Added btUniformScalingShape (including support for debug rendering etc)

This allows to re-use a convex shape, while each instance can re-scale it (with a uniform scalar factor)

src/BulletCollision/BroadphaseCollision/btBroadphaseProxy.h

@@ -38,6 +38,7 @@ IMPLICIT_CONVEX_SHAPES_START_HERE,
 	CONE_SHAPE_PROXYTYPE,
 	CONVEX_SHAPE_PROXYTYPE,
 	CYLINDER_SHAPE_PROXYTYPE,
+	UNIFORM_SCALING_SHAPE_PROXYTYPE,
 	MINKOWSKI_SUM_SHAPE_PROXYTYPE,
 	MINKOWSKI_DIFFERENCE_SHAPE_PROXYTYPE,
 //concave shapes

src/BulletCollision/CollisionShapes/btUniformScalingShape.cpp

@@ -0,0 +1,53 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2007 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "btUniformScalingShape.h"
+
+btUniformScalingShape::btUniformScalingShape(	btConvexShape* convexChildShape,btScalar uniformScalingFactor):
+m_childConvexShape(convexChildShape),
+m_uniformScalingFactor(uniformScalingFactor)
+{
+}
+	
+btUniformScalingShape::~btUniformScalingShape()
+{
+}
+	
+
+btVector3	btUniformScalingShape::localGetSupportingVertexWithoutMargin(const btVector3& vec)const
+{
+	btVector3 tmpVertex;
+	tmpVertex = m_childConvexShape->localGetSupportingVertexWithoutMargin(vec);
+	return tmpVertex*m_uniformScalingFactor;
+}
+
+void	btUniformScalingShape::batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const
+{
+	m_childConvexShape->batchedUnitVectorGetSupportingVertexWithoutMargin(vectors,supportVerticesOut,numVectors);
+	int i;
+	for (i=0;i<numVectors;i++)
+	{
+		supportVerticesOut[i] = supportVerticesOut[i] * m_uniformScalingFactor;
+	}
+}
+
+void	btUniformScalingShape::calculateLocalInertia(btScalar mass,btVector3& inertia)
+{
+
+	///this linear upscaling is not realistic, but we don't deal with large mass ratios...
+	btVector3 tmpInertia;
+	m_childConvexShape->calculateLocalInertia(mass,tmpInertia);
+	inertia = tmpInertia * m_uniformScalingFactor;
+}

src/BulletCollision/CollisionShapes/btUniformScalingShape.h

@@ -0,0 +1,64 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef BT_UNIFORM_SCALING_SHAPE_H
+#define BT_UNIFORM_SCALING_SHAPE_H
+
+#include "btConvexShape.h"
+#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h" // for the types
+
+class btUniformScalingShape : public btConvexShape
+{
+	btConvexShape*	m_childConvexShape;
+
+	btScalar	m_uniformScalingFactor;
+	
+	public:
+	
+	btUniformScalingShape(	btConvexShape* convexChildShape, btScalar uniformScalingFactor);
+	
+	virtual ~btUniformScalingShape();
+	
+	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;
+
+	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;
+
+	virtual void	calculateLocalInertia(btScalar mass,btVector3& inertia);
+
+	btScalar	getUniformScalingFactor() const
+	{
+		return m_uniformScalingFactor;
+	}
+
+	btConvexShape*	getChildShape() 
+	{
+		return m_childConvexShape;
+	}
+
+	const btConvexShape*	getChildShape() const
+	{
+		return m_childConvexShape;
+	}
+
+	virtual char*	getName()const 
+	{
+		return "UniformScalingShape";
+	}
+	
+	virtual int	getShapeType() const { return UNIFORM_SCALING_SHAPE_PROXYTYPE; }
+	
+};
+
+#endif //BT_UNIFORM_SCALING_SHAPE_H