ExtVoxelTetrahedralizer.h

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#ifndef EXT_VOXEL_TETRAHEDRALIZER_H
#define EXT_VOXEL_TETRAHEDRALIZER_H
 
#include "ExtMultiList.h"
#include "ExtBVH.h"
#include "foundation/PxVec3.h"
#include "foundation/PxBounds3.h"
 
namespace physx
{
    namespace Ext
    {
 
        // ------------------------------------------------------------------------------
 
        class VoxelTetrahedralizer
        {
        public:
            VoxelTetrahedralizer();
 
            void clear();
            void createTetMesh(const PxArray<PxVec3>& verts, const PxArray<PxU32>& triIds,
                PxI32 resolution, PxI32 numRelaxationIters = 5, PxF32 relMinTetVolume = 0.05f);
 
            void readBack(PxArray<PxVec3>& tetVertices, PxArray<PxU32>& tetIndices);
 
        private:
            void voxelize(PxU32 resolution);
            void createTets(bool subdivBorder, PxU32 numTetsPerVoxel);
            void buildBVH();
            void createUniqueTetVertices();
            void findTargetPositions(PxF32 surfaceDist);
            void conserveVolume(PxF32 relMinVolume);
            void relax(PxI32 numIters, PxF32 relMinVolume);
 
            // input mesh
 
            PxArray<PxVec3> surfaceVerts;
            PxArray<PxI32> surfaceTriIds;
            PxBounds3 surfaceBounds;
 
            // voxel grid
 
            struct Voxel {
                void init(PxI32 _xi, PxI32 _yi, PxI32 _zi)
                {
                    xi = _xi; yi = _yi; zi = _zi;
                    for (PxI32 i = 0; i < 6; i++)
                        neighbors[i] = -1;
                    for (PxI32 i = 0; i < 8; i++)
                        ids[i] = -1;
                    parent = -1;
                    inner = false;
                }
                bool isAt(PxI32 _xi, PxI32 _yi, PxI32 _zi) {
                    return xi == _xi && yi == _yi && zi == _zi;
                }
                PxI32 xi, yi, zi;
                PxI32 neighbors[6];
                PxI32 parent;
                PxI32 ids[8];
                bool inner;
            };
 
            PxVec3 gridOrigin;
            PxF32 gridSpacing;
            PxArray<Voxel> voxels;
 
            BVHDesc bvh;
 
            // tet mesh
 
            PxArray<PxVec3> tetVerts;
            PxArray<PxVec3> origTetVerts;
            PxArray<PxI32> tetIds;
 
            // relaxation
 
            PxArray<bool> isSurfaceVert;
            PxArray<PxVec3> targetVertPos;
            PxArray<PxI32> queryTris;
            PxArray<PxI32> edgeIds;
        };
    }
}
 
#endif