some work on compound collision shapes (not finished yet)

Bullet/CollisionDispatch/CollisionDispatcher.cpp

@@ -21,6 +21,7 @@ subject to the following restrictions:
 #include "CollisionDispatch/ConvexConvexAlgorithm.h"
 #include "CollisionDispatch/EmptyCollisionAlgorithm.h"
 #include "CollisionDispatch/ConvexConcaveCollisionAlgorithm.h"
+#include "CollisionDispatch/CompoundCollisionAlgorithm.h"
 #include "CollisionShapes/CollisionShape.h"
 #include "CollisionDispatch/CollisionObject.h"
 #include <algorithm>
@@ -122,6 +123,17 @@ CollisionAlgorithm* CollisionDispatcher::InternalFindAlgorithm(BroadphaseProxy&
 		return new ConvexConcaveCollisionAlgorithm(ci,&proxy1,&proxy0);
 	}
 
+	if (body0->m_collisionShape->IsCompound())
+	{
+		return new CompoundCollisionAlgorithm(ci,&proxy0,&proxy1);
+	} else
+	{
+		if (body1->m_collisionShape->IsCompound())
+		{
+			return new CompoundCollisionAlgorithm(ci,&proxy1,&proxy0);
+		}
+	}
+
 	//failed to find an algorithm
 	return new EmptyAlgorithm(ci);
 	

Bullet/CollisionDispatch/CollisionWorld.cpp

@@ -20,6 +20,7 @@ subject to the following restrictions:
 #include "CollisionShapes/SphereShape.h" //for raycasting
 #include "CollisionShapes/TriangleMeshShape.h" //for raycasting
 #include "NarrowPhaseCollision/RaycastCallback.h"
+#include "CollisionShapes/CompoundShape.h"
 
 #include "NarrowPhaseCollision/SubSimplexConvexCast.h"
 #include "BroadphaseCollision/BroadphaseInterface.h"
@@ -139,58 +140,27 @@ void	CollisionWorld::RemoveCollisionObject(CollisionObject* collisionObject)
 		}
 }
 
-
+void	RayTestSingle(const SimdTransform& rayFromTrans,const SimdTransform& rayToTrans,
-
+					  CollisionObject* collisionObject,
-void	CollisionWorld::RayTest(const SimdVector3& rayFromWorld, const SimdVector3& rayToWorld, RayResultCallback& resultCallback)
+					  const CollisionShape* collisionShape,
+					  const SimdTransform& colObjWorldTransform,
+					  CollisionWorld::RayResultCallback& resultCallback)
 {
 	
-	
-	SimdTransform	rayFromTrans,rayToTrans;
-	rayFromTrans.setIdentity();
-	rayFromTrans.setOrigin(rayFromWorld);
-	rayToTrans.setIdentity();
-	
-	rayToTrans.setOrigin(rayToWorld);
-
-	//do culling based on aabb (rayFrom/rayTo)
-	SimdVector3 rayAabbMin = rayFromWorld;
-	SimdVector3 rayAabbMax = rayFromWorld;
-	rayAabbMin.setMin(rayToWorld);
-	rayAabbMax.setMax(rayToWorld);
-
 	SphereShape pointShape(0.0f);
 
-	/// brute force go over all objects. Once there is a broadphase, use that, or
+	if (collisionShape->IsConvex())
-	/// add a raycast against aabb first.
-	
-	std::vector<CollisionObject*>::iterator iter;
-	
-	for (iter=m_collisionObjects.begin();
-	!(iter==m_collisionObjects.end()); iter++)
-	{
-		
-		CollisionObject*	collisionObject= (*iter);
-
-		//RigidcollisionObject* collisionObject = ctrl->GetRigidcollisionObject();
-		SimdVector3 collisionObjectAabbMin,collisionObjectAabbMax;
-		collisionObject->m_collisionShape->GetAabb(collisionObject->m_worldTransform,collisionObjectAabbMin,collisionObjectAabbMax);
-
-		//check aabb overlap
-
-		if (TestAabbAgainstAabb2(rayAabbMin,rayAabbMax,collisionObjectAabbMin,collisionObjectAabbMax))
-		{
-			if (collisionObject->m_collisionShape->IsConvex())
 			{
 				ConvexCast::CastResult castResult;
 				castResult.m_fraction = 1.f;//??
 
