BGE : Fix crash during physics mesh update.

Currently we can't update the physics mesh of an added rigid body.
The cause is that that we need to update all shapes to say that the mesh was changed, for static object we don't do that previously because we use a odd way to reallocate memory at the same place.
So now when a mesh is changed we iterate all physics controllers which use the same shape info and recreate its shape with the correct mesh.

example file : {F168100}

Reviewers: scorpion81, sergof, hg1, sybren, moguri, agoose77

Reviewed By: moguri, agoose77

Subscribers: sybren

Differential Revision: https://developer.blender.org/D1269

source/gameengine/Physics/Bullet/CcdPhysicsController.cpp

@@ -39,7 +39,6 @@ subject to the following restrictions:
 #include "LinearMath/btConvexHull.h"
 #include "BulletCollision/Gimpact/btGImpactShape.h"
 
-
 #include "BulletSoftBody/btSoftRigidDynamicsWorld.h"
 
 #include "DNA_mesh_types.h"
@@ -599,20 +598,13 @@ void CcdPhysicsController::CreateRigidbody()
 
 static void DeleteBulletShape(btCollisionShape* shape, bool free)
 {
-	if (shape->getShapeType() == TRIANGLE_MESH_SHAPE_PROXYTYPE)
-	{
-		// shapes based on meshes use an interface that contains the vertices.
-		btTriangleMeshShape* meshShape = static_cast<btTriangleMeshShape*>(shape);
-		btStridingMeshInterface* meshInterface = meshShape->getMeshInterface();
-		if (meshInterface)
-			delete meshInterface;
-	}
-	else if (shape->getShapeType() == GIMPACT_SHAPE_PROXYTYPE)
-	{
-		btGImpactMeshShape* meshShape = static_cast<btGImpactMeshShape*>(shape);
-		btStridingMeshInterface* meshInterface = meshShape->getMeshInterface();
-		if (meshInterface)
-			delete meshInterface;
+	if (shape->getShapeType() == SCALED_TRIANGLE_MESH_SHAPE_PROXYTYPE) {
+		/* If we use Bullet scaled shape (btScaledBvhTriangleMeshShape) we have to
+		 * free the child of the unscaled shape (btTriangleMeshShape) here.
+		 */
+		btTriangleMeshShape *meshShape = ((btScaledBvhTriangleMeshShape *)shape)->getChildShape();
+		if (meshShape)
+			delete meshShape;
 	}
 	if (free) {
 		delete shape;
@@ -645,48 +637,41 @@ bool CcdPhysicsController::DeleteControllerShape( )
 
 bool CcdPhysicsController::ReplaceControllerShape(btCollisionShape *newShape)
 {
-	
-	/* Note, deleting the previous collision shape must be done already */
-	/* if (m_collisionShape) DeleteControllerShape(); */
+	if (m_collisionShape)
+		DeleteControllerShape();
+
+	// If newShape is NULL it means to create a new Bullet shape.
+	if (!newShape)
+		newShape = m_shapeInfo->CreateBulletShape(m_cci.m_margin, m_cci.m_bGimpact, !m_cci.m_bSoft);
 
 	m_object->setCollisionShape(newShape);
-	m_collisionShape= newShape;
-	m_cci.m_collisionShape= newShape;
-	
-	if (GetSoftBody()) {
+	m_collisionShape = newShape;
+	m_cci.m_collisionShape = newShape;
+
+	btSoftBody *softBody = GetSoftBody();
+	if (softBody) {
+		btSoftRigidDynamicsWorld *world = GetPhysicsEnvironment()->GetDynamicsWorld();
+		// remove the old softBody
+		world->removeSoftBody(softBody);
+
 		// soft body must be recreated
-		m_cci.m_physicsEnv->RemoveCcdPhysicsController(this);
 		delete m_object;
 		m_object = NULL;
 		// force complete reinitialization
 		m_softbodyMappingDone = false;
 		m_prototypeTransformInitialized = false;
 		m_softBodyTransformInitialized = false;
+
 		CreateSoftbody();
 		assert(m_object);
-		// reinsert the new body
-		m_cci.m_physicsEnv->AddCcdPhysicsController(this);
-	}
-	
-	/* Copied from CcdPhysicsEnvironment::addCcdPhysicsController() */
-	
-	/* without this, an object can rest on the old physics mesh
-	 * and not move to account for the physics mesh, even with 'nosleep' */ 
-	btSoftRigidDynamicsWorld* dw= GetPhysicsEnvironment()->GetDynamicsWorld();
-	btCollisionObjectArray &obarr= dw->getCollisionObjectArray();
-	btCollisionObject *ob;
-	btBroadphaseProxy* proxy;
 
