gremlin/libs/bullet/BulletCollision/CollisionShapes/btCylinderShape.h

/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2009 Erwin Coumans  http://bulletphysics.org

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 CYLINDER_MINKOWSKI_H
#define CYLINDER_MINKOWSKI_H

#include "btBoxShape.h"
#include "BulletCollision/BroadphaseCollision/btBroadphaseProxy.h" // for the types
#include "LinearMath/btVector3.h"

/// The btCylinderShape class implements a cylinder shape primitive, centered around the origin. Its central axis aligned with the Y axis. btCylinderShapeX is aligned with the X axis and btCylinderShapeZ around the Z axis.
class btCylinderShape : public btConvexInternalShape

{

protected:

	int	m_upAxis;

public:

	btVector3 getHalfExtentsWithMargin() const
	{
		btVector3 halfExtents = getHalfExtentsWithoutMargin();
		btVector3 margin(getMargin(),getMargin(),getMargin());
		halfExtents += margin;
		return halfExtents;
	}
	
	const btVector3& getHalfExtentsWithoutMargin() const
	{
		return m_implicitShapeDimensions;//changed in Bullet 2.63: assume the scaling and margin are included
	}

	btCylinderShape (const btVector3& halfExtents);
	
	void getAabb(const btTransform& t,btVector3& aabbMin,btVector3& aabbMax) const;

	virtual void	calculateLocalInertia(btScalar mass,btVector3& inertia) const;

	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;

	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;

	virtual void setMargin(btScalar collisionMargin)
	{
		//correct the m_implicitShapeDimensions for the margin
		btVector3 oldMargin(getMargin(),getMargin(),getMargin());
		btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions+oldMargin;
		
		btConvexInternalShape::setMargin(collisionMargin);
		btVector3 newMargin(getMargin(),getMargin(),getMargin());
		m_implicitShapeDimensions = implicitShapeDimensionsWithMargin - newMargin;

	}

	virtual btVector3	localGetSupportingVertex(const btVector3& vec) const
	{

		btVector3 supVertex;
		supVertex = localGetSupportingVertexWithoutMargin(vec);
		
		if ( getMargin()!=btScalar(0.) )
		{
			btVector3 vecnorm = vec;
			if (vecnorm .length2() < (SIMD_EPSILON*SIMD_EPSILON))
			{
				vecnorm.setValue(btScalar(-1.),btScalar(-1.),btScalar(-1.));
			} 
			vecnorm.normalize();
			supVertex+= getMargin() * vecnorm;
		}
		return supVertex;
	}


	//use box inertia
	//	virtual void	calculateLocalInertia(btScalar mass,btVector3& inertia) const;


	int	getUpAxis() const
	{
		return m_upAxis;
	}

	virtual btScalar getRadius() const
	{
		return getHalfExtentsWithMargin().getX();
	}

	virtual void	setLocalScaling(const btVector3& scaling)
	{
		btVector3 oldMargin(getMargin(),getMargin(),getMargin());
		btVector3 implicitShapeDimensionsWithMargin = m_implicitShapeDimensions+oldMargin;
		btVector3 unScaledImplicitShapeDimensionsWithMargin = implicitShapeDimensionsWithMargin / m_localScaling;

		btConvexInternalShape::setLocalScaling(scaling);

		m_implicitShapeDimensions = (unScaledImplicitShapeDimensionsWithMargin * m_localScaling) - oldMargin;

	}

	//debugging
	virtual const char*	getName()const
	{
		return "CylinderY";
	}

	virtual	int	calculateSerializeBufferSize() const;

	///fills the dataBuffer and returns the struct name (and 0 on failure)
	virtual	const char*	serialize(void* dataBuffer, btSerializer* serializer) const;

};

class btCylinderShapeX : public btCylinderShape
{
public:
	btCylinderShapeX (const btVector3& halfExtents);

	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;
	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;
	
		//debugging
	virtual const char*	getName()const
	{
		return "CylinderX";
	}

	virtual btScalar getRadius() const
	{
		return getHalfExtentsWithMargin().getY();
	}

};

class btCylinderShapeZ : public btCylinderShape
{
public:
	btCylinderShapeZ (const btVector3& halfExtents);

	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;
	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;

		//debugging
	virtual const char*	getName()const
	{
		return "CylinderZ";
	}

	virtual btScalar getRadius() const
	{
		return getHalfExtentsWithMargin().getX();
	}

};

///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
struct	btCylinderShapeData
{
	btConvexInternalShapeData	m_convexInternalShapeData;

	int	m_upAxis;

	char	m_padding[4];
};

SIMD_FORCE_INLINE	int	btCylinderShape::calculateSerializeBufferSize() const
{
	return sizeof(btCylinderShapeData);
}

	///fills the dataBuffer and returns the struct name (and 0 on failure)
SIMD_FORCE_INLINE	const char*	btCylinderShape::serialize(void* dataBuffer, btSerializer* serializer) const
{
	btCylinderShapeData* shapeData = (btCylinderShapeData*) dataBuffer;
	
	btConvexInternalShape::serialize(&shapeData->m_convexInternalShapeData,serializer);

	shapeData->m_upAxis = m_upAxis;
	
	return "btCylinderShapeData";
}



#endif //CYLINDER_MINKOWSKI_H