+ disable perturbation for btConvexPlaneCollisionAlgorithm, it introduces artifacts (additional points cause spheres/cylinders and other curved objects to move)

+ applied patch to mix double/single precision meshes independent from double/single precision Bullet build
Thanks to Ole for the patch, http://code.google.com/p/bullet/issues/detail?id=213
+ re-enable warming starting in constraint solver, it was disabled by accident
+ fix btConvexHullShape constructor, so accept vertices with non-16-byte striding
Thanks Shawn Baird for report and fix: http://code.google.com/p/bullet/issues/detail?id=204

src/BulletCollision/CollisionDispatch/btConvexPlaneCollisionAlgorithm.h

@@ -60,8 +60,8 @@ public:
 		int m_minimumPointsPerturbationThreshold;
 			
 		CreateFunc() 
-			: m_numPerturbationIterations(3),
+			: m_numPerturbationIterations(1),
-			m_minimumPointsPerturbationThreshold(3)
+			m_minimumPointsPerturbationThreshold(1)
 		{
 		}
 		

src/BulletCollision/CollisionShapes/btConvexHullShape.cpp

@@ -24,12 +24,13 @@ btConvexHullShape ::btConvexHullShape (const btScalar* points,int numPoints,int
 	m_shapeType = CONVEX_HULL_SHAPE_PROXYTYPE;
 	m_unscaledPoints.resize(numPoints);
 
-	unsigned char* pointsBaseAddress = (unsigned char*)points;
+	unsigned char* pointsAddress = (unsigned char*)points;
 
 	for (int i=0;i<numPoints;i++)
 	{
-		btVector3* point = (btVector3*)(pointsBaseAddress + i*stride);
+		btScalar* point = (btScalar*)pointsAddress;
-		m_unscaledPoints[i] = point[0];
+		m_unscaledPoints[i] = btVector3(point[0], point[1], point[2]);
+		pointsAddress += stride;
 	}
 
 	recalcLocalAabb();

src/BulletCollision/CollisionShapes/btStridingMeshInterface.cpp

@@ -35,7 +35,6 @@ void	btStridingMeshInterface::InternalProcessAllTriangles(btInternalTriangleInde
    int stride,numverts,numtriangles;
    int gfxindex;
    btVector3 triangle[3];
-	btScalar* graphicsbase;
 
    btVector3 meshScaling = getScaling();
 
@@ -45,6 +44,19 @@ void	btStridingMeshInterface::InternalProcessAllTriangles(btInternalTriangleInde
       getLockedReadOnlyVertexIndexBase(&vertexbase,numverts,type,stride,&indexbase,indexstride,numtriangles,gfxindextype,part);
       numtotalphysicsverts+=numtriangles*3; //upper bound
 