-	for (int i= 0; i < obarr.size(); i++) {
-		ob= obarr[i];
-		if (ob->getCollisionShape() == newShape) {
-			proxy = ob->getBroadphaseHandle();
-			
-			if (proxy)
-				dw->getPairCache()->cleanProxyFromPairs(proxy,dw->getDispatcher());
-		}
+		btSoftBody *newSoftBody = GetSoftBody();
+		// set the user
+		newSoftBody->setUserPointer(this);
+		// add the new softbody
+		world->addSoftBody(newSoftBody);
 	}
-	
+
 	return true;
 }
 
@@ -1742,30 +1727,22 @@ PHY_IPhysicsController*	CcdPhysicsController::GetReplicaForSensors()
  * 2) from_gameobj - creates the phys mesh from the DerivedMesh where possible, else the RAS_MeshObject
  * 3) this - update the phys mesh from DerivedMesh or RAS_MeshObject
  *
- * Most of the logic behind this is in shapeInfo->UpdateMesh(...)
+ * Most of the logic behind this is in m_shapeInfo->UpdateMesh(...)
  */
 bool CcdPhysicsController::ReinstancePhysicsShape(KX_GameObject *from_gameobj, RAS_MeshObject *from_meshobj)
 {
-	CcdShapeConstructionInfo	*shapeInfo;
-
-	shapeInfo = this->GetShapeInfo();
-
-	if (shapeInfo->m_shapeType != PHY_SHAPE_MESH/* || spc->GetSoftBody()*/)
+	if (m_shapeInfo->m_shapeType != PHY_SHAPE_MESH)
 		return false;
 
-	this->DeleteControllerShape();
-
-	if (from_gameobj==NULL && from_meshobj==NULL)
-		from_gameobj = KX_GameObject::GetClientObject((KX_ClientObjectInfo*)this->GetNewClientInfo());
+	if (!from_gameobj && !from_meshobj)
+		from_gameobj = KX_GameObject::GetClientObject((KX_ClientObjectInfo*)GetNewClientInfo());
 
 	/* updates the arrays used for making the new bullet mesh */
-	shapeInfo->UpdateMesh(from_gameobj, from_meshobj);
+	m_shapeInfo->UpdateMesh(from_gameobj, from_meshobj);
 
 	/* create the new bullet mesh */
-	CcdConstructionInfo& cci = this->GetConstructionInfo();
-	btCollisionShape* bm= shapeInfo->CreateBulletShape(cci.m_margin, cci.m_bGimpact, !cci.m_bSoft);
+	GetPhysicsEnvironment()->UpdateCcdPhysicsControllerShape(m_shapeInfo);
 
-	this->ReplaceControllerShape(bm);
 	return true;
 }
 
@@ -2494,11 +2471,9 @@ bool CcdShapeConstructionInfo::UpdateMesh(class KX_GameObject *gameobj, class RA
 	}
 #endif
 
-	/* force recreation of the m_unscaledShape.
+	/* force recreation of the m_triangleIndexVertexArray.
 	 * If this has multiple users we cant delete */
-	if (m_unscaledShape) {
-		// don't free now so it can re-allocate under the same location and not break pointers.
-		// DeleteBulletShape(m_unscaledShape);
+	if (m_triangleIndexVertexArray) {
 		m_forceReInstance = true;
 	}
 
