1171 lines
42 KiB
C++
1171 lines
42 KiB
C++
#include "SurfaceExtractors.h"
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#include "BlockVolume.h"
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#include "GradientEstimators.h"
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#include "IndexedSurfacePatch.h"
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#include "MarchingCubesTables.h"
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#include "Region.h"
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#include "RegionGeometry.h"
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#include "VolumeChangeTracker.h"
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#include "BlockVolumeIterator.h"
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#include <algorithm>
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using namespace boost;
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namespace PolyVox
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{
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std::list<RegionGeometry> getChangedRegionGeometry(VolumeChangeTracker& volume)
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{
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std::list<Region> listChangedRegions;
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volume.getChangedRegions(listChangedRegions);
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std::list<RegionGeometry> listChangedRegionGeometry;
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for(std::list<Region>::const_iterator iterChangedRegions = listChangedRegions.begin(); iterChangedRegions != listChangedRegions.end(); ++iterChangedRegions)
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{
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//Generate the surface
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RegionGeometry regionGeometry;
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regionGeometry.m_patchSingleMaterial = new IndexedSurfacePatch(false);
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regionGeometry.m_v3dRegionPosition = iterChangedRegions->getLowerCorner();
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generateRoughMeshDataForRegion(volume.getVolumeData(), *iterChangedRegions, regionGeometry.m_patchSingleMaterial);
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//genMultiFromSingle(regionGeometry.m_patchSingleMaterial, regionGeometry.m_patchMultiMaterial);
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regionGeometry.m_bContainsSingleMaterialPatch = regionGeometry.m_patchSingleMaterial->getVertices().size() > 0;
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regionGeometry.m_bIsEmpty = (regionGeometry.m_patchSingleMaterial->getVertices().size() == 0) || (regionGeometry.m_patchSingleMaterial->getIndices().size() == 0);
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listChangedRegionGeometry.push_back(regionGeometry);
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}
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return listChangedRegionGeometry;
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}
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boost::uint32_t getIndex(boost::uint32_t x, boost::uint32_t y)
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{
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return x + (y * (POLYVOX_REGION_SIDE_LENGTH+1));
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}
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void generateRoughMeshDataForRegion(BlockVolume<uint8_t>* volumeData, Region region, IndexedSurfacePatch* singleMaterialPatch)
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{
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singleMaterialPatch->m_vecVertices.clear();
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singleMaterialPatch->m_vecTriangleIndices.clear();
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//For edge indices
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boost::int32_t* vertexIndicesX0 = new boost::int32_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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boost::int32_t* vertexIndicesY0 = new boost::int32_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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boost::int32_t* vertexIndicesZ0 = new boost::int32_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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boost::int32_t* vertexIndicesX1 = new boost::int32_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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boost::int32_t* vertexIndicesY1 = new boost::int32_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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boost::int32_t* vertexIndicesZ1 = new boost::int32_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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//Cell bitmasks
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boost::uint8_t* bitmask0 = new boost::uint8_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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boost::uint8_t* bitmask1 = new boost::uint8_t[(POLYVOX_REGION_SIDE_LENGTH+1) * (POLYVOX_REGION_SIDE_LENGTH+1)];
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//When generating the mesh for a region we actually look one voxel outside it in the
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// back, bottom, right direction. Protect against access violations by cropping region here
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Region regVolume = volumeData->getEnclosingRegion();
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regVolume.setUpperCorner(regVolume.getUpperCorner() - Vector3DInt32(1,1,1));
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region.cropTo(regVolume);
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//Offset from volume corner
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const Vector3DFloat offset = static_cast<Vector3DFloat>(region.getLowerCorner());
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//Temporary space use to store the vertices
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Vector3DFloat vertlist[12];
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uint8_t vertMaterials[12];
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//Create a region corresponding to the first slice
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Region regSlice0(region);
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regSlice0.setUpperCorner(Vector3DInt32(regSlice0.getUpperCorner().getX(),regSlice0.getUpperCorner().getY(),regSlice0.getLowerCorner().getZ()));
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//Iterator to access the volume data
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BlockVolumeIterator<boost::uint8_t> volIter(*volumeData);
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//Compute bitmask for initial slice
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boost::uint32_t uNoOfNonEmptyCellsForSlice0 = computeInitialRoughBitmaskForSlice(volIter, regSlice0, offset, bitmask0);
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if(uNoOfNonEmptyCellsForSlice0 != 0)
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{
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//If there were some non-empty cells then generate initial slice vertices for them
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generateRoughVerticesForSlice(volIter,regSlice0, offset, bitmask0, singleMaterialPatch, vertexIndicesX0, vertexIndicesY0, vertexIndicesZ0, /*regTwoSlice.getUpperCorner(),*/ vertlist, vertMaterials);
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}
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for(boost::uint32_t uSlice = 0; ((uSlice <= POLYVOX_REGION_SIDE_LENGTH-1) && (uSlice + offset.getZ() < region.getUpperCorner().getZ())); ++uSlice)
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{
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Region regSlice1(regSlice0);
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regSlice1.shift(Vector3DInt32(0,0,1));
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boost::uint32_t uNoOfNonEmptyCellsForSlice1 = computeRoughBitmaskForSliceFromPrevious(volIter, regSlice1, offset, bitmask1, bitmask0);
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if(uNoOfNonEmptyCellsForSlice1 != 0)
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{
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generateRoughVerticesForSlice(volIter,regSlice1, offset, bitmask1, singleMaterialPatch, vertexIndicesX1, vertexIndicesY1, vertexIndicesZ1, vertlist, vertMaterials);