+///unlike that developers want to pass in double-precision meshes in single-precision Bullet build
+///so disable this feature by default
+///see patch http://code.google.com/p/bullet/issues/detail?id=213
+
+#ifdef BT_USE_DOUBLE_PRECISION
+      switch (type)
+      {
+         case PHY_FLOAT:
+#endif
+		 {
+
+            float* graphicsbase;
+            
             switch (gfxindextype)
             {
                case PHY_INTEGER:
@@ -52,11 +64,11 @@ void	btStridingMeshInterface::InternalProcessAllTriangles(btInternalTriangleInde
                   for (gfxindex=0;gfxindex<numtriangles;gfxindex++)
                   {
                      unsigned int* tri_indices= (unsigned int*)(indexbase+gfxindex*indexstride);
-					graphicsbase = (btScalar*)(vertexbase+tri_indices[0]*stride);
+                     graphicsbase = (float*)(vertexbase+tri_indices[0]*stride);
                      triangle[0].setValue(graphicsbase[0]*meshScaling.getX(),graphicsbase[1]*meshScaling.getY(),graphicsbase[2]*meshScaling.getZ());
-					graphicsbase = (btScalar*)(vertexbase+tri_indices[1]*stride);
+                     graphicsbase = (float*)(vertexbase+tri_indices[1]*stride);
                      triangle[1].setValue(graphicsbase[0]*meshScaling.getX(),graphicsbase[1]*meshScaling.getY(),	graphicsbase[2]*meshScaling.getZ());
-					graphicsbase = (btScalar*)(vertexbase+tri_indices[2]*stride);
+                     graphicsbase = (float*)(vertexbase+tri_indices[2]*stride);
                      triangle[2].setValue(graphicsbase[0]*meshScaling.getX(),graphicsbase[1]*meshScaling.getY(),	graphicsbase[2]*meshScaling.getZ());
                      callback->internalProcessTriangleIndex(triangle,part,gfxindex);
                   }
@@ -67,11 +79,11 @@ void	btStridingMeshInterface::InternalProcessAllTriangles(btInternalTriangleInde
                   for (gfxindex=0;gfxindex<numtriangles;gfxindex++)
                   {
                      unsigned short int* tri_indices= (unsigned short int*)(indexbase+gfxindex*indexstride);
-					graphicsbase = (btScalar*)(vertexbase+tri_indices[0]*stride);
+                     graphicsbase = (float*)(vertexbase+tri_indices[0]*stride);
                      triangle[0].setValue(graphicsbase[0]*meshScaling.getX(),graphicsbase[1]*meshScaling.getY(),graphicsbase[2]*meshScaling.getZ());
-					graphicsbase = (btScalar*)(vertexbase+tri_indices[1]*stride);
+                     graphicsbase = (float*)(vertexbase+tri_indices[1]*stride);
                      triangle[1].setValue(graphicsbase[0]*meshScaling.getX(),graphicsbase[1]*meshScaling.getY(),	graphicsbase[2]*meshScaling.getZ());
-					graphicsbase = (btScalar*)(vertexbase+tri_indices[2]*stride);
+                     graphicsbase = (float*)(vertexbase+tri_indices[2]*stride);
                      triangle[2].setValue(graphicsbase[0]*meshScaling.getX(),graphicsbase[1]*meshScaling.getY(),	graphicsbase[2]*meshScaling.getZ());
                      callback->internalProcessTriangleIndex(triangle,part,gfxindex);
                   }
@@ -80,6 +92,55 @@ void	btStridingMeshInterface::InternalProcessAllTriangles(btInternalTriangleInde
                default:
                   btAssert((gfxindextype == PHY_INTEGER) || (gfxindextype == PHY_SHORT));
             }
+            break;
+         }
+
+#ifdef BT_USE_DOUBLE_PRECISION
+         case PHY_DOUBLE:
+         {
+            double* graphicsbase;
+
+            switch (gfxindextype)
+            {
+               case PHY_INTEGER:
+               {
+                  for (gfxindex=0;gfxindex<numtriangles;gfxindex++)
+                  {
+                     unsigned int* tri_indices= (unsigned int*)(indexbase+gfxindex*indexstride);
+                     graphicsbase = (double*)(vertexbase+tri_indices[0]*stride);
+                     triangle[0].setValue((btScalar)graphicsbase[0]*meshScaling.getX(),(btScalar)graphicsbase[1]*meshScaling.getY(),(btScalar)graphicsbase[2]*meshScaling.getZ());
+                     graphicsbase = (double*)(vertexbase+tri_indices[1]*stride);
+                     triangle[1].setValue((btScalar)graphicsbase[0]*meshScaling.getX(),(btScalar)graphicsbase[1]*meshScaling.getY(),  (btScalar)graphicsbase[2]*meshScaling.getZ());
+                     graphicsbase = (double*)(vertexbase+tri_indices[2]*stride);
+                     triangle[2].setValue((btScalar)graphicsbase[0]*meshScaling.getX(),(btScalar)graphicsbase[1]*meshScaling.getY(),  (btScalar)graphicsbase[2]*meshScaling.getZ());
+                     callback->internalProcessTriangleIndex(triangle,part,gfxindex);
+                  }
+                  break;
+               }
+               case PHY_SHORT:
+               {
+                  for (gfxindex=0;gfxindex<numtriangles;gfxindex++)
+                  {
+                     unsigned short int* tri_indices= (unsigned short int*)(indexbase+gfxindex*indexstride);
+                     graphicsbase = (double*)(vertexbase+tri_indices[0]*stride);
+                     triangle[0].setValue((btScalar)graphicsbase[0]*meshScaling.getX(),(btScalar)graphicsbase[1]*meshScaling.getY(),(btScalar)graphicsbase[2]*meshScaling.getZ());
+                     graphicsbase = (double*)(vertexbase+tri_indices[1]*stride);
+                     triangle[1].setValue((btScalar)graphicsbase[0]*meshScaling.getX(),(btScalar)graphicsbase[1]*meshScaling.getY(),  (btScalar)graphicsbase[2]*meshScaling.getZ());
+                     graphicsbase = (double*)(vertexbase+tri_indices[2]*stride);
+                     triangle[2].setValue((btScalar)graphicsbase[0]*meshScaling.getX(),(btScalar)graphicsbase[1]*meshScaling.getY(),  (btScalar)graphicsbase[2]*meshScaling.getZ());
+                     callback->internalProcessTriangleIndex(triangle,part,gfxindex);
+                  }
+                  break;
+               }
+               default:
+                  btAssert((gfxindextype == PHY_INTEGER) || (gfxindextype == PHY_SHORT));
+            }
+            break;
+         }
+         default:
+            btAssert((type == PHY_FLOAT) || (type == PHY_DOUBLE));
+      }
+#endif //BT_USE_DOUBLE_PRECISION
 