-				ConvexShape* convexShape = (ConvexShape*) collisionObject->m_collisionShape;
+				ConvexShape* convexShape = (ConvexShape*) collisionShape;
 				VoronoiSimplexSolver	simplexSolver;
 				SubsimplexConvexCast convexCaster(&pointShape,convexShape,&simplexSolver);
 				//GjkConvexCast	convexCaster(&pointShape,convexShape,&simplexSolver);
 				//ContinuousConvexCollision convexCaster(&pointShape,convexShape,&simplexSolver,0);
 				
-				if (convexCaster.calcTimeOfImpact(rayFromTrans,rayToTrans,collisionObject->m_worldTransform,collisionObject->m_worldTransform,castResult))
+				if (convexCaster.calcTimeOfImpact(rayFromTrans,rayToTrans,colObjWorldTransform,colObjWorldTransform,castResult))
 				{
 					//add hit
 					if (castResult.m_normal.length2() > 0.0001f)
@@ -217,12 +187,12 @@ void	CollisionWorld::RayTest(const SimdVector3& rayFromWorld, const SimdVector3&
 			else
 			{
 				
-				if (collisionObject->m_collisionShape->IsConcave())
+				if (collisionShape->IsConcave())
 					{
 
-						TriangleMeshShape* triangleMesh = (TriangleMeshShape*)collisionObject->m_collisionShape;
+						TriangleMeshShape* triangleMesh = (TriangleMeshShape*)collisionShape;
 						
-						SimdTransform worldTocollisionObject = collisionObject->m_worldTransform.inverse();
+						SimdTransform worldTocollisionObject = colObjWorldTransform.inverse();
 
 						SimdVector3 rayFromLocal = worldTocollisionObject * rayFromTrans.getOrigin();
 						SimdVector3 rayToLocal = worldTocollisionObject * rayToTrans.getOrigin();
@@ -231,12 +201,12 @@ void	CollisionWorld::RayTest(const SimdVector3& rayFromWorld, const SimdVector3&
 
 						struct BridgeTriangleRaycastCallback : public TriangleRaycastCallback 
 						{
-							RayResultCallback* m_resultCallback;
+							CollisionWorld::RayResultCallback* m_resultCallback;
 							CollisionObject*	m_collisionObject;
 							TriangleMeshShape*	m_triangleMesh;
 
 							BridgeTriangleRaycastCallback( const SimdVector3& from,const SimdVector3& to,
-								RayResultCallback* resultCallback, CollisionObject* collisionObject,TriangleMeshShape*	triangleMesh):
+								CollisionWorld::RayResultCallback* resultCallback, CollisionObject* collisionObject,TriangleMeshShape*	triangleMesh):
 								TriangleRaycastCallback(from,to),
 									m_resultCallback(resultCallback),
 									m_collisionObject(collisionObject),
@@ -275,11 +245,76 @@ void	CollisionWorld::RayTest(const SimdVector3& rayFromWorld, const SimdVector3&
 
 						triangleMesh->ProcessAllTriangles(&rcb,rayAabbMinLocal,rayAabbMaxLocal);
 											
+					} else
+					{
+						//todo: use AABB tree or other BVH acceleration structure!
+						if (collisionShape->IsCompound())
+						{
+							const CompoundShape* compoundShape = static_cast<const CompoundShape*>(collisionShape);
+							int i=0;
+							for (i=0;i<compoundShape->GetNumChildShapes();i++)
+							{
+								SimdTransform childTrans = compoundShape->GetChildTransform(i);
+								const CollisionShape* childCollisionShape = compoundShape->GetChildShape(i);
+								SimdTransform childWorldTrans = colObjWorldTransform * childTrans;
+								RayTestSingle(rayFromTrans,rayToTrans,
+									collisionObject,
+									childCollisionShape,
+									childWorldTrans,
+									resultCallback);
+
 							}
 
