Merge remote-tracking branch 'bp/master'

.gitignore

@@ -19,3 +19,14 @@ pip-selfcheck.json
 /build
 /dist
 *.eggs
+
+# CMake
+CMakeFiles/
+CMakeCache.txt
+cmake_install.cmake
+CTestTestFile.cmake
+
+# Visual Studio build files
+*.vcxproj
+*.vcxproj.filters
+*.sln

examples/SharedMemory/PhysicsClientC_API.cpp

@@ -422,11 +422,12 @@ B3_SHARED_API int b3LoadSoftBodySetFrictionCoefficient(b3SharedMemoryCommandHand
 	return 0;
 }
 
-B3_SHARED_API int b3LoadSoftBodyUseBendingSprings(b3SharedMemoryCommandHandle commandHandle, int useBendingSprings)
+B3_SHARED_API int b3LoadSoftBodyUseBendingSprings(b3SharedMemoryCommandHandle commandHandle, int useBendingSprings, double bendingStiffness)
 {
 	struct SharedMemoryCommand* command = (struct SharedMemoryCommand*)commandHandle;
 	b3Assert(command->m_type == CMD_LOAD_SOFT_BODY);
     command->m_loadSoftBodyArguments.m_useBendingSprings = useBendingSprings;
+    command->m_loadSoftBodyArguments.m_springBendingStiffness = bendingStiffness;
 	command->m_updateFlags |= LOAD_SOFT_BODY_ADD_BENDING_SPRINGS;
 	return 0;
 }

examples/SharedMemory/PhysicsClientC_API.h

@@ -643,7 +643,7 @@ extern "C"
 	B3_SHARED_API int b3LoadSoftBodySetSelfCollision(b3SharedMemoryCommandHandle commandHandle, int useSelfCollision);
     B3_SHARED_API int b3LoadSoftBodyUseFaceContact(b3SharedMemoryCommandHandle commandHandle, int useFaceContact);
 	B3_SHARED_API int b3LoadSoftBodySetFrictionCoefficient(b3SharedMemoryCommandHandle commandHandle, double frictionCoefficient);
-	B3_SHARED_API int b3LoadSoftBodyUseBendingSprings(b3SharedMemoryCommandHandle commandHandle, int useBendingSprings);
+	B3_SHARED_API int b3LoadSoftBodyUseBendingSprings(b3SharedMemoryCommandHandle commandHandle, int useBendingSprings, double bendingStiffness);
 	
 	B3_SHARED_API b3SharedMemoryCommandHandle b3InitCreateSoftBodyAnchorConstraintCommand(b3PhysicsClientHandle physClient, int softBodyUniqueId, int nodeIndex, int bodyUniqueId, int linkIndex, const double bodyFramePosition[3]);
 

examples/SharedMemory/PhysicsServerCommandProcessor.cpp

@@ -8069,7 +8069,7 @@ bool PhysicsServerCommandProcessor::processLoadSoftBodyCommand(const struct Shar
 	{
 		collisionMargin = clientCmd.m_loadSoftBodyArguments.m_collisionMargin;
 	}
-        
+    btScalar spring_bending_stiffness = 0;
 	{
         btSoftBody* psb = NULL;
         