@@ -2582,74 +2557,60 @@ btCollisionShape* CcdShapeConstructionInfo::CreateBulletShape(btScalar margin, b
 		// 9 multiplications/additions and one function call for each triangle that passes the mid phase filtering
 		// One possible optimization is to use directly the btBvhTriangleMeshShape when the scale is 1,1,1
 		// and btScaledBvhTriangleMeshShape otherwise.
-		if (useGimpact)
-		{
-				btTriangleIndexVertexArray* indexVertexArrays = new btTriangleIndexVertexArray(
+		if (useGimpact) {
+			if (!m_triangleIndexVertexArray || m_forceReInstance) {
+				if (m_triangleIndexVertexArray)
+					delete m_triangleIndexVertexArray;
+
+				m_triangleIndexVertexArray = new btTriangleIndexVertexArray(
 						m_polygonIndexArray.size(),
-						&m_triFaceArray[0],
-						3*sizeof(int),
-						m_vertexArray.size()/3,
+						m_triFaceArray.data(),
+						3 * sizeof(int),
+						m_vertexArray.size() / 3,
 						&m_vertexArray[0],
-						3*sizeof(btScalar)
-				);
-				btGImpactMeshShape* gimpactShape =  new btGImpactMeshShape(indexVertexArrays);
-				gimpactShape->setMargin(margin);
-				gimpactShape->updateBound();
-				collisionShape = gimpactShape;
-				
-
-		} else
-		{
-			if (!m_unscaledShape || m_forceReInstance)
-			{
-			
-				btTriangleIndexVertexArray* indexVertexArrays = 0;
+						3 * sizeof(btScalar));
+				m_forceReInstance = false;
+			}
 
