303 lines
17 KiB
C++
303 lines
17 KiB
C++
/*******************************************************************************
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Copyright (c) 2005-2009 David Williams
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source
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distribution.
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*******************************************************************************/
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namespace PolyVox
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{
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template<typename VolumeType>
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Vector3DFloat computeCentralDifferenceGradient(const typename VolumeType::Sampler& volIter)
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{
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//FIXME - bitwise way of doing this?
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typename VolumeType::VoxelType voxel1nx = volIter.peekVoxel1nx0py0pz() > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1px = volIter.peekVoxel1px0py0pz() > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1ny = volIter.peekVoxel0px1ny0pz() > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1py = volIter.peekVoxel0px1py0pz() > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1nz = volIter.peekVoxel0px0py1nz() > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1pz = volIter.peekVoxel0px0py1pz() > 0 ? 1: 0;
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return Vector3DFloat
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(
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static_cast<float>(voxel1nx) - static_cast<float>(voxel1px),
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static_cast<float>(voxel1ny) - static_cast<float>(voxel1py),
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static_cast<float>(voxel1nz) - static_cast<float>(voxel1pz)
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);
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}
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template<typename VolumeType>
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Vector3DFloat computeDecimatedCentralDifferenceGradient(const typename VolumeType::Sampler& volIter)
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{
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const int32_t x = volIter.getPosition().getX();
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const int32_t y = volIter.getPosition().getY();
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const int32_t z = volIter.getPosition().getZ();
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//FIXME - bitwise way of doing this?
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typename VolumeType::VoxelType voxel1nx = volIter.getVoxel(x-2, y ,z ) > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1px = volIter.getVoxel(x-2, y ,z ) > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1ny = volIter.getVoxel(x , y-2,z ) > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1py = volIter.getVoxel(x , y-2,z ) > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1nz = volIter.getVoxel(x , y ,z-2) > 0 ? 1: 0;
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typename VolumeType::VoxelType voxel1pz = volIter.getVoxel(x , y ,z-2) > 0 ? 1: 0;
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return Vector3DFloat
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(
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static_cast<float>(voxel1nx) - static_cast<float>(voxel1px),
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static_cast<float>(voxel1ny) - static_cast<float>(voxel1py),
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static_cast<float>(voxel1nz) - static_cast<float>(voxel1pz)
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);
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}
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template<typename VolumeType>
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Vector3DFloat computeSmoothCentralDifferenceGradient(typename VolumeType::Sampler& volIter)
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{
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int32_t initialX = volIter.getPosition().getX();
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int32_t initialY = volIter.getPosition().getY();
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int32_t initialZ = volIter.getPosition().getZ();
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//FIXME - bitwise way of doing this?
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volIter.setPosition(initialX-1, initialY, initialZ);
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float voxel1nx = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY, initialZ);
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float voxel1px = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX, initialY-1, initialZ);
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float voxel1ny = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX, initialY+1, initialZ);
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float voxel1py = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX, initialY, initialZ-1);
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float voxel1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX, initialY, initialZ+1);
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float voxel1pz = computeSmoothedVoxel(volIter);
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return Vector3DFloat
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(
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voxel1nx - voxel1px,
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voxel1ny - voxel1py,
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voxel1nz - voxel1pz
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);
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}
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template<typename VolumeType>
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Vector3DFloat computeSobelGradient(const typename VolumeType::Sampler& volIter)
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{
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static const int weights[3][3][3] = { { {2,3,2}, {3,6,3}, {2,3,2} }, {
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{3,6,3}, {6,0,6}, {3,6,3} }, { {2,3,2}, {3,6,3}, {2,3,2} } };