@@ -8144,7 +8144,11 @@ bool PhysicsServerCommandProcessor::processLoadSoftBodyCommand(const struct Shar
 			{
 				spring_elastic_stiffness = clientCmd.m_loadSoftBodyArguments.m_springElasticStiffness;
 				spring_damping_stiffness = clientCmd.m_loadSoftBodyArguments.m_springDampingStiffness;
-				btDeformableLagrangianForce* springForce = new btDeformableMassSpringForce(spring_elastic_stiffness, spring_damping_stiffness, false);
+                if (clientCmd.m_updateFlags & LOAD_SOFT_BODY_ADD_BENDING_SPRINGS)
+                {
+                    spring_bending_stiffness = clientCmd.m_loadSoftBodyArguments.m_springBendingStiffness;
+                }
+				btDeformableLagrangianForce* springForce = new btDeformableMassSpringForce(spring_elastic_stiffness, spring_damping_stiffness, false, spring_bending_stiffness);
 				deformWorld->addForce(psb, springForce);
 				m_data->m_lf.push_back(springForce);
 			}
@@ -8182,7 +8186,11 @@ bool PhysicsServerCommandProcessor::processLoadSoftBodyCommand(const struct Shar
 				{
 					spring_elastic_stiffness = clientCmd.m_loadSoftBodyArguments.m_springElasticStiffness;
 					spring_damping_stiffness = clientCmd.m_loadSoftBodyArguments.m_springDampingStiffness;
-					btDeformableLagrangianForce* springForce = new btDeformableMassSpringForce(spring_elastic_stiffness, spring_damping_stiffness, true);
+                    if (clientCmd.m_updateFlags & LOAD_SOFT_BODY_ADD_BENDING_SPRINGS)
+                    {
+                        spring_bending_stiffness = clientCmd.m_loadSoftBodyArguments.m_springBendingStiffness;
+                    }
+					btDeformableLagrangianForce* springForce = new btDeformableMassSpringForce(spring_elastic_stiffness, spring_damping_stiffness, true, spring_bending_stiffness);
 					deformWorld->addForce(psb, springForce);
 					m_data->m_lf.push_back(springForce);
 				}
@@ -8257,18 +8265,17 @@ bool PhysicsServerCommandProcessor::processLoadSoftBodyCommand(const struct Shar
                     friction_coeff = loadSoftBodyArgs.m_frictionCoeff;
             }
             psb->m_cfg.kDF = friction_coeff;
-            
+            bool use_bending_spring = false;
-            bool use_bending_spring = true;
             if (clientCmd.m_updateFlags & LOAD_SOFT_BODY_ADD_BENDING_SPRINGS)
             {
                 use_bending_spring = loadSoftBodyArgs.m_useBendingSprings;
+                if (use_bending_spring)
+                {
+                    psb->generateBendingConstraints(2);
+                }
             }
             btSoftBody::Material* pm = psb->appendMaterial();
             pm->m_flags -= btSoftBody::fMaterial::DebugDraw;
-            if (use_bending_spring)
-            {
-                    psb->generateBendingConstraints(2,pm);
-            }
             
             // turn on the collision flag for deformable
             // collision between deformable and rigid

examples/SharedMemory/SharedMemoryCommands.h

@@ -526,6 +526,7 @@ struct LoadSoftBodyArgs
     double m_initialOrientation[4];
     double m_springElasticStiffness;
     double m_springDampingStiffness;
+    double m_springBendingStiffness;
     double m_corotatedMu;
     double m_corotatedLambda;
     int m_useBendingSprings;

examples/SharedMemory/SharedMemoryPublic.h

@@ -7,8 +7,8 @@
 //Please don't replace an existing magic number:
 //instead, only ADD a new one at the top, comment-out previous one
 
-
+#define SHARED_MEMORY_MAGIC_NUMBER 201911280
-#define SHARED_MEMORY_MAGIC_NUMBER 201911180
+//#define SHARED_MEMORY_MAGIC_NUMBER 201911180
 //#define SHARED_MEMORY_MAGIC_NUMBER 201909030
 //#define SHARED_MEMORY_MAGIC_NUMBER 201908110
 //#define SHARED_MEMORY_MAGIC_NUMBER 201908050

examples/pybullet/pybullet.c

@@ -1973,7 +1973,7 @@ static PyObject* pybullet_loadSoftBody(PyObject* self, PyObject* args, PyObject*
 	int physicsClientId = 0;
 	int flags = 0;
 
-	static char* kwlist[] = {"fileName", "basePosition", "baseOrientation", "scale", "mass", "collisionMargin", "physicsClientId", "useMassSpring", "useBendingSprings", "useNeoHookean", "springElasticStiffness", "springDampingStiffness", "NeoHookeanMu", "NeoHookeanLambda", "NeoHookeanDamping", "frictionCoeff", "useFaceContact", "useSelfCollision", NULL};
+	static char* kwlist[] = {"fileName", "basePosition", "baseOrientation", "scale", "mass", "collisionMargin", "physicsClientId", "useMassSpring", "useBendingSprings", "useNeoHookean", "springElasticStiffness", "springDampingStiffness", "springBendingStiffness", "NeoHookeanMu", "NeoHookeanLambda", "NeoHookeanDamping", "frictionCoeff", "useFaceContact", "useSelfCollision", NULL};
 
 	int bodyUniqueId = -1;
 	const char* fileName = "";
@@ -1985,6 +1985,7 @@ static PyObject* pybullet_loadSoftBody(PyObject* self, PyObject* args, PyObject*
 	int useNeoHookean = 0;
 	double springElasticStiffness = 1;
 	double springDampingStiffness = 0.1;
+	double springBendingStiffness = 0.1;
 	double NeoHookeanMu = 1;
 	double NeoHookeanLambda = 1;
 	double NeoHookeanDamping = 0.1;
@@ -2002,7 +2003,7 @@ static PyObject* pybullet_loadSoftBody(PyObject* self, PyObject* args, PyObject*
 	PyObject* basePosObj = 0;
 	PyObject* baseOrnObj = 0;
 