 
 						}
 					}
 			}
+}
+
+void	CollisionWorld::RayTest(const SimdVector3& rayFromWorld, const SimdVector3& rayToWorld, RayResultCallback& resultCallback)
+{
+
+	
+	SimdTransform	rayFromTrans,rayToTrans;
+	rayFromTrans.setIdentity();
+	rayFromTrans.setOrigin(rayFromWorld);
+	rayToTrans.setIdentity();
+	
+	rayToTrans.setOrigin(rayToWorld);
+
+	//do culling based on aabb (rayFrom/rayTo)
+	SimdVector3 rayAabbMin = rayFromWorld;
+	SimdVector3 rayAabbMax = rayFromWorld;
+	rayAabbMin.setMin(rayToWorld);
+	rayAabbMax.setMax(rayToWorld);
+
+
+	/// brute force go over all objects. Once there is a broadphase, use that, or
+	/// add a raycast against aabb first.
+	
+	std::vector<CollisionObject*>::iterator iter;
+	
+	for (iter=m_collisionObjects.begin();
+	!(iter==m_collisionObjects.end()); iter++)
+	{
+		
+		CollisionObject*	collisionObject= (*iter);
+
+		//RigidcollisionObject* collisionObject = ctrl->GetRigidcollisionObject();
+		SimdVector3 collisionObjectAabbMin,collisionObjectAabbMax;
+		collisionObject->m_collisionShape->GetAabb(collisionObject->m_worldTransform,collisionObjectAabbMin,collisionObjectAabbMax);
+
+		//check aabb overlap
+
+		if (TestAabbAgainstAabb2(rayAabbMin,rayAabbMax,collisionObjectAabbMin,collisionObjectAabbMax))
+		{
+			RayTestSingle(rayFromTrans,rayToTrans,
+				collisionObject,
+					 collisionObject->m_collisionShape,
+					  collisionObject->m_worldTransform,
+					  resultCallback);
+			
+		}
+	}
 
 }

Bullet/CollisionDispatch/CompoundCollisionAlgorithm.cpp

@@ -14,19 +14,70 @@ subject to the following restrictions:
 */
 
 #include "CollisionDispatch/CompoundCollisionAlgorithm.h"
+#include "CollisionDispatch/CollisionObject.h"
+#include "CollisionShapes/CompoundShape.h"
 
 
 CompoundCollisionAlgorithm::CompoundCollisionAlgorithm( const CollisionAlgorithmConstructionInfo& ci,BroadphaseProxy* proxy0,BroadphaseProxy* proxy1)
+:m_dispatcher(ci.m_dispatcher),
+m_compoundProxy(*proxy0),
+m_otherProxy(*proxy1)
 {
+	CollisionObject* colObj = static_cast<CollisionObject*>(m_compoundProxy.m_clientObject);
+	assert (colObj->m_collisionShape->IsCompound());
+	
+	CompoundShape* compoundShape = static_cast<CompoundShape*>(colObj->m_collisionShape);
+	int numChildren = compoundShape->GetNumChildShapes();
+	m_childProxies.resize( numChildren );
+	int i;
+	for (i=0;i<numChildren;i++)
+	{
+		m_childProxies[i] = BroadphaseProxy(*proxy0);
 	}
 
+	m_childCollisionAlgorithms.resize(numChildren);
+	for (i=0;i<numChildren;i++)
+	{
+		CollisionShape* childShape = compoundShape->GetChildShape(i);
+		CollisionObject* colObj = static_cast<CollisionObject*>(m_childProxies[i].m_clientObject);
+		CollisionShape* orgShape = colObj->m_collisionShape;
+		colObj->m_collisionShape = childShape;
+		m_childCollisionAlgorithms[i] = m_dispatcher->FindAlgorithm(m_childProxies[i],m_otherProxy);
+		colObj->m_collisionShape =orgShape;
+	}
+}
+
+
 CompoundCollisionAlgorithm::~CompoundCollisionAlgorithm()
 {
+	int numChildren = m_childCollisionAlgorithms.size();
+	int i;
+	for (i=0;i<numChildren;i++)
+	{
+		delete m_childCollisionAlgorithms[i];
+	}
 }
 
