support concave soft bodies, preliminary. could be used for cloth too. need vertex pinning/constraint attach to other objects.

extern/bullet2/src/BulletCollision/CollisionShapes/btTriangleMesh.cpp

@@ -19,7 +19,8 @@ subject to the following restrictions:
 
 btTriangleMesh::btTriangleMesh (bool use32bitIndices,bool use4componentVertices)
 :m_use32bitIndices(use32bitIndices),
-m_use4componentVertices(use4componentVertices)
+m_use4componentVertices(use4componentVertices),
+m_weldingThreshold(0.0)
 {
 	btIndexedMesh meshIndex;
 	meshIndex.m_numTriangles = 0;
@@ -60,49 +61,66 @@ m_use4componentVertices(use4componentVertices)
 
 }
 
+void	btTriangleMesh::addIndex(int index)
+{
+	if (m_use32bitIndices)
+	{
+		m_32bitIndices.push_back(index);
+		m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_32bitIndices[0];
+	} else
+	{
+		m_16bitIndices.push_back(index);
+		m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_16bitIndices[0];
+	}
+}
+
+int	btTriangleMesh::findOrAddVertex(const btVector3& vertex)
+{
+	//return index of new/existing vertex
+	//todo: could use acceleration structure for this
+	if (m_use4componentVertices)
+	{
+		for (int i=0;i< m_4componentVertices.size();i++)
+		{
+			if ((m_4componentVertices[i]-vertex).length2() <= m_weldingThreshold)
+			{
+				return i;
+			}
+		}
+		m_indexedMeshes[0].m_numVertices++;
+		m_4componentVertices.push_back(vertex);
+		m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_4componentVertices[0];
+
+		return m_4componentVertices.size()-1;
+		
+	} else
+	{
+		
+		for (int i=0;i< m_3componentVertices.size();i+=3)
+		{
+			btVector3 vtx(m_3componentVertices[i],m_3componentVertices[i+1],m_3componentVertices[i+2]);
+			if ((vtx-vertex).length2() <= m_weldingThreshold)
+			{
+				return i/3;
+			}
+		}
+		m_3componentVertices.push_back(vertex.getX());
+		m_3componentVertices.push_back(vertex.getY());
+		m_3componentVertices.push_back(vertex.getZ());
+		m_indexedMeshes[0].m_numVertices++;
+		m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_3componentVertices[0];
+		return (m_3componentVertices.size()/3)-1;
+	}
+
+}
 		
 void	btTriangleMesh::addTriangle(const btVector3& vertex0,const btVector3& vertex1,const btVector3& vertex2)
 {
 	m_indexedMeshes[0].m_numTriangles++;
-	m_indexedMeshes[0].m_numVertices+=3;
+		
-
+	addIndex(findOrAddVertex(vertex0));
-	if (m_use4componentVertices)
+	addIndex(findOrAddVertex(vertex1));
-	{
+	addIndex(findOrAddVertex(vertex2));
-		m_4componentVertices.push_back(vertex0);
-		m_4componentVertices.push_back(vertex1);
-		m_4componentVertices.push_back(vertex2);
-		m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_4componentVertices[0];
-	} else
-	{
-		m_3componentVertices.push_back(vertex0.getX());
-		m_3componentVertices.push_back(vertex0.getY());
-		m_3componentVertices.push_back(vertex0.getZ());
-
-		m_3componentVertices.push_back(vertex1.getX());
-		m_3componentVertices.push_back(vertex1.getY());
-		m_3componentVertices.push_back(vertex1.getZ());
-
-		m_3componentVertices.push_back(vertex2.getX());
-		m_3componentVertices.push_back(vertex2.getY());
-		m_3componentVertices.push_back(vertex2.getZ());
-		m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_3componentVertices[0];
-	}
-
-	if (m_use32bitIndices)
-	{
-		int curIndex = m_32bitIndices.size();
-		m_32bitIndices.push_back(curIndex++);
-		m_32bitIndices.push_back(curIndex++);
-		m_32bitIndices.push_back(curIndex++);
-		m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_32bitIndices[0];
-	} else
-	{
-		short curIndex = static_cast<short>(m_16bitIndices.size());
-		m_16bitIndices.push_back(curIndex++);
-		m_16bitIndices.push_back(curIndex++);
-		m_16bitIndices.push_back(curIndex++);
-		m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_16bitIndices[0];
-	}
 }
 