+			btGImpactMeshShape *gimpactShape = new btGImpactMeshShape(m_triangleIndexVertexArray);
+			gimpactShape->setMargin(margin);
+			gimpactShape->updateBound();
+			collisionShape = gimpactShape;
+		}
+		else {
+			if (!m_triangleIndexVertexArray || m_forceReInstance) {
 				///enable welding, only for the objects that need it (such as soft bodies)
-				if (0.f != m_weldingThreshold1)
-				{
-					btTriangleMesh* collisionMeshData = new btTriangleMesh(true,false);
+				if (0.0f != m_weldingThreshold1) {
+					btTriangleMesh *collisionMeshData = new btTriangleMesh(true, false);
 					collisionMeshData->m_weldingThreshold = m_weldingThreshold1;
-					bool removeDuplicateVertices=true;
+					bool removeDuplicateVertices = true;
 					// m_vertexArray not in multiple of 3 anymore, use m_triFaceArray
-					for (unsigned int i=0; i<m_triFaceArray.size(); i+=3) {
-						btScalar *bt = &m_vertexArray[3*m_triFaceArray[i]];
+					for (unsigned int i = 0; i < m_triFaceArray.size(); i += 3) {
+						btScalar *bt = &m_vertexArray[3 * m_triFaceArray[i]];
 						btVector3 v1(bt[0], bt[1], bt[2]);
-						bt = &m_vertexArray[3*m_triFaceArray[i+1]];
+						bt = &m_vertexArray[3 * m_triFaceArray[i + 1]];
 						btVector3 v2(bt[0], bt[1], bt[2]);
-						bt = &m_vertexArray[3*m_triFaceArray[i+2]];
+						bt = &m_vertexArray[3 * m_triFaceArray[i + 2]];
 						btVector3 v3(bt[0], bt[1], bt[2]);
 						collisionMeshData->addTriangle(v1, v2, v3, removeDuplicateVertices);
 					}
-					indexVertexArrays = collisionMeshData;
-
-				} else
-				{
-					indexVertexArrays = new btTriangleIndexVertexArray(
+					m_triangleIndexVertexArray = collisionMeshData;
+				}
+				else {
+					m_triangleIndexVertexArray = new btTriangleIndexVertexArray(
 							m_polygonIndexArray.size(),
-							&m_triFaceArray[0],
-							3*sizeof(int),
-							m_vertexArray.size()/3,
+							m_triFaceArray.data(),
+							3 * sizeof(int),
+							m_vertexArray.size() / 3,
 							&m_vertexArray[0],
-							3*sizeof(btScalar));
+							3 * sizeof(btScalar));
 				}
-				
-				// this shape will be shared and not deleted until shapeInfo is deleted
-				
-				// for UpdateMesh, reuse the last memory location so instancing wont crash.
-				if (m_unscaledShape) {
-					DeleteBulletShape(m_unscaledShape, false);
-					m_unscaledShape->~btBvhTriangleMeshShape();
-					m_unscaledShape = new(m_unscaledShape) btBvhTriangleMeshShape( indexVertexArrays, true, useBvh );
-				} else {
-					m_unscaledShape = new btBvhTriangleMeshShape( indexVertexArrays, true, useBvh );
-				}
-				m_forceReInstance= false;
-			} else if (useBvh && m_unscaledShape->getOptimizedBvh() == NULL) {
-				// the existing unscaledShape was not build with Bvh, do it now
-				m_unscaledShape->buildOptimizedBvh();
+
+				m_forceReInstance = false;
 			}
-			collisionShape = new btScaledBvhTriangleMeshShape(m_unscaledShape, btVector3(1.0f,1.0f,1.0f));
+
+			btBvhTriangleMeshShape *unscaledShape = new btBvhTriangleMeshShape(m_triangleIndexVertexArray, true, useBvh);
+			collisionShape = new btScaledBvhTriangleMeshShape(unscaledShape, btVector3(1.0f, 1.0f, 1.0f));
 			collisionShape->setMargin(margin);
 		}
 		break;
@@ -2691,10 +2652,9 @@ CcdShapeConstructionInfo::~CcdShapeConstructionInfo()
 		(*sit)->Release();
 	}
 	m_shapeArray.clear();
-	if (m_unscaledShape)
-	{
-		DeleteBulletShape(m_unscaledShape, true);
-	}
+
+	if (m_triangleIndexVertexArray)
+		delete m_triangleIndexVertexArray;
 	m_vertexArray.clear();
 	if (m_shapeType == PHY_SHAPE_MESH && m_meshObject != NULL) 
 	{

source/gameengine/Physics/Bullet/CcdPhysicsController.h

@@ -79,7 +79,7 @@ public:
 		m_userData(NULL),
 		m_refCount(1),
 		m_meshObject(NULL),
-		m_unscaledShape(NULL),
+		m_triangleIndexVertexArray(NULL),
 		m_forceReInstance(false),
 		m_weldingThreshold1(0.f),
 		m_shapeProxy(NULL)
@@ -110,10 +110,11 @@ public:
 
 	void AddShape(CcdShapeConstructionInfo* shapeInfo);
 
-	btTriangleMeshShape* GetMeshShape(void)
+	btStridingMeshInterface *GetMeshInterface()
 	{
-		return (m_unscaledShape);
+		return m_triangleIndexVertexArray;
 	}
+
 	CcdShapeConstructionInfo* GetChildShape(int i)
 	{
 		if (i < 0 || i >= (int)m_shapeArray.size())
@@ -195,8 +196,8 @@ protected:
 	int						m_refCount;		// this class is shared between replicas
 											// keep track of users so that we can release it 
 	RAS_MeshObject*	m_meshObject;			// Keep a pointer to the original mesh 
-	btBvhTriangleMeshShape* m_unscaledShape;// holds the shared unscale BVH mesh shape, 
-											// the actual shape is of type btScaledBvhTriangleMeshShape
+	// The list of vertexes and indexes for the triangle mesh, shared between Bullet shape.
+	btTriangleIndexVertexArray *m_triangleIndexVertexArray;
 	std::vector<CcdShapeConstructionInfo*> m_shapeArray;	// for compound shapes
 	bool	m_forceReInstance; //use gimpact for concave dynamic/moving collision detection
 	float	m_weldingThreshold1;	//welding closeby vertices together can improve softbody stability etc.
@@ -535,7 +536,15 @@ protected:
 
