fix some out-of-bounds error in the OpenCL rigid body pipeline

re-enable an OpenCL/gpu rigid body example (box-box stack)

examples/OpenCL/rigidbody/GpuRigidBodyDemo.h

@@ -0,0 +1,47 @@
+#ifndef GPU_RIGID_BODY_DEMO_H
+#define GPU_RIGID_BODY_DEMO_H
+
+
+#include "Bullet3Common/b3Vector3.h"
+#include "../CommonOpenCL/CommonOpenCLBase.h"
+
+
+class GpuRigidBodyDemo : public CommonOpenCLBase
+{
+protected:
+	class GLInstancingRenderer* m_instancingRenderer;
+	class GLPrimitiveRenderer*	m_primRenderer;
+	class CommonWindowInterface*	m_window;
+
+	struct GpuRigidBodyDemoInternalData*	m_data;
+
+public:
+	
+
+	GpuRigidBodyDemo(GUIHelperInterface* helper);
+	virtual ~GpuRigidBodyDemo();
+
+	virtual void	initPhysics();
+
+	virtual void	setupScene();
+
+	virtual void	destroyScene(){};
+
+	virtual void	exitPhysics();
+	
+	virtual void renderScene();
+	
+	
+	virtual void stepSimulation(float deltaTime);
+
+	//for picking
+	b3Vector3	getRayTo(int x,int y);
+	virtual bool	mouseMoveCallback(float x,float y);
+	virtual bool	mouseButtonCallback(int button, int state, float x, float y);
+	virtual bool	keyboardCallback(int key, int state);
+
+	unsigned char* loadImage(const char* fileName, int& width, int& height, int& n);
+};
+
+#endif //GPU_RIGID_BODY_DEMO_H
+