 int btTriangleMesh::getNumTriangles() const

extern/bullet2/src/BulletCollision/CollisionShapes/btTriangleMesh.h

@@ -25,6 +25,7 @@ subject to the following restrictions:
 ///It allows either 32bit or 16bit indices, and 4 (x-y-z-w) or 3 (x-y-z) component vertices.
 ///If you want to share triangle/index data between graphics mesh and collision mesh (btBvhTriangleMeshShape), you can directly use btTriangleIndexVertexArray or derive your own class from btStridingMeshInterface.
 ///Performance of btTriangleMesh and btTriangleIndexVertexArray used in a btBvhTriangleMeshShape is the same.
+///It has a brute-force option to weld together closeby vertices.
 class btTriangleMesh : public btTriangleIndexVertexArray
 {
 	btAlignedObjectArray<btVector3>	m_4componentVertices;
@@ -34,11 +35,16 @@ class btTriangleMesh : public btTriangleIndexVertexArray
 	btAlignedObjectArray<unsigned short int>		m_16bitIndices;
 	bool	m_use32bitIndices;
 	bool	m_use4componentVertices;
-
+	
 
 	public:
+		btScalar	m_weldingThreshold;
+
 		btTriangleMesh (bool use32bitIndices=true,bool use4componentVertices=true);
 
+		int		findOrAddVertex(const btVector3& vertex);
+		void	addIndex(int index);
+
 		bool	getUse32bitIndices() const
 		{
 			return m_use32bitIndices;

source/gameengine/Ketsji/KX_ConvertPhysicsObjects.cpp

@@ -881,6 +881,9 @@ void	KX_ConvertBulletObject(	class	KX_GameObject* gameobj,
 				{
 					shapeInfo->SetMesh(meshobj, false,false);
 				}
+				if (objprop->m_softbody)
+					shapeInfo->setVertexWeldingThreshold(0.01f); //todo: expose this to the UI
+
 				bm = shapeInfo->CreateBulletShape();
 				//no moving concave meshes, so don't bother calculating inertia
 				//bm->calculateLocalInertia(ci.m_mass,ci.m_localInertiaTensor);

source/gameengine/Physics/Bullet/CcdPhysicsController.cpp

@@ -160,9 +160,9 @@ void CcdPhysicsController::CreateRigidbody()
 
 	//disable soft body until first sneak preview is ready
 	if (m_cci.m_bSoft && m_cci.m_collisionShape && 
-		(shapeType == CONVEX_HULL_SHAPE_PROXYTYPE))
+		(shapeType == CONVEX_HULL_SHAPE_PROXYTYPE)|
-		//(shapeType == TRIANGLE_MESH_SHAPE_PROXYTYPE) |
+		(shapeType == TRIANGLE_MESH_SHAPE_PROXYTYPE) |
-		//(shapeType == SCALED_TRIANGLE_MESH_SHAPE_PROXYTYPE)))
+		(shapeType == SCALED_TRIANGLE_MESH_SHAPE_PROXYTYPE))
 	{
 		btRigidBody::btRigidBodyConstructionInfo rbci(m_cci.m_mass,m_bulletMotionState,m_collisionShape,m_cci.m_localInertiaTensor * m_cci.m_inertiaFactor);
 		rbci.m_linearDamping = m_cci.m_linearDamping;
@@ -221,57 +221,7 @@ void CcdPhysicsController::CreateRigidbody()
 					psb->appendFace(idx[0],idx[1],idx[2]);
 				}
 				
-				///create a mapping between graphics mesh vertices and soft body vertices
+				
-				{
-					RAS_MeshObject* rasMesh= GetShapeInfo()->GetMesh();
-
-					if (rasMesh && !m_softbodyMappingDone)
-					{
-						
-						//printf("apply\n");
-						RAS_MeshSlot::iterator it;
-						RAS_MeshMaterial *mmat;
-						RAS_MeshSlot *slot;
-						size_t i;
-
-						//for each material
-						for (int m=0;m<rasMesh->NumMaterials();m++)
-						{
-							// The vertex cache can only be updated for this deformer:
-							// Duplicated objects with more than one ploymaterial (=multiple mesh slot per object)
-							// share the same mesh (=the same cache). As the rendering is done per polymaterial
-							// cycling through the objects, the entire mesh cache cannot be updated in one shot.
-							mmat = rasMesh->GetMeshMaterial(m);
-
-							slot = mmat->m_baseslot;
-							for(slot->begin(it); !slot->end(it); slot->next(it))
-							{
-								int index = 0;
-								for(i=it.startvertex; i<it.endvertex; i++,index++) 
-								{
-									RAS_TexVert* vertex = &it.vertex[i];
-									
-
-									//search closest index, and store it in vertex
-									vertex->setSoftBodyIndex(0);
-									btScalar maxDistSqr = 1e30;
-									btSoftBody::tNodeArray&   nodes(psb->m_nodes);
-									btVector3 xyz = btVector3(vertex->getXYZ()[0],vertex->getXYZ()[1],vertex->getXYZ()[2]);
-									for (int n=0;n<nodes.size();n++)
-									{
-										btScalar distSqr = (nodes[n].m_x - xyz).length2();
-										if (distSqr<maxDistSqr)
-										{
-											maxDistSqr = distSqr;
-											
-											vertex->setSoftBodyIndex(n);
-										}
-									}
-								}
-							}
-						}
-					}
-				}
 
