpair->normal);
-		
-		if (margin_distance < -epsilon2) {
-			bounce = -(v_nor_new + v_nor_old * restitution);
-			mul_v3_v3fl(r_impulse, collpair->normal, max_ff(repulse, bounce));
-		}
-		else {
-			bounce = 0.0f;
-			mul_v3_v3fl(r_impulse, collpair->normal, repulse);
-		}
-		
-		result = true;
-	}
-	
-	return result;
+	copy_v3_v3(vel_old, vel_new);
 }
 
 static bool cloth_points_collision_response_static(ClothModifierData *clmd, CollisionModifierData *collmd, PartDeflect *pd,