[Bf-blender-cvs] [dd0a744] master: Main cloth force calculation function outside of implicit core code.

Lukas Tönne noreply at git.blender.org
Tue Jan 20 09:50:43 CET 2015


Commit: dd0a7444d8e2bd3366fb91710bf4349aa5b69351
Author: Lukas Tönne
Date:   Sun Sep 14 19:36:33 2014 +0200
Branches: master
https://developer.blender.org/rBdd0a7444d8e2bd3366fb91710bf4349aa5b69351

Main cloth force calculation function outside of implicit core code.

Still misses spring forces.

===================================================================

M	source/blender/physics/intern/BPH_mass_spring.cpp
M	source/blender/physics/intern/implicit.h
M	source/blender/physics/intern/implicit_blender.c

===================================================================

diff --git a/source/blender/physics/intern/BPH_mass_spring.cpp b/source/blender/physics/intern/BPH_mass_spring.cpp
index 5c5fffb..abff8f9 100644
--- a/source/blender/physics/intern/BPH_mass_spring.cpp
+++ b/source/blender/physics/intern/BPH_mass_spring.cpp
@@ -34,6 +34,7 @@ extern "C" {
 
 #include "DNA_cloth_types.h"
 #include "DNA_scene_types.h"
+#include "DNA_object_force.h"
 #include "DNA_object_types.h"
 #include "DNA_meshdata_types.h"
 #include "DNA_modifier_types.h"
@@ -319,6 +320,93 @@ static int UNUSED_FUNCTION(cloth_calc_helper_forces)(Object *UNUSED(ob), ClothMo
 	return 1;
 }
 
+static void cloth_calc_force(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};
+	MFace 		*mfaces 	= cloth->mfaces;
+	unsigned int numverts = cloth->numverts;
+	
+	/* initialize forces to zero */
+	BPH_mass_spring_force_clear(data);
+	
+#ifdef CLOTH_FORCE_GRAVITY
+	/* global acceleration (gravitation) */
+	if (clmd->scene->physics_settings.flag & PHYS_GLOBAL_GRAVITY) {
+		/* scale gravity force */
+		mul_v3_v3fl(gravity, clmd->scene->physics_settings.gravity, 0.001f * clmd->sim_parms->effector_weights->global_gravity);
+	}
+	BPH_mass_spring_force_gravity(data, gravity);
+#else
+	zero_lfvector(lF, numverts);
+#endif
+
+	// XXX TODO
+//	hair_volume_forces(clmd, lF, lX, lV, numverts);
+
+#ifdef CLOTH_FORCE_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 * numverts, "effector forces");
+		for (i = 0; i < cloth->numverts; i++) {
+			float x[3], v[3];
+			EffectedPoint epoint;
+			
+			BPH_mass_spring_get_motion_state(data, i, x, v);
+			pd_point_from_loc(clmd->scene, x, v, i, &epoint);
+			pdDoEffectors(effectors, NULL, clmd->sim_parms->effector_weights, &epoint, winvec[i], NULL);
+		}
+		
+		for (i = 0; i < cloth->numfaces; i++) {
+			MFace *mf = &mfaces[i];
+			BPH_mass_spring_force_face_wind(data, mf->v1, mf->v2, mf->v3, mf->v4, winvec);
+		}
+
+		/* Hair has only edges */
+		if (cloth->numfaces == 0) {
+			for (LinkNode *link = cloth->springs; link; link = link->next) {
+				ClothSpring *spring = (ClothSpring *)link->link;
+				if (spring->type == CLOTH_SPRING_TYPE_STRUCTURAL)
+					BPH_mass_spring_force_edge_wind(data, spring->ij, spring->kl, winvec);
+			}
+		}
+
+		MEM_freeN(winvec);
+	}
+	
+#if 0
+	// calculate spring forces
+	link = cloth->springs;
+	while (link) {
+		// only handle active springs
+		ClothSpring *spring = link->link;
+		if (!(spring->flags & CLOTH_SPRING_FLAG_DEACTIVATE))
+			cloth_calc_spring_force(clmd, link->link, lF, lX, lV, dFdV, dFdX, time);
+
+		link = link->next;
+	}
+	
+	// apply spring forces
+	link = cloth->springs;
+	while (link) {
+		// only handle active springs
+		ClothSpring *spring = link->link;
+		if (!(spring->flags & CLOTH_SPRING_FLAG_DEACTIVATE))
+			cloth_apply_spring_force(clmd, link->link, lF, lX, lV, dFdV, dFdX);
+		link = link->next;
+	}
+	// printf("\n");
+#endif
+}
+
 int BPH_cloth_solve(Object *ob, float frame, ClothModifierData *clmd, ListBase *effectors)
 {
 	unsigned int i=0;
@@ -381,7 +469,7 @@ int BPH_cloth_solve(Object *ob, float frame, ClothModifierData *clmd, ListBase *
 		}
 		
