BGE patch: allow Bullet mesh shape sharing for objects copied with ALT-D.

source/gameengine/Ketsji/KX_ConvertPhysicsObjects.cpp

@@ -767,7 +767,17 @@ void	KX_ConvertBulletObject(	class	KX_GameObject* gameobj,
 		{
 			if (!ci.m_mass)
 			{				
-				shapeInfo->SetMesh(meshobj, false);
+				// mesh shapes can be shared, check first if we already have a shape on that mesh
+				class CcdShapeConstructionInfo *sharedShapeInfo = CcdShapeConstructionInfo::FindMesh(meshobj, false);
+				if (sharedShapeInfo != NULL) 
+				{
+					delete shapeInfo;
+					shapeInfo = sharedShapeInfo;
+					shapeInfo->AddRef();
+				} else
+				{
+					shapeInfo->SetMesh(meshobj, false);
+				}
 				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

@@ -902,9 +902,25 @@ void	DefaultMotionState::calculateWorldTransformations()
 }
 
 // Shape constructor
+std::map<RAS_MeshObject*, CcdShapeConstructionInfo*> CcdShapeConstructionInfo::m_meshShapeMap;
+
+CcdShapeConstructionInfo* CcdShapeConstructionInfo::FindMesh(RAS_MeshObject* mesh, bool polytope)
+{
+	if (polytope)
+		// not yet supported
+		return NULL;
+
+	std::map<RAS_MeshObject*,CcdShapeConstructionInfo*>::const_iterator mit = m_meshShapeMap.find(mesh);
+	if (mit != m_meshShapeMap.end())
+		return mit->second;
+	return NULL;
+}
+
 bool CcdShapeConstructionInfo::SetMesh(RAS_MeshObject* meshobj, bool polytope)
 {
 	// assume no shape information
+	// no support for dynamic change of shape yet
+	assert(m_meshObject == NULL);
 	m_shapeType = PHY_SHAPE_NONE;
 	m_vertexArray.clear();
 	m_polygonIndexArray.clear();
@@ -1006,6 +1022,11 @@ bool CcdShapeConstructionInfo::SetMesh(RAS_MeshObject* meshobj, bool polytope)
 		return false;
 	}
 	m_meshObject = meshobj;
+	if (!polytope)
+	{
+		// triangle shape can be shared, store the mesh object in the map
+		m_meshShapeMap.insert(std::pair<RAS_MeshObject*,CcdShapeConstructionInfo*>(meshobj,this));
+	}
 	return true;
 }
 
@@ -1066,16 +1087,18 @@ btCollisionShape* CcdShapeConstructionInfo::CreateBulletShape()
 		break;
 
 	case PHY_SHAPE_COMPOUND:
-		if (m_nextShape)
+		if (m_shapeArray.size() > 0)
 		{
 			compoundShape = new btCompoundShape();
-			for (nextShapeInfo=m_nextShape; nextShapeInfo; nextShapeInfo = nextShapeInfo->m_nextShape)
+			for (std::vector<CcdShapeConstructionInfo*>::iterator sit = m_shapeArray.begin();
+				 sit != m_shapeArray.end();
+				 sit++)
 			{
-				collisionShape = nextShapeInfo->CreateBulletShape();
+				collisionShape = (*sit)->CreateBulletShape();
 				if (collisionShape)
 				{
-					collisionShape->setLocalScaling(nextShapeInfo->m_childScale);
-					compoundShape->addChildShape(nextShapeInfo->m_childTrans, collisionShape);
+					collisionShape->setLocalScaling((*sit)->m_childScale);
+					compoundShape->addChildShape((*sit)->m_childTrans, collisionShape);
 				}
 			}
 			collisionShape = compoundShape;
@@ -1086,28 +1109,31 @@ btCollisionShape* CcdShapeConstructionInfo::CreateBulletShape()
 
 void CcdShapeConstructionInfo::AddShape(CcdShapeConstructionInfo* shapeInfo)
 {
-	CcdShapeConstructionInfo* nextShape = this;
-	while (nextShape->m_nextShape != NULL)
-		nextShape = nextShape->m_nextShape;
-	nextShape->m_nextShape = shapeInfo;
+	m_shapeArray.push_back(shapeInfo);
 }
 