-	if (!PyArg_ParseTupleAndKeywords(args, keywds, "s|OOdddiiiiddddddii", kwlist, &fileName, &basePosObj, &baseOrnObj, &scale, &mass, &collisionMargin, &physicsClientId, &useMassSpring, &useBendingSprings, &useNeoHookean, &springElasticStiffness, &springDampingStiffness, &NeoHookeanMu, &NeoHookeanLambda, &NeoHookeanDamping, &frictionCoeff, &useFaceContact, &useSelfCollision))
+	if (!PyArg_ParseTupleAndKeywords(args, keywds, "s|OOdddiiiidddddddii", kwlist, &fileName, &basePosObj, &baseOrnObj, &scale, &mass, &collisionMargin, &physicsClientId, &useMassSpring, &useBendingSprings, &useNeoHookean, &springElasticStiffness, &springDampingStiffness, &springBendingStiffness, &NeoHookeanMu, &NeoHookeanLambda, &NeoHookeanDamping, &frictionCoeff, &useFaceContact, &useSelfCollision))
 	{
 		return NULL;
 	}
@@ -2058,7 +2059,7 @@ static PyObject* pybullet_loadSoftBody(PyObject* self, PyObject* args, PyObject*
 		if (useMassSpring)
 		{
 			b3LoadSoftBodyAddMassSpringForce(command, springElasticStiffness, springDampingStiffness);
-			b3LoadSoftBodyUseBendingSprings(command, useBendingSprings);
+			b3LoadSoftBodyUseBendingSprings(command, useBendingSprings, springBendingStiffness);
 		}
 		if (useNeoHookean)
 		{

src/BulletSoftBody/btDeformableMassSpringForce.h

@@ -23,14 +23,18 @@ class btDeformableMassSpringForce : public btDeformableLagrangianForce
     // If true, the damping force will be in the direction of the spring
     // If false, the damping force will be in the direction of the velocity
     bool m_momentum_conserving;
-    btScalar m_elasticStiffness, m_dampingStiffness;
+    btScalar m_elasticStiffness, m_dampingStiffness, m_bendingStiffness;
 public:
     typedef btAlignedObjectArray<btVector3> TVStack;
     btDeformableMassSpringForce() : m_momentum_conserving(false), m_elasticStiffness(1), m_dampingStiffness(0.05)
     {
     }
-    btDeformableMassSpringForce(btScalar k, btScalar d, bool conserve_angular = true) : m_momentum_conserving(conserve_angular), m_elasticStiffness(k), m_dampingStiffness(d)
+    btDeformableMassSpringForce(btScalar k, btScalar d, bool conserve_angular = true, double bending_k = -1) : m_momentum_conserving(conserve_angular), m_elasticStiffness(k), m_dampingStiffness(d), m_bendingStiffness(bending_k)
     {
+        if (m_bendingStiffness < btScalar(0))
+        {
+            m_bendingStiffness = m_elasticStiffness;
+        }
     }
     
     virtual void addScaledForces(btScalar scale, TVStack& force)
@@ -103,7 +107,8 @@ public:
                 // elastic force
                 btVector3 dir = (node2->m_q - node1->m_q);
                 btVector3 dir_normalized = (dir.norm() > SIMD_EPSILON) ? dir.normalized() : btVector3(0,0,0);
-                btVector3 scaled_force = scale * m_elasticStiffness * (dir - dir_normalized * r);
+                btScalar scaled_stiffness = scale * (link.m_bbending ? m_bendingStiffness : m_elasticStiffness);
+                btVector3 scaled_force = scaled_stiffness * (dir - dir_normalized * r);
                 force[id1] += scaled_force;
                 force[id2] -= scaled_force;
             }
@@ -212,7 +217,6 @@ public:
             {
                 continue;
             }
-            btScalar scaled_k = m_elasticStiffness * scale;
             for (int j = 0; j < psb->m_links.size(); ++j)
             {
                 const btSoftBody::Link& link = psb->m_links[j];
@@ -227,6 +231,7 @@ public:
                 btVector3 dir_normalized = (dir_norm > SIMD_EPSILON) ? dir.normalized() : btVector3(0,0,0);
                 btVector3 dx_diff = dx[id1] - dx[id2];
                 btVector3 scaled_df = btVector3(0,0,0);
+                btScalar scaled_k = scale * (link.m_bbending ? m_bendingStiffness : m_elasticStiffness);
                 if (dir_norm > SIMD_EPSILON)
                 {
                     scaled_df -= scaled_k * dir_normalized.dot(dx_diff) * dir_normalized;