1 files changed, 344 insertions, 47 deletions

diff --git a/source/blender/blenkernel/intern/particle_system.c b/source/blender/blenkernel/intern/particle_system.c
index 89db2dd45a9..cf4bf32fd77 100644
--- a/source/blender/blenkernel/intern/particle_system.c
+++ b/source/blender/blenkernel/intern/particle_system.c
@@ -84,6 +84,7 @@
 #include "BKE_object.h"
 #include "BKE_material.h"
 #include "BKE_cloth.h"
+#include "BKE_key.h"
 #include "BKE_lattice.h"
 #include "BKE_pointcache.h"
 #include "BKE_mesh.h"
@@ -1201,7 +1202,7 @@ void psys_make_temp_pointcache(Object *ob, ParticleSystem *psys)
 		PTCacheID pid;
 		BKE_ptcache_id_from_particles(&pid, ob, psys);
 		cache->flag &= ~PTCACHE_DISK_CACHE;
-		BKE_ptcache_disk_to_mem(&pid);
+		BKE_ptcache_disk_to_mem(&pid, false);
 		cache->flag |= PTCACHE_DISK_CACHE;
 	}
 }
@@ -1291,7 +1292,7 @@ static void psys_update_effectors(ParticleSimulationData *sim)
 {
 	pdEndEffectors(&sim->psys->effectors);
 	sim->psys->effectors = pdInitEffectors(sim->scene, sim->ob, sim->psys,
-	                                       sim->psys->part->effector_weights, true);
+	                                       sim->psys->part->effector_weights);
 	precalc_guides(sim, sim->psys->effectors);
 }
 
@@ -2896,79 +2897,93 @@ static void collision_check(ParticleSimulationData *sim, int p, float dfra, floa
 /************************************************/
 /*			Hair								*/
 /************************************************/
-/* check if path cache or children need updating and do it if needed */
-static void psys_update_path_cache(ParticleSimulationData *sim, float cfra)
+
+static bool psys_needs_path_cache(ParticleSimulationData *sim)
 {
 	ParticleSystem *psys = sim->psys;
 	ParticleSettings *part = psys->part;
 	ParticleEditSettings *pset = &sim->scene->toolsettings->particle;
 	Base *base;
-	int distr=0, alloc=0, skip=0;
-
-	if ((psys->part->childtype && psys->totchild != psys_get_tot_child(sim->scene, psys)) || psys->recalc&PSYS_RECALC_RESET)
-		alloc=1;
-
-	if (alloc || psys->recalc&PSYS_RECALC_CHILD || (psys->vgroup[PSYS_VG_DENSITY] && (sim->ob && sim->ob->mode & OB_MODE_WEIGHT_PAINT)))
-		distr=1;
-
-	if (distr) {
-		if (alloc)
-			realloc_particles(sim, sim->psys->totpart);
-
-		if (psys_get_tot_child(sim->scene, psys)) {
-			/* don't generate children while computing the hair keys */
-			if (!(psys->part->type == PART_HAIR) || (psys->flag & PSYS_HAIR_DONE)) {
-				distribute_particles(sim, PART_FROM_CHILD);
-
-				if (part->childtype==PART_CHILD_FACES && part->parents != 0.0f)
-					psys_find_parents(sim);
+	
+	/* particle instance modifier with "path" option need cached paths even if particle system doesn't */
+	for (base = sim->scene->base.first; base; base= base->next) {
+		ModifierData *md = modifiers_findByType(base->object, eModifierType_ParticleInstance);
+		if (md) {
+			ParticleInstanceModifierData *pimd = (ParticleInstanceModifierData *)md;
+			if (pimd->flag & eParticleInstanceFlag_Path && pimd->ob == sim->ob && pimd->psys == (psys - (ParticleSystem*)sim->ob->particlesystem.first)) {
+				return true;
 			}
 		}
-		else
-			psys_free_children(psys);
 	}
-
+	
 	if ((part->type==PART_HAIR || psys->flag&PSYS_KEYED || psys->pointcache->flag & PTCACHE_BAKED)==0)
-		skip = 1; /* only hair, keyed and baked stuff can have paths */
+		return false; /* only hair, keyed and baked stuff can have paths */
 	else if (part->ren_as != PART_DRAW_PATH && !(part->type==PART_HAIR && ELEM(part->ren_as, PART_DRAW_OB, PART_DRAW_GR)))
-		skip = 1; /* particle visualization must be set as path */
+		return false; /* particle visualization must be set as path */
 	else if (!psys->renderdata) {
-		if (part->draw_as != PART_DRAW_REND)
-			skip = 1; /* draw visualization */
+		if (!ELEM(part->draw_as, PART_DRAW_REND, PART_DRAW_HULL))
+			return false; /* not a mode that requires paths */
 		else if (psys->pointcache->flag & PTCACHE_BAKING)
-			skip = 1; /* no need to cache paths while baking dynamics */
+			return false; /* no need to cache paths while baking dynamics */
 		else if (psys_in_edit_mode(sim->scene, psys)) {
 			if ((pset->flag & PE_DRAW_PART)==0)
-				skip = 1;
+				return false;
 			else if (part->childtype==0 && (psys->flag & PSYS_HAIR_DYNAMICS && psys->pointcache->flag & PTCACHE_BAKED)==0)
-				skip = 1; /* in edit mode paths are needed for child particles and dynamic hair */
+				return false; /* in edit mode paths are needed for child particles and dynamic hair */
 		}
 	}
+	
+	return true;
+}
 