 		// calculate forces
-//		cloth_calc_force(clmd, frame, id->F, id->X, id->V, id->dFdV, id->dFdX, effectors, step, id->M);
+		cloth_calc_force(clmd, frame, effectors, step);
 		
 		// calculate new velocity and position
 		BPH_mass_spring_solve(id, dt);
diff --git a/source/blender/physics/intern/implicit.h b/source/blender/physics/intern/implicit.h
index d203671..c9e8fb2 100644
--- a/source/blender/physics/intern/implicit.h
+++ b/source/blender/physics/intern/implicit.h
@@ -118,6 +118,12 @@ void BPH_mass_spring_add_constraint_ndof2(struct Implicit_Data *data, int index,
 bool BPH_mass_spring_solve(struct Implicit_Data *data, float dt);
 void BPH_mass_spring_apply_result(struct Implicit_Data *data);
 
+void BPH_mass_spring_force_clear(struct Implicit_Data *data);
+void BPH_mass_spring_force_gravity(struct Implicit_Data *data, const float g[3]);
+void BPH_mass_spring_force_drag(struct Implicit_Data *data, float drag);
+void BPH_mass_spring_force_face_wind(struct Implicit_Data *data, int v1, int v2, int v3, int v4, const float (*winvec)[3]);
+void BPH_mass_spring_force_edge_wind(struct Implicit_Data *data, int v1, int v2, const float (*winvec)[3]);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/blender/physics/intern/implicit_blender.c b/source/blender/physics/intern/implicit_blender.c
index 90d7eee..fb90b3a 100644
--- a/source/blender/physics/intern/implicit_blender.c
+++ b/source/blender/physics/intern/implicit_blender.c
@@ -1528,227 +1528,6 @@ DO_INLINE void cloth_apply_spring_force(ClothModifierData *UNUSED(clmd), ClothSp
 	}
 }
 