 				hlib.ReleaseResult(hres);
 
@@ -285,7 +235,9 @@ void CcdPhysicsController::CreateRigidbody()
 
 		} else
 		{
-			/*
+			
+			btSoftBodyWorldInfo& sbi= softDynaWorld->getWorldInfo();
+
 			if (m_cci.m_collisionShape->getShapeType() ==SCALED_TRIANGLE_MESH_SHAPE_PROXYTYPE)
 			{
 				btScaledBvhTriangleMeshShape* scaledtrimeshshape = (btScaledBvhTriangleMeshShape*) m_cci.m_collisionShape;
@@ -328,16 +280,15 @@ void CcdPhysicsController::CreateRigidbody()
 
 				//psb = btSoftBodyHelpers::CreateFromTriMesh(sbi,&pts[0].getX(),triangles,numtriangles);
 			}
-			*/
 
 		}
-		
+
-		m_softbodyMappingDone = true;
+	
 		
 		m_object = psb;
 
 		//psb->m_cfg.collisions	=	btSoftBody::fCollision::SDF_RS;//btSoftBody::fCollision::CL_SS+	btSoftBody::fCollision::CL_RS;
-		psb->m_cfg.collisions	=	btSoftBody::fCollision::SDF_RS + btSoftBody::fCollision::CL_SS;
+		psb->m_cfg.collisions	=	btSoftBody::fCollision::SDF_RS + btSoftBody::fCollision::VF_SS;//CL_SS;
 		//psb->m_cfg.collisions	=	btSoftBody::fCollision::CL_SS + btSoftBody::fCollision::CL_RS;
 		
 		//btSoftBody::Material*	pm=psb->appendMaterial();
@@ -352,10 +303,10 @@ void CcdPhysicsController::CreateRigidbody()
 		//pm->m_kAST = 0.01f;
 		//pm->m_kVST = 0.001f;
 		psb->generateBendingConstraints(2,pm);
-		//psb->m_cfg.piterations		=	4;
+		psb->m_cfg.piterations = 4;
-		//psb->m_cfg.viterations		=	4;
+		psb->m_cfg.viterations = 4;
-		//psb->m_cfg.diterations = 4;
+		psb->m_cfg.diterations = 4;
-		//psb->m_cfg.citerations = 4;
+		psb->m_cfg.citerations = 4;
 		if (m_cci.m_gamesoftFlag & 2)//OB_SB_GOAL)
 		{
 			psb->setPose(false,true);//
@@ -365,7 +316,7 @@ void CcdPhysicsController::CreateRigidbody()
 		}
 
 		psb->m_cfg.kDF				=	0.5;
-		psb->m_cfg.kMT				=	0.05;
+		//psb->m_cfg.kMT				=	0.05;
 		psb->m_cfg.piterations		=	5;
 		
 		psb->m_cfg.piterations		=	5;
@@ -392,8 +343,72 @@ void CcdPhysicsController::CreateRigidbody()
 		