+/* check if path cache or children need updating and do it if needed */
+static void psys_update_path_cache(ParticleSimulationData *sim, float cfra)
+{
+	ParticleSystem *psys = sim->psys;
+	ParticleSettings *part = psys->part;
 
-	/* particle instance modifier with "path" option need cached paths even if particle system doesn't */
-	for (base = sim->scene->base.first; base; base= base->next) {
-		ModifierData *md = modifiers_findByType(base->object, eModifierType_ParticleInstance);
-		if (md) {
-			ParticleInstanceModifierData *pimd = (ParticleInstanceModifierData *)md;
-			if (pimd->flag & eParticleInstanceFlag_Path && pimd->ob == sim->ob && pimd->psys == (psys - (ParticleSystem*)sim->ob->particlesystem.first)) {
-				skip = 0;
-				break;
+	/* check if particles need to be reallocated or redistributed */
+	{
+		bool alloc = false, distr = false;
+		
+		if ((psys->part->childtype && psys->totchild != psys_get_tot_child(sim->scene, psys)) || psys->recalc&PSYS_RECALC_RESET)
+			alloc = true;
+		
+		if (alloc || psys->recalc&PSYS_RECALC_CHILD || (psys->vgroup[PSYS_VG_DENSITY] && (sim->ob && sim->ob->mode & OB_MODE_WEIGHT_PAINT)))
+			distr = true;
+		
+		if (distr) {
+			if (alloc)
+				realloc_particles(sim, sim->psys->totpart);
+			
+			if (psys_get_tot_child(sim->scene, psys)) {
+				/* don't generate children while computing the hair keys */
+				if (!(psys->part->type == PART_HAIR) || (psys->flag & PSYS_HAIR_DONE)) {
+					distribute_particles(sim, PART_FROM_CHILD);
+					
+					if (part->childtype==PART_CHILD_FACES && part->parents != 0.0f)
+						psys_find_parents(sim);
+				}
 			}
+			else
+				psys_free_children(psys);
 		}
 	}
 
-	if (!skip) {
+	if (psys_needs_path_cache(sim)) {
+		
 		psys_cache_paths(sim, cfra);
 
 		/* for render, child particle paths are computed on the fly */
 		if (part->childtype) {
+			bool do_child_paths = true;
+			
 			if (!psys->totchild)
-				skip = 1;
+				do_child_paths = false;
 			else if (psys->part->type == PART_HAIR && (psys->flag & PSYS_HAIR_DONE)==0)
-				skip = 1;
+				do_child_paths = false;
 
-			if (!skip)
+			if (do_child_paths)
 				psys_cache_child_paths(sim, cfra, 0);
 		}
 	}
@@ -3015,6 +3030,120 @@ static MDeformVert *hair_set_pinning(MDeformVert *dvert, float weight)
 	return dvert;
 }
 
