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David Williams 2015-05-25 16:45:52 +02:00
parent b353cd1ce8
commit e0ce93acb1
1 changed files with 17 additions and 8 deletions
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include/PolyVox/MarchingCubesSurfaceExtractor.inl
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@ -97,23 +97,32 @@ namespace PolyVox
uint8_t iCubeIndex = 0; uint8_t iCubeIndex = 0;
uint8_t iPreviousCubeIndexX = uPreviousCell; // Four bits of our cube index are obtained by looking at the cube index for
iPreviousCubeIndexX &= 170; //170 = 128+32+8+2 // the previous slice and copying four of those bits into their new positions.
iPreviousCubeIndexX >>= 1; uint8_t iPreviousCubeIndexZ = pPreviousSliceBitmask(uXRegSpace, uYRegSpace);
iCubeIndex |= iPreviousCubeIndexX; iPreviousCubeIndexZ >>= 4;
iCubeIndex |= iPreviousCubeIndexZ;
// Two bits of our cube index are obtained by looking at the cube index for
// the previous row and copying two of those bits into their new positions.
uint8_t iPreviousCubeIndexY = pPreviousRowBitmask(uXRegSpace); uint8_t iPreviousCubeIndexY = pPreviousRowBitmask(uXRegSpace);
iPreviousCubeIndexY &= 204; //204 = 128+64+8+4 iPreviousCubeIndexY &= 204; //204 = 128+64+8+4
iPreviousCubeIndexY >>= 2; iPreviousCubeIndexY >>= 2;
iCubeIndex |= iPreviousCubeIndexY; iCubeIndex |= iPreviousCubeIndexY;
uint8_t iPreviousCubeIndexZ = pPreviousSliceBitmask(uXRegSpace, uYRegSpace); // One bit of our cube index are obtained by looking at the cube index for
iPreviousCubeIndexZ >>= 4; // the previous cell and copying one of those bits into it's new position.
iCubeIndex |= iPreviousCubeIndexZ; uint8_t iPreviousCubeIndexX = uPreviousCell;
iPreviousCubeIndexX &= 170; //170 = 128+32+8+2
iPreviousCubeIndexX >>= 1;
iCubeIndex |= iPreviousCubeIndexX;
typename VolumeType::VoxelType v111 = sampler.peekVoxel0px0py0pz(); // The last bit of our cube index is obtained by looking
// at the relevant voxel and comparing it to the threshold
typename VolumeType::VoxelType v111 = sampler.getVoxel();
if (m_controller.convertToDensity(v111) < m_tThreshold) iCubeIndex |= 128; if (m_controller.convertToDensity(v111) < m_tThreshold) iCubeIndex |= 128;
// The current value becomes the previous value, ready for the next iteration.
uPreviousCell = iCubeIndex; uPreviousCell = iCubeIndex;
pPreviousRowBitmask(uXRegSpace) = iCubeIndex; pPreviousRowBitmask(uXRegSpace) = iCubeIndex;
pPreviousSliceBitmask(uXRegSpace, uYRegSpace) = iCubeIndex; pPreviousSliceBitmask(uXRegSpace, uYRegSpace) = iCubeIndex;