       unLockReadOnlyVertexBase(part);
    }

src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.cpp

@@ -44,11 +44,9 @@ void	btTriangleIndexVertexArray::getLockedVertexIndexBase(unsigned char **vertex
 
 	numverts = mesh.m_numVertices;
 	(*vertexbase) = (unsigned char *) mesh.m_vertexBase;
-	#ifdef BT_USE_DOUBLE_PRECISION
+
-	type = PHY_DOUBLE;
+   type = mesh.m_vertexType;
-	#else
+
-	type = PHY_FLOAT;
-	#endif
 	vertexStride = mesh.m_vertexStride;
 
 	numfaces = mesh.m_numTriangles;
@@ -64,11 +62,9 @@ void	btTriangleIndexVertexArray::getLockedReadOnlyVertexIndexBase(const unsigned
 
 	numverts = mesh.m_numVertices;
 	(*vertexbase) = (const unsigned char *)mesh.m_vertexBase;
-	#ifdef BT_USE_DOUBLE_PRECISION
+
-	type = PHY_DOUBLE;
+   type = mesh.m_vertexType;
-	#else
+   
-	type = PHY_FLOAT;
-	#endif
 	vertexStride = mesh.m_vertexStride;
 
 	numfaces = mesh.m_numTriangles;

src/BulletCollision/CollisionShapes/btTriangleIndexVertexArray.h

@@ -33,10 +33,25 @@ ATTRIBUTE_ALIGNED16( struct)	btIndexedMesh
    int                     m_numVertices;
    const unsigned char *   m_vertexBase;
    int                     m_vertexStride;
+
    // The index type is set when adding an indexed mesh to the
    // btTriangleIndexVertexArray, do not set it manually
    PHY_ScalarType m_indexType;
-	int			pad;
+
+   // The vertex type has a default type similar to Bullet's precision mode (float or double)
+   // but can be set manually if you for example run Bullet with double precision but have
+   // mesh data in single precision..
+   PHY_ScalarType m_vertexType;
+
+
+   btIndexedMesh()
+      {
+#ifdef BT_USE_DOUBLE_PRECISION
+      m_vertexType = PHY_DOUBLE;
+#else // BT_USE_DOUBLE_PRECISION
+      m_vertexType = PHY_FLOAT;
+#endif // BT_USE_DOUBLE_PRECISION
+      }
 }
 ;
 

src/BulletDynamics/ConstraintSolver/btContactSolverInfo.h

@@ -77,7 +77,7 @@ struct btContactSolverInfo : public btContactSolverInfoData
 		m_splitImpulsePenetrationThreshold = -0.02f;
 		m_linearSlop = btScalar(0.0);
 		m_warmstartingFactor=btScalar(0.85);
-		m_solverMode = SOLVER_USE_WARMSTARTING | SOLVER_SIMD ;//SOLVER_RANDMIZE_ORDER
+		m_solverMode = SOLVER_USE_WARMSTARTING | SOLVER_SIMD;// | SOLVER_RANDMIZE_ORDER;
 		m_restingContactRestitutionThreshold = 2;//resting contact lifetime threshold to disable restitution
 	}
 };

src/BulletDynamics/ConstraintSolver/btSequentialImpulseConstraintSolver.cpp

@@ -490,7 +490,7 @@ void	btSequentialImpulseConstraintSolver::convertContact(btPersistentManifold* m
 
 
 				///warm starting (or zero if disabled)
-				if (0)//infoGlobal.m_solverMode & SOLVER_USE_WARMSTARTING)
+				if (infoGlobal.m_solverMode & SOLVER_USE_WARMSTARTING)
 				{
 					solverConstraint.m_appliedImpulse = cp.m_appliedImpulse * infoGlobal.m_warmstartingFactor;
 					if (rb0)