-void CompoundCollisionAlgorithm::ProcessCollision (BroadphaseProxy* proxy0,BroadphaseProxy* proxy1,const DispatcherInfo& dispatchInfo)
+void CompoundCollisionAlgorithm::ProcessCollision (BroadphaseProxy* ,BroadphaseProxy* ,const DispatcherInfo& dispatchInfo)
 {
+	CollisionObject* colObj = static_cast<CollisionObject*>(m_compoundProxy.m_clientObject);
+	assert (colObj->m_collisionShape->IsCompound());
 	
+	CompoundShape* compoundShape = static_cast<CompoundShape*>(colObj->m_collisionShape);
+
+	int numChildren = m_childCollisionAlgorithms.size();
+	int i;
+	for (i=0;i<numChildren;i++)
+	{
+		//temporarily exchange parent CollisionShape with childShape, and recurse
+		CollisionShape* childShape = compoundShape->GetChildShape(i);
+		CollisionObject* colObj = static_cast<CollisionObject*>(m_childProxies[i].m_clientObject);
+		CollisionShape* orgShape = colObj->m_collisionShape;
+		colObj->m_collisionShape = childShape;
+		m_childCollisionAlgorithms[i]->ProcessCollision(&m_childProxies[i],&m_otherProxy,dispatchInfo);
+		//revert back
+		colObj->m_collisionShape =orgShape;
+	}
 }
 
 float	CompoundCollisionAlgorithm::CalculateTimeOfImpact(BroadphaseProxy* proxy0,BroadphaseProxy* proxy1,const DispatcherInfo& dispatchInfo)

Bullet/CollisionDispatch/CompoundCollisionAlgorithm.h

@@ -23,14 +23,19 @@ subject to the following restrictions:
 #include "NarrowPhaseCollision/PersistentManifold.h"
 class Dispatcher;
 #include "BroadphaseCollision/BroadphaseProxy.h"
-
+#include <vector>
 
 
 /// CompoundCollisionAlgorithm  supports collision between CompoundCollisionShapes and other collision shapes
 /// Place holder, not fully implemented yet
 class CompoundCollisionAlgorithm  : public CollisionAlgorithm
 {
+	BroadphaseProxy	m_compoundProxy;
+	BroadphaseProxy	m_otherProxy;
+	std::vector<BroadphaseProxy> m_childProxies;
+	std::vector<CollisionAlgorithm*> m_childCollisionAlgorithms;
 
+	Dispatcher*		m_dispatcher;
 	BroadphaseProxy m_compound;
 
 	BroadphaseProxy m_other;

Bullet/CollisionShapes/CompoundShape.cpp

@@ -20,6 +20,8 @@ subject to the following restrictions:
 
 
 CompoundShape::CompoundShape()
+:m_localAabbMin(1e30f,1e30f,1e30f),
+m_localAabbMax(-1e30f,-1e30f,-1e30f)
 {
 }
 
@@ -28,21 +30,66 @@ CompoundShape::~CompoundShape()
 {
 }
 
+void	CompoundShape::AddChildShape(const SimdTransform& localTransform,CollisionShape* shape)
+{
+	m_childTransforms.push_back(localTransform);
+	m_childShapes.push_back(shape);
+
+	//extend the local aabbMin/aabbMax
+	SimdVector3 localAabbMin,localAabbMax;
+	shape->GetAabb(localTransform,localAabbMin,localAabbMax);
+	for (int i=0;i<3;i++)
+	{
+		if (m_localAabbMin[i] > localAabbMin[i])
+		{
+			m_localAabbMin[i] = localAabbMin[i];
+		}
+		if (m_localAabbMax[i] < localAabbMax[i])
+		{
+			m_localAabbMax[i] = localAabbMax[i];
+		}
+
+	}
+}
+
+
 