 		CcdPhysicsController (const CcdConstructionInfo& ci);
 
+		/**
+		* Delete the current Bullet shape used in the rigid body.
+		*/
 		bool DeleteControllerShape();
+
+		/**
+		* Delete the old Bullet shape and set the new Bullet shape : newShape
+		* \param newShape The new Bullet shape to set, if is NULL we create a new Bullet shape
+		*/
 		bool ReplaceControllerShape(btCollisionShape *newShape);
 
 		virtual ~CcdPhysicsController();

source/gameengine/Physics/Bullet/CcdPhysicsEnvironment.cpp

@@ -671,6 +671,19 @@ void CcdPhysicsEnvironment::RemoveCcdGraphicController(CcdGraphicController* ctr
 	}
 }
 
+void CcdPhysicsEnvironment::UpdateCcdPhysicsControllerShape(CcdShapeConstructionInfo *shapeInfo)
+{
+	for (std::set<CcdPhysicsController *>::iterator it = m_controllers.begin(); it != m_controllers.end(); ++it) {
+		CcdPhysicsController *ctrl = *it;
+
+		if (ctrl->GetShapeInfo() != shapeInfo)
+			continue;
+
+		ctrl->ReplaceControllerShape(NULL);
+		RefreshCcdPhysicsController(ctrl);
+	}
+}
+
 void	CcdPhysicsEnvironment::BeginFrame()
 {
 
@@ -1156,17 +1169,8 @@ static bool GetHitTriangle(btCollisionShape* shape, CcdShapeConstructionInfo* sh
 	int indexstride;
 	int numfaces;
 	PHY_ScalarType indicestype;
-	btStridingMeshInterface* meshInterface = NULL;
-	btTriangleMeshShape* triangleShape = shapeInfo->GetMeshShape();
+	btStridingMeshInterface* meshInterface = shapeInfo->GetMeshInterface();
 
-	if (triangleShape)
-		meshInterface = triangleShape->getMeshInterface();
-	else
-	{
-		// other possibility is gImpact
-		if (shape->getShapeType() == GIMPACT_SHAPE_PROXYTYPE)
-			meshInterface = (static_cast<btGImpactMeshShape*>(shape))->getMeshInterface();
-	}
 	if (!meshInterface)
 		return false;
 

source/gameengine/Physics/Bullet/CcdPhysicsEnvironment.h

@@ -54,6 +54,7 @@ class btOverlappingPairCache;
 class btIDebugDraw;
 class PHY_IVehicle;
 class CcdOverlapFilterCallBack;
+class CcdShapeConstructionInfo;
 
 /** CcdPhysicsEnvironment is an experimental mainloop for physics simulation using optional continuous collision detection.
  * Physics Environment takes care of stepping the simulation and is a container for physics entities.
@@ -229,6 +230,14 @@ protected:
 
 		void	RemoveCcdGraphicController(CcdGraphicController* ctrl);
 
+		/** 
+		 * Update all physics controllers shape which use the same shape construction info.
+		 * Call RecreateControllerShape on controllers which use the same shape
+		 * construction info that argument shapeInfo.
+		 * You need to call this function when the shape construction info changed.
+		 */
+		void	UpdateCcdPhysicsControllerShape(CcdShapeConstructionInfo *shapeInfo);
+
 		btBroadphaseInterface*	GetBroadphase();
 		btDbvtBroadphase*	GetCullingTree() { return m_cullingTree; }