-
-static void CalcFloat( float *v1, float *v2, float *v3, float *n)
-{
-	float n1[3], n2[3];
-
-	n1[0] = v1[0]-v2[0];
-	n2[0] = v2[0]-v3[0];
-	n1[1] = v1[1]-v2[1];
-	n2[1] = v2[1]-v3[1];
-	n1[2] = v1[2]-v2[2];
-	n2[2] = v2[2]-v3[2];
-	n[0] = n1[1]*n2[2]-n1[2]*n2[1];
-	n[1] = n1[2]*n2[0]-n1[0]*n2[2];
-	n[2] = n1[0]*n2[1]-n1[1]*n2[0];
-}
-
-static void CalcFloat4( float *v1, float *v2, float *v3, float *v4, float *n)
-{
-	/* real cross! */
-	float n1[3], n2[3];
-
-	n1[0] = v1[0]-v3[0];
-	n1[1] = v1[1]-v3[1];
-	n1[2] = v1[2]-v3[2];
-
-	n2[0] = v2[0]-v4[0];
-	n2[1] = v2[1]-v4[1];
-	n2[2] = v2[2]-v4[2];
-
-	n[0] = n1[1]*n2[2]-n1[2]*n2[1];
-	n[1] = n1[2]*n2[0]-n1[0]*n2[2];
-	n[2] = n1[0]*n2[1]-n1[1]*n2[0];
-}
-
-static float calculateVertexWindForce(const float wind[3], const float vertexnormal[3])
-{
-	return dot_v3v3(wind, vertexnormal);
-}
-
-static void cloth_calc_force(ClothModifierData *clmd, float UNUSED(frame), lfVector *lF, lfVector *lX, lfVector *lV, fmatrix3x3 *dFdV, fmatrix3x3 *dFdX, ListBase *effectors, float time, fmatrix3x3 *M)
-{
-	/* Collect forces and derivatives:  F, dFdX, dFdV */
-	Cloth 		*cloth 		= clmd->clothObject;
-	ClothVertex *verts = cloth->verts;
-	RootTransform *roots = cloth->implicit->root;
-	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};
-	MFace 		*mfaces 	= cloth->mfaces;
-	unsigned int numverts = cloth->numverts;
-	LinkNode *search;
-	lfVector *winvec;
-	EffectedPoint epoint;
-	
-	/* initialize forces to zero */
-	zero_lfvector(lF, numverts);
-	init_bfmatrix(dFdX, ZERO);
-	init_bfmatrix(dFdV, ZERO);
-
-#ifdef CLOTH_FORCE_GRAVITY
-	/* global acceleration (gravitation) */
-	if (clmd->scene->physics_settings.flag & PHYS_GLOBAL_GRAVITY) {
-		copy_v3_v3(gravity, clmd->scene->physics_settings.gravity);
-		mul_fvector_S(gravity, gravity, 0.001f * clmd->sim_parms->effector_weights->global_gravity); /* scale gravity force */
-	}
-	/* multiply lF with mass matrix
-	 * force = mass * acceleration (in this case: gravity)
-	 */
-	for (i = 0; i < numverts; i++) {
-		float g[3];
-		acc_world_to_root(g, lX[i], lV[i], gravity, &roots[i]);
-		mul_m3_v3(M[i].m, g);
-		add_v3_v3(lF[i], g);
-	}
-#else
-	zero_lfvector(lF, numverts);
-#endif
-
-	// XXX TODO
-//	hair_volume_forces(clmd, lF, lX, lV, numverts);
-
-#ifdef CLOTH_FORCE_DRAG
-	/* set dFdX jacobi matrix diagonal entries to -spring_air */ 
-	for (i = 0; i < numverts; i++) {
-		dFdV[i].m[0][0] -= drag;
-		dFdV[i].m[1][1] -= drag;
-		dFdV[i].m[2][2] -= drag;
-	}
-	submul_lfvectorS(lF, lV, drag, numverts);
-	for (i = 0; i < numverts; i++) {
-#if 1
-		float tmp[3][3];
-		
-		/* NB: uses root space velocity, no need to transform */
-		madd_v3_v3fl(lF[i], lV[i], -drag);
-		
-		copy_m3_m3(tmp, I);
-		mul_m3_fl(tmp, -drag);
-		add_m3_m3m3(dFdV[i].m, dFdV[i].m, tmp);
-#else
-		float f[3], tmp[3][3], drag_dfdv[3][3], t[3];
-		
-		mul_v3_v3fl(f, lV[i], -drag);
-		force_world_to_root(t, lX[i], lV[i], f, verts[i].mass, &roots[i]);
-		add_v3_v3(lF[i], t);
-		
-		copy_m3_m3(drag_dfdv, I);
-		mul_m3_fl(drag_dfdv, -drag);
-		dfdv_world_to_root(tmp, drag_dfdv, verts[i].mass, &roots[i]);
-		add_m3_m3m3(dFdV[i].m, dFdV[i].m, tmp);
-#endif
-	}
-#endif
-	
-	/* handle external forces like wind */
-	if (effectors) {
-		// 0 = force, 1 = normalized force
-		winvec = create_lfvector(cloth->numverts);
-		
-		if (!winvec)
-			printf("winvec: out of memory in implicit.c\n");
-		
-		// precalculate wind forces
-		for (i = 0; i < cloth->numverts; i++) {
-			pd_point_from_loc(clmd->scene, (float*)lX[i], (float*)lV[i], i, &epoint);
-			pdDoEffectors(effectors, NULL, clmd->sim_parms->effector_weights, &epoint, winvec[i], NULL);
-		}
-		
-		for (i = 0; i < cloth->numfaces; i++) {
-			float trinormal[3] = {0, 0, 0}; // normalized triangle normal
-			float triunnormal[3] = {0, 0, 0}; // not-normalized-triangle normal
-			float tmp[3] = {0, 0, 0};
-			float factor = (mfaces[i].v4) ? 0.25 : 1.0 / 3.0;
-			factor *= 0.02f;
-			
-			// calculate face normal
-			if (mfaces[i].v4)
-				CalcFloat4(lX[mfaces[i].v1], lX[mfaces[i].v2], lX[mfaces[i].v3], lX[mfaces[i].v4], triunnormal);
-			else
-				CalcFloat(lX[mfaces[i].v1], lX[mfaces[i].v2], lX[mfaces[i].v3], triunnormal);
-
-			normalize_v3_v3(trinormal, triunnormal);
-			
-			// add wind from v1
-			copy_v3_v3(tmp, trinormal);
-			mul_v3_fl(tmp, calculateVertexWindForce(winvec[mfaces[i].v1], triunnormal));
-			VECADDS(lF[mfaces[i].v1], lF[mfaces[i].v1], tmp, factor);
-			
-			// add wind from v2
-			copy_v3_v3(tmp, trinormal);
-			mul_v3_fl(tmp, calculateVertexWindForce(winvec[mfaces[i].v2], triunnormal));
-			VECADDS(lF[mfaces[i].v2], lF[mfaces[i].v2], tmp, factor);
-			
-			// add wind from v3
-			copy_v3_v3(tmp, trinormal);
-			mul_v3_fl(tmp, calculateVertexWindForce(winvec[mfaces[i].v3], triunnormal));
-			VECADDS(lF[mfaces[i].v3], lF[mfaces[i].v3], tmp, factor);
-			
-			// add wind from v4
-			if (mfaces[i].v4) {
-				copy_v3_v3(tmp, trinormal);
-				mul_v3_fl(tmp, calculateVertexWindForce(winvec[mface

@@ Diff output truncated at 10240 characters. @@




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