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const typename VolumeType::VoxelType pVoxel1nx1ny1nz = volIter.peekVoxel1nx1ny1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx1ny0pz = volIter.peekVoxel1nx1ny0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx1ny1pz = volIter.peekVoxel1nx1ny1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx0py1nz = volIter.peekVoxel1nx0py1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx0py0pz = volIter.peekVoxel1nx0py0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx0py1pz = volIter.peekVoxel1nx0py1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx1py1nz = volIter.peekVoxel1nx1py1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx1py0pz = volIter.peekVoxel1nx1py0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1nx1py1pz = volIter.peekVoxel1nx1py1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px1ny1nz = volIter.peekVoxel0px1ny1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px1ny0pz = volIter.peekVoxel0px1ny0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px1ny1pz = volIter.peekVoxel0px1ny1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px0py1nz = volIter.peekVoxel0px0py1nz() > 0 ? 1: 0;
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//const VolumeType::VoxelType pVoxel0px0py0pz = volIter.peekVoxel0px0py0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px0py1pz = volIter.peekVoxel0px0py1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px1py1nz = volIter.peekVoxel0px1py1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px1py0pz = volIter.peekVoxel0px1py0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel0px1py1pz = volIter.peekVoxel0px1py1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px1ny1nz = volIter.peekVoxel1px1ny1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px1ny0pz = volIter.peekVoxel1px1ny0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px1ny1pz = volIter.peekVoxel1px1ny1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px0py1nz = volIter.peekVoxel1px0py1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px0py0pz = volIter.peekVoxel1px0py0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px0py1pz = volIter.peekVoxel1px0py1pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px1py1nz = volIter.peekVoxel1px1py1nz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px1py0pz = volIter.peekVoxel1px1py0pz() > 0 ? 1: 0;
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const typename VolumeType::VoxelType pVoxel1px1py1pz = volIter.peekVoxel1px1py1pz() > 0 ? 1: 0;
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const int xGrad(- weights[0][0][0] * pVoxel1nx1ny1nz -
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weights[1][0][0] * pVoxel1nx1ny0pz - weights[2][0][0] *
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pVoxel1nx1ny1pz - weights[0][1][0] * pVoxel1nx0py1nz -
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weights[1][1][0] * pVoxel1nx0py0pz - weights[2][1][0] *
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pVoxel1nx0py1pz - weights[0][2][0] * pVoxel1nx1py1nz -
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weights[1][2][0] * pVoxel1nx1py0pz - weights[2][2][0] *
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pVoxel1nx1py1pz + weights[0][0][2] * pVoxel1px1ny1nz +
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weights[1][0][2] * pVoxel1px1ny0pz + weights[2][0][2] *
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pVoxel1px1ny1pz + weights[0][1][2] * pVoxel1px0py1nz +
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weights[1][1][2] * pVoxel1px0py0pz + weights[2][1][2] *
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pVoxel1px0py1pz + weights[0][2][2] * pVoxel1px1py1nz +
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weights[1][2][2] * pVoxel1px1py0pz + weights[2][2][2] *
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pVoxel1px1py1pz);
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const int yGrad(- weights[0][0][0] * pVoxel1nx1ny1nz -
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weights[1][0][0] * pVoxel1nx1ny0pz - weights[2][0][0] *
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pVoxel1nx1ny1pz + weights[0][2][0] * pVoxel1nx1py1nz +
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weights[1][2][0] * pVoxel1nx1py0pz + weights[2][2][0] *
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pVoxel1nx1py1pz - weights[0][0][1] * pVoxel0px1ny1nz -
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weights[1][0][1] * pVoxel0px1ny0pz - weights[2][0][1] *
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pVoxel0px1ny1pz + weights[0][2][1] * pVoxel0px1py1nz +
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weights[1][2][1] * pVoxel0px1py0pz + weights[2][2][1] *
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pVoxel0px1py1pz - weights[0][0][2] * pVoxel1px1ny1nz -
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weights[1][0][2] * pVoxel1px1ny0pz - weights[2][0][2] *
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pVoxel1px1ny1pz + weights[0][2][2] * pVoxel1px1py1nz +
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weights[1][2][2] * pVoxel1px1py0pz + weights[2][2][2] *
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pVoxel1px1py1pz);
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const int zGrad(- weights[0][0][0] * pVoxel1nx1ny1nz +
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weights[2][0][0] * pVoxel1nx1ny1pz - weights[0][1][0] *
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pVoxel1nx0py1nz + weights[2][1][0] * pVoxel1nx0py1pz -
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weights[0][2][0] * pVoxel1nx1py1nz + weights[2][2][0] *
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pVoxel1nx1py1pz - weights[0][0][1] * pVoxel0px1ny1nz +
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weights[2][0][1] * pVoxel0px1ny1pz - weights[0][1][1] *
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pVoxel0px0py1nz + weights[2][1][1] * pVoxel0px0py1pz -
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weights[0][2][1] * pVoxel0px1py1nz + weights[2][2][1] *
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pVoxel0px1py1pz - weights[0][0][2] * pVoxel1px1ny1nz +
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weights[2][0][2] * pVoxel1px1ny1pz - weights[0][1][2] *
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pVoxel1px0py1nz + weights[2][1][2] * pVoxel1px0py1pz -
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weights[0][2][2] * pVoxel1px1py1nz + weights[2][2][2] *
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pVoxel1px1py1pz);
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//Note: The above actually give gradients going from low density to high density.
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//For our normals we want the the other way around, so we switch the components as we return them.
