source: code/releases/release2012/src/external/bullet/BulletCollision/CollisionShapes/btStridingMeshInterface.h @ 12412

/*
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_STRIDING_MESHINTERFACE_H
#define BT_STRIDING_MESHINTERFACE_H

#include "LinearMath/btVector3.h"
#include "btTriangleCallback.h"
#include "btConcaveShape.h"





///     The btStridingMeshInterface is the interface class for high performance generic access to triangle meshes, used in combination with btBvhTriangleMeshShape and some other collision shapes.
/// Using index striding of 3*sizeof(integer) it can use triangle arrays, using index striding of 1*sizeof(integer) it can handle triangle strips.
/// It allows for sharing graphics and collision meshes. Also it provides locking/unlocking of graphics meshes that are in gpu memory.
class  btStridingMeshInterface
{
        protected:
        
                btVector3 m_scaling;

        public:
                btStridingMeshInterface() :m_scaling(btScalar(1.),btScalar(1.),btScalar(1.))
                {

                }

                virtual ~btStridingMeshInterface();



                virtual void    InternalProcessAllTriangles(btInternalTriangleIndexCallback* callback,const btVector3& aabbMin,const btVector3& aabbMax) const;

                ///brute force method to calculate aabb
                void    calculateAabbBruteForce(btVector3& aabbMin,btVector3& aabbMax);

                /// get read and write access to a subpart of a triangle mesh
                /// this subpart has a continuous array of vertices and indices
                /// in this way the mesh can be handled as chunks of memory with striding
                /// very similar to OpenGL vertexarray support
                /// make a call to unLockVertexBase when the read and write access is finished  
                virtual void    getLockedVertexIndexBase(unsigned char **vertexbase, int& numverts,PHY_ScalarType& type, int& stride,unsigned char **indexbase,int & indexstride,int& numfaces,PHY_ScalarType& indicestype,int subpart=0)=0;
                
                virtual void    getLockedReadOnlyVertexIndexBase(const unsigned char **vertexbase, int& numverts,PHY_ScalarType& type, int& stride,const unsigned char **indexbase,int & indexstride,int& numfaces,PHY_ScalarType& indicestype,int subpart=0) const=0;
        
                /// unLockVertexBase finishes the access to a subpart of the triangle mesh
                /// make a call to unLockVertexBase when the read and write access (using getLockedVertexIndexBase) is finished
                virtual void    unLockVertexBase(int subpart)=0;

                virtual void    unLockReadOnlyVertexBase(int subpart) const=0;


                /// getNumSubParts returns the number of seperate subparts
                /// each subpart has a continuous array of vertices and indices
                virtual int             getNumSubParts() const=0;

                virtual void    preallocateVertices(int numverts)=0;
                virtual void    preallocateIndices(int numindices)=0;

                virtual bool    hasPremadeAabb() const { return false; }
                virtual void    setPremadeAabb(const btVector3& aabbMin, const btVector3& aabbMax ) const
                {
                        (void) aabbMin;
                        (void) aabbMax;
                }
                virtual void    getPremadeAabb(btVector3* aabbMin, btVector3* aabbMax ) const
        {
            (void) aabbMin;
            (void) aabbMax;
        }

                const btVector3&        getScaling() const {
                        return m_scaling;
                }
                void    setScaling(const btVector3& scaling)
                {
                        m_scaling = scaling;
                }

                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;


};

struct  btIntIndexData
{
        int     m_value;
};

struct  btShortIntIndexData
{
        short m_value;
        char m_pad[2];
};

struct  btShortIntIndexTripletData
{
        short   m_values[3];
        char    m_pad[2];
};

struct  btCharIndexTripletData
{
        unsigned char m_values[3];
        char    m_pad;
};


///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
struct  btMeshPartData
{
        btVector3FloatData                      *m_vertices3f;
        btVector3DoubleData                     *m_vertices3d;

        btIntIndexData                          *m_indices32;
        btShortIntIndexTripletData      *m_3indices16;
        btCharIndexTripletData          *m_3indices8;

        btShortIntIndexData                     *m_indices16;//backwards compatibility

        int                     m_numTriangles;//length of m_indices = m_numTriangles
        int                     m_numVertices;
};


///do not change those serialization structures, it requires an updated sBulletDNAstr/sBulletDNAstr64
struct  btStridingMeshInterfaceData
{
        btMeshPartData  *m_meshPartsPtr;
        btVector3FloatData      m_scaling;
        int     m_numMeshParts;
        char m_padding[4];
};




SIMD_FORCE_INLINE       int     btStridingMeshInterface::calculateSerializeBufferSize() const
{
        return sizeof(btStridingMeshInterfaceData);
}



#endif //BT_STRIDING_MESHINTERFACE_H