+bool psys_hair_update_preview(ParticleSimulationData *sim)
+{
+#ifdef USE_PARTICLE_PREVIEW
+	ParticleSystem *psys = sim->psys;
+	ParticleSettings *part = psys->part;
+	DerivedMesh *dm = sim->psmd->dm;
+	const float ratio = psys->hair_preview_factor * 0.01f;
+	/* target number of simulated hairs
+	 * NOTE: this has to be reached exactly, in order to allow
+	 * comparison with the psys->hair_num_simulated value!
+	 */
+	const int num_simulated = psys->totpart * ratio;
+	
+	if (!(part->type == PART_HAIR))
+		return false;
+	if (num_simulated == psys->hair_num_simulated)
+		return false;
+	
+	{ /* Random hair selection method */
+		KDTree *tree = BLI_kdtree_new(num_simulated); /* kdtree for finding nearest simulated hairs for blending */
+		RNG *rng = BLI_rng_new(98250 + psys->seed);
+		ParticleData *pa;
+		int cur_simulated = 0;
+		int i;
+		
+		/* construct a kd-tree of all simulated hairs */
+		pa = psys->particles;
+		for (i = 0; i < psys->totpart; ++i, ++pa) {
+			bool simulate = true;
+			if (cur_simulated == num_simulated) {
+				/* don't simulate more than the total number */
+				simulate = false;
+			}
+			else if (num_simulated - cur_simulated <= psys->totpart - i) {
+				/* only allow disabling if the target sim number
+				 * can be reached with the remaining hairs
+				 */
+				simulate = BLI_rng_get_float(rng) < ratio;
+			}
+			
+			if (simulate) {
+				float co[3];
+				
+				pa->flag &= ~PARS_HAIR_BLEND;
+				
+				if (pa->totkey >= 2) {
+					psys_particle_on_dm(dm, part->from, pa->num, pa->num_dmcache, pa->fuv, pa->foffset, co, 0, 0, 0, 0, 0);
+					BLI_kdtree_insert(tree, i, co);
+				}
+				
+				++cur_simulated;
+			}
+			else {
+				pa->flag |= PARS_HAIR_BLEND;
+			}
+		}
+		
+		BLI_kdtree_balance(tree);
+		
+		/* look up nearest simulated hairs for preview hairs and calculate blending weights */
+		pa = psys->particles;
+		for (i = 0; i < psys->totpart; ++i, ++pa) {
+			if (pa->flag & PARS_HAIR_BLEND) {
+				float co[3];
+				int maxw, w;
+				KDTreeNearest nearest[4];
+				
+				psys_particle_on_dm(dm, part->from, pa->num, pa->num_dmcache, pa->fuv, pa->foffset, co, 0, 0, 0, 0, 0);
+				maxw = BLI_kdtree_find_nearest_n(tree, co, nearest, 4);
+				if (maxw == 1) {
+					pa->blend_index[0] = nearest[0].index;
+					pa->blend_weight[0] = 1.0f;
+				}
+				else if (maxw > 1) {
+					float norm, totdist = 0.0f;
+					for (w = 0; w < maxw; ++w)
+						totdist += nearest[w].dist;
+					norm = totdist > 0.0f ? 1.0f / (totdist * (float)(maxw - 1)) : 0.0f;
+					
+					for (w = 0; w < maxw; ++w) {
+						pa->blend_index[w] = nearest[w].index;
+						pa->blend_weight[w] = (totdist - nearest[w].dist) * norm;
+					}
+				}
+				/* clear unused weights */
+				for (w = maxw; w < 4; ++w) {
+					pa->blend_index[w] = -1;
+					pa->blend_weight[w] = 0.0f;
+				}
+			}
+			else {
+				pa->blend_index[0] = -1;
+				pa->blend_index[1] = -1;
+				pa->blend_index[2] = -1;
+				pa->blend_index[3] = -1;
+				pa->blend_weight[0] = 0.0f;
+				pa->blend_weight[1] = 0.0f;
+				pa->blend_weight[2] = 0.0f;
+				pa->blend_weight[3] = 0.0f;
+			}
+		}
+		
+		BLI_kdtree_free(tree);
+		BLI_rng_free(rng);
+	}
+	
+	psys->hair_num_simulated = num_simulated;
+	return true;
+#else
+	(void)sim;
+	return false;
+#endif
+}
+
 static void hair_create_input_dm(ParticleSimulationData *sim, int totpoint, int totedge, DerivedMesh **r_dm, ClothHairData **r_hairdata)
 {
 	ParticleSystem *psys = sim->psys;
@@ -3030,6 +3159,8 @@ static void hair_create_input_dm(ParticleSimulationData *sim, int totpoint, int
 	float hairmat[4][4];
 	float max_length;
 	float hair_radius;
+	float *shapekey_data, *shapekey;
+	int totshapekey;
 	
 	dm = *r_dm;
 	if (!dm) {
@@ -3060,6 +3191,8 @@ static void hair_create_input_dm(ParticleSimulationData *sim, int totpoint, int
 	/* XXX placeholder for more flexible future hair settings */
 	hair_radius = part->size;
 	