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return Vector3DFloat(static_cast<float>(-xGrad),static_cast<float>(-yGrad),static_cast<float>(-zGrad));
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}
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template<typename VolumeType>
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Vector3DFloat computeSmoothSobelGradient(typename VolumeType::Sampler& volIter)
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{
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static const int weights[3][3][3] = { { {2,3,2}, {3,6,3}, {2,3,2} }, {
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{3,6,3}, {6,0,6}, {3,6,3} }, { {2,3,2}, {3,6,3}, {2,3,2} } };
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int32_t initialX = volIter.getPosition().getX();
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int32_t initialY = volIter.getPosition().getY();
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int32_t initialZ = volIter.getPosition().getZ();
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volIter.setPosition(initialX-1, initialY-1, initialZ-1); const float pVoxel1nx1ny1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY-1, initialZ ); const float pVoxel1nx1ny0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY-1, initialZ+1); const float pVoxel1nx1ny1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY , initialZ-1); const float pVoxel1nx0py1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY , initialZ ); const float pVoxel1nx0py0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY , initialZ+1); const float pVoxel1nx0py1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY+1, initialZ-1); const float pVoxel1nx1py1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY+1, initialZ ); const float pVoxel1nx1py0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX-1, initialY+1, initialZ+1); const float pVoxel1nx1py1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY-1, initialZ-1); const float pVoxel0px1ny1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY-1, initialZ ); const float pVoxel0px1ny0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY-1, initialZ+1); const float pVoxel0px1ny1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY , initialZ-1); const float pVoxel0px0py1nz = computeSmoothedVoxel(volIter);
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//volIter.setPosition(initialX , initialY , initialZ ); const float pVoxel0px0py0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY , initialZ+1); const float pVoxel0px0py1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY+1, initialZ-1); const float pVoxel0px1py1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY+1, initialZ ); const float pVoxel0px1py0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX , initialY+1, initialZ+1); const float pVoxel0px1py1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY-1, initialZ-1); const float pVoxel1px1ny1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY-1, initialZ ); const float pVoxel1px1ny0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY-1, initialZ+1); const float pVoxel1px1ny1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY , initialZ-1); const float pVoxel1px0py1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY , initialZ ); const float pVoxel1px0py0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY , initialZ+1); const float pVoxel1px0py1pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY+1, initialZ-1); const float pVoxel1px1py1nz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY+1, initialZ ); const float pVoxel1px1py0pz = computeSmoothedVoxel(volIter);
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volIter.setPosition(initialX+1, initialY+1, initialZ+1); const float pVoxel1px1py1pz = computeSmoothedVoxel(volIter);
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/*const VoxelType pVoxel1nx1ny1nz = volIter.peekVoxel1nx1ny1nz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx1ny0pz = volIter.peekVoxel1nx1ny0pz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx1ny1pz = volIter.peekVoxel1nx1ny1pz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx0py1nz = volIter.peekVoxel1nx0py1nz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx0py0pz = volIter.peekVoxel1nx0py0pz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx0py1pz = volIter.peekVoxel1nx0py1pz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx1py1nz = volIter.peekVoxel1nx1py1nz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx1py0pz = volIter.peekVoxel1nx1py0pz() > 0 ? 1: 0;
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const VoxelType pVoxel1nx1py1pz = volIter.peekVoxel1nx1py1pz() > 0 ? 1: 0;
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const VoxelType pVoxel0px1ny1nz = volIter.peekVoxel0px1ny1nz() > 0 ? 1: 0;
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const VoxelType pVoxel0px1ny0pz = volIter.peekVoxel0px1ny0pz() > 0 ? 1: 0;
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const VoxelType pVoxel0px1ny1pz = volIter.peekVoxel0px1ny1pz() > 0 ? 1: 0;
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const VoxelType pVoxel0px0py1nz = volIter.peekVoxel0px0py1nz() > 0 ? 1: 0;
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//const VoxelType pVoxel0px0py0pz = volIter.peekVoxel0px0py0pz() > 0 ? 1: 0;
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const VoxelType pVoxel0px0py1pz = volIter.peekVoxel0px0py1pz() > 0 ? 1: 0;
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const VoxelType pVoxel0px1py1nz = volIter.peekVoxel0px1py1nz() > 0 ? 1: 0;
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const VoxelType pVoxel0px1py0pz = volIter.peekVoxel0px1py0pz() > 0 ? 1: 0;
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const VoxelType pVoxel0px1py1pz = volIter.peekVoxel0px1py1pz() > 0 ? 1: 0;