 	///GetAabb's default implementation is brute force, expected derived classes to implement a fast dedicated version
-void CompoundShape::GetAabb(const SimdTransform& t,SimdVector3& aabbMin,SimdVector3& aabbMax) const
+void CompoundShape::GetAabb(const SimdTransform& trans,SimdVector3& aabbMin,SimdVector3& aabbMax) const
 {
-	SimdVector3 margin(GetMargin(),GetMargin(),GetMargin());
+	SimdVector3 localHalfExtents = 0.5f*(m_localAabbMax-m_localAabbMin);
+	SimdVector3 localCenter = 0.5f*(m_localAabbMax+m_localAabbMin);
 	
-	aabbMin = t.getOrigin() - margin;
+	SimdMatrix3x3 abs_b = trans.getBasis().absolute();  
 
-	aabbMax = t.getOrigin() + margin;
+	SimdPoint3 center = trans(localCenter);
 
+	SimdVector3 extent = SimdVector3(abs_b[0].dot(localHalfExtents),
+		   abs_b[1].dot(localHalfExtents),
+		  abs_b[2].dot(localHalfExtents));
+	extent += SimdVector3(GetMargin(),GetMargin(),GetMargin());
+
+	aabbMin = center - extent;
+	aabbMax = center + extent;
 }
 
 void	CompoundShape::CalculateLocalInertia(SimdScalar mass,SimdVector3& inertia)
 {
-	assert(0);
+	//approximation: take the inertia from the aabb for now
+	SimdTransform ident;
+	SimdVector3 aabbMin,aabbMax;
+	GetAabb(ident,aabbMin,aabbMax);
+	
+	SimdVector3 halfExtents = (aabbMax-aabbMin)*0.5f;
+	
+	SimdScalar lx=2.f*(halfExtents.x());
+	SimdScalar ly=2.f*(halfExtents.y());
+	SimdScalar lz=2.f*(halfExtents.z());
+
+	inertia[0] = mass/(12.0f) * (ly*ly + lz*lz);
+	inertia[1] = mass/(12.0f) * (lx*lx + lz*lz);
+	inertia[2] = mass/(12.0f) * (lx*lx + ly*ly);
+
 }
 
 	

Bullet/CollisionShapes/CompoundShape.h

@@ -28,14 +28,43 @@ subject to the following restrictions:
 
 /// CompoundShape allows to store multiple other CollisionShapes
 /// This allows for concave collision objects. This is more general then the Static Concave TriangleMeshShape.
-/// Place holder, not fully implemented yet
 class CompoundShape	: public CollisionShape
 {
+	std::vector<SimdTransform>		m_childTransforms;
+	std::vector<CollisionShape*>	m_childShapes;
+	SimdVector3						m_localAabbMin;
+	SimdVector3						m_localAabbMax;
+
+
 public:
 	CompoundShape();
 
 	virtual ~CompoundShape();
 
+	void	AddChildShape(const SimdTransform& localTransform,CollisionShape* shape);
+
+	int		GetNumChildShapes() const
+	{
+		return m_childShapes.size();
+	}
+
+	CollisionShape* GetChildShape(int index)
+	{
+		return m_childShapes[index];
+	}
+	const CollisionShape* GetChildShape(int index) const
+	{
+		return m_childShapes[index];
+	}
+
+	SimdTransform	GetChildTransform(int index)
+	{
+		return m_childTransforms[index];
+	}
+	const SimdTransform	GetChildTransform(int index) const
+	{
+		return m_childTransforms[index];
+	}
 
 	///GetAabb's default implementation is brute force, expected derived classes to implement a fast dedicated version
 	void GetAabb(const SimdTransform& t,SimdVector3& aabbMin,SimdVector3& aabbMax) const;

