source: code/archive/animated_space_boundaries/src/external/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 BT_CYLINDER_MINKOWSKI_H
#define BT_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 //BT_CYLINDER_MINKOWSKI_H