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const VoxelType pVoxel1px1ny1nz = volIter.peekVoxel1px1ny1nz() > 0 ? 1: 0;
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const VoxelType pVoxel1px1ny0pz = volIter.peekVoxel1px1ny0pz() > 0 ? 1: 0;
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const VoxelType pVoxel1px1ny1pz = volIter.peekVoxel1px1ny1pz() > 0 ? 1: 0;
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const VoxelType pVoxel1px0py1nz = volIter.peekVoxel1px0py1nz() > 0 ? 1: 0;
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const VoxelType pVoxel1px0py0pz = volIter.peekVoxel1px0py0pz() > 0 ? 1: 0;
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const VoxelType pVoxel1px0py1pz = volIter.peekVoxel1px0py1pz() > 0 ? 1: 0;
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const VoxelType pVoxel1px1py1nz = volIter.peekVoxel1px1py1nz() > 0 ? 1: 0;
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const VoxelType pVoxel1px1py0pz = volIter.peekVoxel1px1py0pz() > 0 ? 1: 0;
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const VoxelType pVoxel1px1py1pz = volIter.peekVoxel1px1py1pz() > 0 ? 1: 0;*/
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const float xGrad(- weights[0][0][0] * pVoxel1nx1ny1nz -
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weights[1][0][0] * pVoxel1nx1ny0pz - weights[2][0][0] *
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pVoxel1nx1ny1pz - weights[0][1][0] * pVoxel1nx0py1nz -
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weights[1][1][0] * pVoxel1nx0py0pz - weights[2][1][0] *
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pVoxel1nx0py1pz - weights[0][2][0] * pVoxel1nx1py1nz -
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weights[1][2][0] * pVoxel1nx1py0pz - weights[2][2][0] *
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pVoxel1nx1py1pz + weights[0][0][2] * pVoxel1px1ny1nz +
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weights[1][0][2] * pVoxel1px1ny0pz + weights[2][0][2] *
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pVoxel1px1ny1pz + weights[0][1][2] * pVoxel1px0py1nz +
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weights[1][1][2] * pVoxel1px0py0pz + weights[2][1][2] *
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pVoxel1px0py1pz + weights[0][2][2] * pVoxel1px1py1nz +
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weights[1][2][2] * pVoxel1px1py0pz + weights[2][2][2] *
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pVoxel1px1py1pz);
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const float yGrad(- weights[0][0][0] * pVoxel1nx1ny1nz -
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weights[1][0][0] * pVoxel1nx1ny0pz - weights[2][0][0] *
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pVoxel1nx1ny1pz + weights[0][2][0] * pVoxel1nx1py1nz +
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weights[1][2][0] * pVoxel1nx1py0pz + weights[2][2][0] *
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pVoxel1nx1py1pz - weights[0][0][1] * pVoxel0px1ny1nz -
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weights[1][0][1] * pVoxel0px1ny0pz - weights[2][0][1] *
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pVoxel0px1ny1pz + weights[0][2][1] * pVoxel0px1py1nz +
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weights[1][2][1] * pVoxel0px1py0pz + weights[2][2][1] *
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pVoxel0px1py1pz - weights[0][0][2] * pVoxel1px1ny1nz -
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weights[1][0][2] * pVoxel1px1ny0pz - weights[2][0][2] *
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pVoxel1px1ny1pz + weights[0][2][2] * pVoxel1px1py1nz +
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weights[1][2][2] * pVoxel1px1py0pz + weights[2][2][2] *
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pVoxel1px1py1pz);
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const float zGrad(- weights[0][0][0] * pVoxel1nx1ny1nz +
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weights[2][0][0] * pVoxel1nx1ny1pz - weights[0][1][0] *
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pVoxel1nx0py1nz + weights[2][1][0] * pVoxel1nx0py1pz -
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weights[0][2][0] * pVoxel1nx1py1nz + weights[2][2][0] *
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pVoxel1nx1py1pz - weights[0][0][1] * pVoxel0px1ny1nz +
|
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weights[2][0][1] * pVoxel0px1ny1pz - weights[0][1][1] *
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pVoxel0px0py1nz + weights[2][1][1] * pVoxel0px0py1pz -
|
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weights[0][2][1] * pVoxel0px1py1nz + weights[2][2][1] *
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pVoxel0px1py1pz - weights[0][0][2] * pVoxel1px1ny1nz +
|
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weights[2][0][2] * pVoxel1px1ny1pz - weights[0][1][2] *
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pVoxel1px0py1nz + weights[2][1][2] * pVoxel1px0py1pz -
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weights[0][2][2] * pVoxel1px1py1nz + weights[2][2][2] *
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pVoxel1px1py1pz);
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//Note: The above actually give gradients going from low density to high density.
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//For our normals we want the the other way around, so we switch the components as we return them.
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return Vector3DFloat(-xGrad,-yGrad,-zGrad);
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}
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}
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