+	shapekey = shapekey_data = BKE_key_evaluate_particles(sim->ob, psys, sim->scene ? sim->scene->r.cfra : 0.0f, &totshapekey);
+	
 	/* make vgroup for pin roots etc.. */
 	hair_index = 1;
 	LOOP_PARTICLES {
@@ -3080,8 +3213,15 @@ static void hair_create_input_dm(ParticleSimulationData *sim, int totpoint, int
 			ClothHairData *hair;
 			float *co, *co_next;
 			
-			co = key->co;
-			co_next = (key+1)->co;
+			if (shapekey) {
+				co = shapekey;
+				co_next = shapekey + 3;
+				shapekey += 3;
+			}
+			else {
+				co = key->co;
+				co_next = (key+1)->co;
+			}
 			
 			/* create fake root before actual root to resist bending */
 			if (k==0) {
@@ -3101,6 +3241,14 @@ static void hair_create_input_dm(ParticleSimulationData *sim, int totpoint, int
 				
 				dvert = hair_set_pinning(dvert, 1.0f);
 				
+#ifdef USE_PARTICLE_PREVIEW
+				/* tag vert if hair is not simulated */
+				if (pa->flag & PARS_HAIR_BLEND)
+					mvert->flag |= ME_VERT_TMP_TAG;
+				else
+					mvert->flag &= ~ME_VERT_TMP_TAG;
+#endif
+				
 				mvert++;
 				medge++;
 			}
@@ -3127,6 +3275,14 @@ static void hair_create_input_dm(ParticleSimulationData *sim, int totpoint, int
 			else
 				dvert = hair_set_pinning(dvert, 1.0f);
 			
+#ifdef USE_PARTICLE_PREVIEW
+			/* tag vert if hair is not simulated */
+			if (pa->flag & PARS_HAIR_BLEND)
+				mvert->flag |= ME_VERT_TMP_TAG;
+			else
+				mvert->flag &= ~ME_VERT_TMP_TAG;
+#endif
+			
 			mvert++;
 			if (k)
 				medge++;
@@ -3136,6 +3292,105 @@ static void hair_create_input_dm(ParticleSimulationData *sim, int totpoint, int
 	}
 }
 
+#ifdef USE_PARTICLE_PREVIEW
+static void hair_deform_preview_curve(ParticleSystem *psys, ParticleData *pa, float (*deformedVerts)[3], ClothHairData *hairdata)
+{
+	ParticleData *particles = psys->particles;
+	HairKey *hkey;
+	float (*vert)[3];
+	ClothHairData *root;
+	int k;
+	float totlen, norm;
+	
+	/* first key is root, no blending for them */
+	if (pa->totkey < 2)
+		return;
+	
+	/* calculate normalization factor to equally parameterize hairs */
+	totlen = 0.0f;
+	hkey = pa->hair;
+	for (k = 0; k < pa->totkey - 1; ++k, ++hkey)
+		totlen += len_v3v3((hkey+1)->co, hkey->co);
+	norm = totlen > 0.0f ? 1.0f / totlen : 0.0f;
+	
+	totlen = 0.0f;
+	hkey = pa->hair;
+	vert = deformedVerts + pa->hair_index;
+	root = hairdata + pa->hair_index;
+	for (k = 0; k < pa->totkey; ++k, ++hkey, ++vert, ++root) {
+		float param;
+		int w;
+		
+		if (k == 0) /* skip root vertex */
+			continue;
+		param = totlen * norm;
+		totlen += len_v3v3(hkey->co, (hkey-1)->co);
+		
+		zero_v3(vert[0]);
+		for (w = 0; w < 4; ++w) {
+			ParticleData *blend_pa;
+			float (*blend_vert)[3];
+			ClothHairData *blend_hair;
+			float blend_key, blend_factor;
+			int blend_totkey, blend_index;
+			float co[3];
+			
+			if (pa->blend_index[w] < 0)
+				continue;
+			
+			blend_pa = particles + pa->blend_index[w];
+			blend_totkey = blend_pa->totkey;
+			
+			blend_key = param * (float)blend_totkey;
+			blend_index = (int)blend_key;
+			if (blend_index >= blend_totkey - 1) {
+				blend_index = blend_totkey - 2;
+				blend_factor = 1.0f;
+			}
+			else {
+				blend_factor = blend_key - floorf(blend_key);
+			}
+			
+			/* pa->hair_index is set when creating input_dm,
+			 * use it here to map to output mvert index
+			 */
+			blend_vert = deformedVerts + blend_pa->hair_index + blend_index;
+			blend_hair = hairdata + blend_pa->hair_index + blend_index;
+			
+			interp_v3_v3v3(co, blend_vert[0], blend_vert[1], blend_factor);
+			
+			/* transform parent vector from world to root space, then back into root space of the blended hair */
+			sub_v3_v3(co, blend_hair->loc);
+			/* note: rotation transform disabled, this does not work nicely with global force directions (gravity, wind etc.)
+			 * these forces would also get rotated, giving movement in a different direction than the force would actually incur.
+			 * would have to split internal (stretch, bend) and external forces somehow to make this plausible
+			 */
+#if 0
+			mul_transposed_m3_v3(blend_hair->rot, co);
+			mul_m3_v3(root->rot, co);
+#endif
+			add_v3_v3(co, root->loc);
+			
+			madd_v3_v3fl(vert[0], co, pa->blend_weight[w]);
+		}
+	}
+}
+
+static void hair_deform_preview_hairs(ParticleSimulationData *sim, float (*deformedVerts)[3], ClothHairData *roots)
+{
+	ParticleSystem *psys = sim->psys;
+	ParticleData *pa;
+	int p;
+
+	pa = psys->particles;
+	for (p = 0; p < psys->totpart; ++p, ++pa) {
+		if (pa->flag & PARS_HAIR_BLEND) {
+			hair_deform_preview_curve(psys, pa, deformedVerts, roots);
+		}
+	}
+}
+#endif
+
 static void do_hair_dynamics(ParticleSimulationData *sim)
 {
 	ParticleSystem *psys = sim->psys;
@@ -3146,6 +3401,11 @@ static void do_hair_dynamics(ParticleSimulationData *sim)
 	float (*deformedVerts)[3];
 	bool realloc_roots;
 	