Demos/CcdPhysicsDemo/CcdPhysicsDemo.cpp

@@ -26,7 +26,7 @@ subject to the following restrictions:
 #include "CollisionShapes/SphereShape.h"
 #include "CollisionShapes/ConeShape.h"
 #include "CollisionShapes/StaticPlaneShape.h"
-
+#include "CollisionShapes/CompoundShape.h"
 #include "CollisionShapes/Simplex1to4Shape.h"
 #include "CollisionShapes/EmptyShape.h"
 
@@ -205,8 +205,13 @@ int main(int argc,char** argv)
 			shapeIndex[i] = 0;
 	}
 
+	CompoundShape* compoundShape = new CompoundShape();
+	//shapePtr[1] = compoundShape;
 
+	SimdTransform ident;
+	ident.setIdentity();
 
+	compoundShape->AddChildShape(ident,new BoxShape (SimdVector3(CUBE_HALF_EXTENTS,CUBE_HALF_EXTENTS,CUBE_HALF_EXTENTS)));
 
 	for (i=0;i<numObjects;i++)
 	{
@@ -498,8 +503,17 @@ void renderme()
 		char	extraDebug[125];
 		sprintf(extraDebug,"islId, Body=%i , %i",physObjects[i]->GetRigidBody()->m_islandTag1,physObjects[i]->GetRigidBody()->m_debugBodyId);
 		physObjects[i]->GetRigidBody()->GetCollisionShape()->SetExtraDebugInfo(extraDebug);
+
+		float vec[16];
+		SimdTransform ident;
+		ident.setIdentity();
+		ident.getOpenGLMatrix(vec);
+		glPushMatrix(); 
+	  glLoadMatrixf(vec);
+
 		GL_ShapeDrawer::DrawOpenGL(m,physObjects[i]->GetRigidBody()->GetCollisionShape(),wireColor,getDebugMode());
 
+		glPopMatrix(); 
 		///this block is just experimental code to show some internal issues with replacing shapes on the fly.
 		if (getDebugMode()!=0 && (i>0))
 		{

Demos/OpenGL/GL_ShapeDrawer.cpp

@@ -34,6 +34,7 @@ subject to the following restrictions:
 #include "CollisionShapes/ConeShape.h"
 #include "CollisionShapes/CylinderShape.h"
 #include "CollisionShapes/Simplex1to4Shape.h"
+#include "CollisionShapes/CompoundShape.h"
 
 #include "CollisionShapes/ConvexTriangleMeshShape.h"
 
@@ -105,9 +106,26 @@ public:
 
 void GL_ShapeDrawer::DrawOpenGL(float* m, const CollisionShape* shape, const SimdVector3& color,int	debugMode)
 {
-	glPushMatrix(); 
-    glLoadMatrixf(m);
 
+	
+	glPushMatrix(); 
+    glMultMatrixf(m);
+
+	if (shape->GetShapeType() == COMPOUND_SHAPE_PROXYTYPE)
+	{
+		const CompoundShape* compoundShape = static_cast<const CompoundShape*>(shape);
+		for (int i=0;i<compoundShape->GetNumChildShapes();i++)
+		{
+			SimdTransform childTrans = compoundShape->GetChildTransform(i);
+			const CollisionShape* colShape = compoundShape->GetChildShape(i);
+			float childMat[16];
+			childTrans.getOpenGLMatrix(childMat);
+			DrawOpenGL(childMat,colShape,color,debugMode);
+		}
+
+		return;
+	} else
+	{
 		//DrawCoordSystem();
 	    
 		glPushMatrix();
@@ -322,8 +340,8 @@ void GL_ShapeDrawer::DrawOpenGL(float* m, const CollisionShape* shape, const Sim
 			BMF_DrawString(BMF_GetFont(BMF_kHelvetica10),shape->GetExtraDebugInfo());
 		}
 		glEnable(GL_DEPTH_BUFFER_BIT);
-    
 		glPopMatrix();
+	}
     glPopMatrix();
 	
 }