 CcdShapeConstructionInfo::~CcdShapeConstructionInfo()
 {
-	CcdShapeConstructionInfo* childShape = m_nextShape;
-
-	while (childShape)
+	for (std::vector<CcdShapeConstructionInfo*>::iterator sit = m_shapeArray.begin();
+		 sit != m_shapeArray.end();
+		 sit++)
 	{
-		CcdShapeConstructionInfo* nextShape = childShape->m_nextShape;
-		childShape->m_nextShape = NULL;
-		childShape->Release();
-		childShape = nextShape;
+		(*sit)->Release();
 	}
+	m_shapeArray.clear();
 	if (m_unscaledShape)
 	{
 		DeleteBulletShape(m_unscaledShape);
 	}
 	m_vertexArray.clear();
+	if (m_shapeType == PHY_SHAPE_MESH && m_meshObject != NULL) 
+	{
+		std::map<RAS_MeshObject*,CcdShapeConstructionInfo*>::iterator mit = m_meshShapeMap.find(m_meshObject);
+		if (mit != m_meshShapeMap.end() && mit->second == this)
+		{
+			m_meshShapeMap.erase(mit);
+		}
+	}
 }
 
 

source/gameengine/Physics/Bullet/CcdPhysicsController.h

@@ -18,6 +18,7 @@ subject to the following restrictions:
 #define BULLET2_PHYSICSCONTROLLER_H
 
 #include <vector>
+#include <map>
 
 #include "PHY_IPhysicsController.h"
 
@@ -42,15 +43,17 @@ class btCollisionShape;
 class CcdShapeConstructionInfo
 {
 public:
+	static CcdShapeConstructionInfo* FindMesh(RAS_MeshObject* mesh, bool polytope);
+
 	CcdShapeConstructionInfo() :
 		m_shapeType(PHY_SHAPE_NONE),
 		m_radius(1.0),
 		m_height(1.0),
 		m_halfExtend(0.f,0.f,0.f),
 		m_childScale(1.0f,1.0f,1.0f),
-		m_nextShape(NULL),
-		m_unscaledShape(NULL),
-		m_refCount(1)
+		m_refCount(1),
+		m_meshObject(NULL),
+		m_unscaledShape(NULL)
 	{
 		m_childTrans.setIdentity();
 	}
@@ -77,22 +80,19 @@ public:
 	{
 		return m_unscaledShape;
 	}
-	CcdShapeConstructionInfo* GetNextShape()
-	{
-		return m_nextShape;
-	}
 	CcdShapeConstructionInfo* GetChildShape(int i)
 	{
-		CcdShapeConstructionInfo* shape = m_nextShape;
-		while (i > 0 && shape != NULL)
-		{
-			shape = shape->m_nextShape;
-			i--;
-		}
-		return shape;
+		if (i < 0 || i >= m_shapeArray.size())
+			return NULL;
+
+		return m_shapeArray.at(i);
 	}
 
 	bool SetMesh(RAS_MeshObject* mesh, bool polytope);
+	RAS_MeshObject* GetMesh(void)
+	{
+		return m_meshObject;
+	}
 
 	btCollisionShape* CreateBulletShape();
 
@@ -109,14 +109,15 @@ public:
 	std::vector<int>		m_polygonIndexArray;	// Contains the array of polygon index in the 
 													// original mesh that correspond to shape triangles.
 													// only set for concave mesh shape.
-	const RAS_MeshObject*	m_meshObject;	// Keep a pointer to the original mesh 
 
 protected:
-	CcdShapeConstructionInfo* m_nextShape;	// for compound shape
-	btBvhTriangleMeshShape* m_unscaledShape;// holds the shared unscale BVH mesh shape, 
-											// the actual shape is of type btScaledBvhTriangleMeshShape
+	static std::map<RAS_MeshObject*, CcdShapeConstructionInfo*> m_meshShapeMap;
 	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
+	std::vector<CcdShapeConstructionInfo*> m_shapeArray;	// for compound shapes
 };
 
 struct CcdConstructionInfo

source/gameengine/Physics/Bullet/CcdPhysicsEnvironment.cpp

@@ -865,7 +865,7 @@ PHY_IPhysicsController* CcdPhysicsEnvironment::rayTest(PHY_IRayCastFilterCallbac
 				if (shape == rayCallback.m_hitTriangleShape && 
 					rayCallback.m_hitTriangleIndex < shapeInfo->m_polygonIndexArray.size())
 				{
-					result.m_meshObject = shapeInfo->m_meshObject;
+					result.m_meshObject = shapeInfo->GetMesh();
 					result.m_polygon = shapeInfo->m_polygonIndexArray.at(rayCallback.m_hitTriangleIndex);
 
 					// Bullet returns the normal from "outside".