+	if (psys_hair_update_preview(sim)) {
+		if (psys->clmd)
+			cloth_free_modifier(psys->clmd);
+	}
+	
 	if (!psys->clmd) {
 		psys->clmd = (ClothModifierData*)modifier_new(eModifierType_Cloth);
 		psys->clmd->sim_parms->goalspring = 0.0f;
@@ -3197,6 +3457,9 @@ static void do_hair_dynamics(ParticleSimulationData *sim)
 	psys->hair_out_dm->getVertCos(psys->hair_out_dm, deformedVerts);
 	
 	clothModifier_do(psys->clmd, sim->scene, sim->ob, psys->hair_in_dm, deformedVerts);
+#ifdef USE_PARTICLE_PREVIEW
+	hair_deform_preview_hairs(sim, deformedVerts, psys->clmd->roots);
+#endif
 	
 	CDDM_apply_vert_coords(psys->hair_out_dm, deformedVerts);
 	
@@ -3210,7 +3473,14 @@ static void hair_step(ParticleSimulationData *sim, float cfra)
 	ParticleSystem *psys = sim->psys;
 	ParticleSettings *part = psys->part;
 	PARTICLE_P;
+	PARTICLE_PSMD;
 	float disp = psys_get_current_display_percentage(psys);
+	float *shapekey_data = NULL, *shapekey;
+	int totshapekey;
+
+	if (part->type == PART_HAIR) {
+		shapekey = shapekey_data = BKE_key_evaluate_particles(sim->ob, sim->psys, sim->scene ? sim->scene->r.cfra : 0.0f, &totshapekey);
+	}
 
 	LOOP_PARTICLES {
 		pa->size = part->size;
@@ -3221,8 +3491,35 @@ static void hair_step(ParticleSimulationData *sim, float cfra)
 			pa->flag |= PARS_NO_DISP;
 		else
 			pa->flag &= ~PARS_NO_DISP;
+
+		if (part->type == PART_HAIR) {
+			float hairmat[4][4];
+			HairKey *hkey;
+			int k;
+			
+			psys_mat_hair_to_global(sim->ob, psmd->dm, psys->part->from, pa, hairmat);
+			
+			/* update world coordinates and calculate shapekey result if needed */
+			for (k = 0, hkey = pa->hair; k < pa->totkey; ++k, ++hkey) {
+				const float *co;
+				if (shapekey) {
+					co = shapekey;
+					shapekey += 3;
+					
+					copy_v3_v3(hkey->co, co);
+				}
+				else {
+					co = hkey->co;
+				}
+				
+				mul_v3_m4v3(hkey->world_co, hairmat, co);
+			}
+		}
 	}
 
+	if (shapekey_data)
+		MEM_freeN(shapekey_data);
+
 	if (psys->recalc & PSYS_RECALC_RESET) {
 		/* need this for changing subsurf levels */
 		psys_calc_dmcache(sim->ob, sim->psmd->dm, psys);