 		//psb->m_materials[0]->m_kLST	=	0.1+(i/(btScalar)(n-1))*0.9;
 		psb->setTotalMass(m_cci.m_mass);
-		psb->generateClusters(8);//(64);		
+		psb->generateClusters(64);		
 		psb->setCollisionFlags(0);
+
+
+
+
+
+			///create a mapping between graphics mesh vertices and soft body vertices
+		{
+			RAS_MeshObject* rasMesh= GetShapeInfo()->GetMesh();
+
+			if (rasMesh && !m_softbodyMappingDone)
+			{
+				
+				//printf("apply\n");
+				RAS_MeshSlot::iterator it;
+				RAS_MeshMaterial *mmat;
+				RAS_MeshSlot *slot;
+				size_t i;
+
+				//for each material
+				for (int m=0;m<rasMesh->NumMaterials();m++)
+				{
+					// The vertex cache can only be updated for this deformer:
+					// Duplicated objects with more than one ploymaterial (=multiple mesh slot per object)
+					// share the same mesh (=the same cache). As the rendering is done per polymaterial
+					// cycling through the objects, the entire mesh cache cannot be updated in one shot.
+					mmat = rasMesh->GetMeshMaterial(m);
+
+					slot = mmat->m_baseslot;
+					for(slot->begin(it); !slot->end(it); slot->next(it))
+					{
+						int index = 0;
+						for(i=it.startvertex; i<it.endvertex; i++,index++) 
+						{
+							RAS_TexVert* vertex = &it.vertex[i];
+							
+
+							//search closest index, and store it in vertex
+							vertex->setSoftBodyIndex(0);
+							btScalar maxDistSqr = 1e30;
+							btSoftBody::tNodeArray&   nodes(psb->m_nodes);
+							btVector3 xyz = btVector3(vertex->getXYZ()[0],vertex->getXYZ()[1],vertex->getXYZ()[2]);
+							for (int n=0;n<nodes.size();n++)
+							{
+								btScalar distSqr = (nodes[n].m_x - xyz).length2();
+								if (distSqr<maxDistSqr)
+								{
+									maxDistSqr = distSqr;
+									
+									vertex->setSoftBodyIndex(n);
+								}
+							}
+						}
+					}
+				}
+			}
+		}
+		
+		m_softbodyMappingDone = true;
+
+
+
+
+
+
 //		m_object->setCollisionShape(rbci.m_collisionShape);
 		btTransform startTrans;
 
@@ -1391,6 +1406,8 @@ btCollisionShape* CcdShapeConstructionInfo::CreateBulletShape()
 		if (m_useGimpact)
 		{
 				collisionMeshData = new btTriangleMesh();
+				
+
 				// m_vertexArray is necessarily a multiple of 3
 				for (std::vector<btPoint3>::iterator it=m_vertexArray.begin(); it != m_vertexArray.end(); )
 				{
@@ -1405,7 +1422,9 @@ btCollisionShape* CcdShapeConstructionInfo::CreateBulletShape()
 		{
 			if (!m_unscaledShape)
 			{
-				collisionMeshData = new btTriangleMesh();
+				collisionMeshData = new btTriangleMesh(true,false);
+				collisionMeshData->m_weldingThreshold = m_weldingThreshold;
+
 				// m_vertexArray is necessarily a multiple of 3
 				for (std::vector<btPoint3>::iterator it=m_vertexArray.begin(); it != m_vertexArray.end(); )
 				{

source/gameengine/Physics/Bullet/CcdPhysicsController.h

@@ -43,6 +43,8 @@ class btCollisionShape;
 class CcdShapeConstructionInfo
 {
 public:
+	
+
 	static CcdShapeConstructionInfo* FindMesh(RAS_MeshObject* mesh, bool polytope);
 
 	CcdShapeConstructionInfo() :
@@ -54,7 +56,8 @@ public:
 		m_refCount(1),
 		m_meshObject(NULL),
 		m_unscaledShape(NULL),
-		m_useGimpact(false)
+		m_useGimpact(false),
+		m_weldingThreshold(0.f)
 	{
 		m_childTrans.setIdentity();
 	}
@@ -111,6 +114,14 @@ public:
 													// original mesh that correspond to shape triangles.
 													// only set for concave mesh shape.
 
+	void	setVertexWeldingThreshold(float threshold)
+	{
+		m_weldingThreshold  = threshold;
+	}
+	float	getVertexWeldingThreshold() const
+	{
+		return m_weldingThreshold;
+	}
 protected:
 	static std::map<RAS_MeshObject*, CcdShapeConstructionInfo*> m_meshShapeMap;
 	int						m_refCount;		// this class is shared between replicas
@@ -119,7 +130,9 @@ protected:
 	btBvhTriangleMeshShape* m_unscaledShape;// holds the shared unscale BVH mesh shape, 
 											// the actual shape is of type btScaledBvhTriangleMeshShape
 	std::vector<CcdShapeConstructionInfo*> m_shapeArray;	// for compound shapes
-	bool	m_useGimpact;
+	bool	m_useGimpact; //use gimpact for concave dynamic/moving collision detection
+	float	m_weldingThreshold;	//welding closeby vertices together can improve softbody stability etc.
+
 };
 
 struct CcdConstructionInfo