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}
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if((uNoOfNonEmptyCellsForSlice0 != 0) || (uNoOfNonEmptyCellsForSlice1 != 0))
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{
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generateRoughIndicesForSlice(volIter, regSlice0, singleMaterialPatch, offset, bitmask0, bitmask1, vertexIndicesX0, vertexIndicesY0, vertexIndicesZ0, vertexIndicesX1, vertexIndicesY1, vertexIndicesZ1);
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}
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std::swap(uNoOfNonEmptyCellsForSlice0, uNoOfNonEmptyCellsForSlice1);
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std::swap(bitmask0, bitmask1);
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std::swap(vertexIndicesX0, vertexIndicesX1);
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std::swap(vertexIndicesY0, vertexIndicesY1);
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std::swap(vertexIndicesZ0, vertexIndicesZ1);
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regSlice0 = regSlice1;
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}
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delete[] bitmask0;
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delete[] bitmask1;
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delete[] vertexIndicesX0;
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delete[] vertexIndicesX1;
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delete[] vertexIndicesY0;
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delete[] vertexIndicesY1;
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delete[] vertexIndicesZ0;
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delete[] vertexIndicesZ1;
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std::vector<SurfaceVertex>::iterator iterSurfaceVertex = singleMaterialPatch->getVertices().begin();
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while(iterSurfaceVertex != singleMaterialPatch->getVertices().end())
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{
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Vector3DFloat tempNormal = computeNormal(volumeData, static_cast<Vector3DFloat>(iterSurfaceVertex->getPosition() + offset), CENTRAL_DIFFERENCE);
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const_cast<SurfaceVertex&>(*iterSurfaceVertex).setNormal(tempNormal);
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++iterSurfaceVertex;
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}
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}
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boost::uint32_t computeInitialRoughBitmaskForSlice(BlockVolumeIterator<uint8_t>& volIter, const Region& regSlice, const Vector3DFloat& offset, uint8_t* bitmask)
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{
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boost::uint32_t uNoOfNonEmptyCells = 0;
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//Iterate over each cell in the region
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volIter.setPosition(regSlice.getLowerCorner().getX(),regSlice.getLowerCorner().getY(), regSlice.getLowerCorner().getZ());
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volIter.setValidRegion(regSlice);
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do
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{
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//Current position
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const uint16_t x = volIter.getPosX() - offset.getX();
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const uint16_t y = volIter.getPosY() - offset.getY();
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//Determine the index into the edge table which tells us which vertices are inside of the surface
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uint8_t iCubeIndex = 0;
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if((x==0) && (y==0))
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{
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const uint8_t v000 = volIter.getVoxel();
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const uint8_t v100 = volIter.peekVoxel1px0py0pz();
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const uint8_t v010 = volIter.peekVoxel0px1py0pz();
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const uint8_t v110 = volIter.peekVoxel1px1py0pz();
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const uint8_t v001 = volIter.peekVoxel0px0py1pz();
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const uint8_t v101 = volIter.peekVoxel1px0py1pz();
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const uint8_t v011 = volIter.peekVoxel0px1py1pz();
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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if (v000 == 0) iCubeIndex |= 1;
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if (v100 == 0) iCubeIndex |= 2;
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if (v110 == 0) iCubeIndex |= 4;
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if (v010 == 0) iCubeIndex |= 8;
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if (v001 == 0) iCubeIndex |= 16;
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if (v101 == 0) iCubeIndex |= 32;
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if (v111 == 0) iCubeIndex |= 64;
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if (v011 == 0) iCubeIndex |= 128;
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}
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else if((x>0) && y==0)
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{
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const uint8_t v100 = volIter.peekVoxel1px0py0pz();
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const uint8_t v110 = volIter.peekVoxel1px1py0pz();
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const uint8_t v101 = volIter.peekVoxel1px0py1pz();
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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//x
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uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y)];
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uint8_t srcBit6 = iPreviousCubeIndexX & 64;
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uint8_t destBit7 = srcBit6 << 1;
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uint8_t srcBit5 = iPreviousCubeIndexX & 32;
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uint8_t destBit4 = srcBit5 >> 1;
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uint8_t srcBit2 = iPreviousCubeIndexX & 4;
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uint8_t destBit3 = srcBit2 << 1;
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uint8_t srcBit1 = iPreviousCubeIndexX & 2;
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uint8_t destBit0 = srcBit1 >> 1;
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iCubeIndex |= destBit0;
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if (v100 == 0) iCubeIndex |= 2;
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if (v110 == 0) iCubeIndex |= 4;
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iCubeIndex |= destBit3;
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iCubeIndex |= destBit4;
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if (v101 == 0) iCubeIndex |= 32;
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if (v111 == 0) iCubeIndex |= 64;
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iCubeIndex |= destBit7;
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}
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else if((x==0) && (y>0))
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{
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const uint8_t v010 = volIter.peekVoxel0px1py0pz();
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const uint8_t v110 = volIter.peekVoxel1px1py0pz();
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const uint8_t v011 = volIter.peekVoxel0px1py1pz();
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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//y
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uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1)];
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uint8_t srcBit7 = iPreviousCubeIndexY & 128;
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uint8_t destBit4 = srcBit7 >> 3;
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uint8_t srcBit6 = iPreviousCubeIndexY & 64;
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uint8_t destBit5 = srcBit6 >> 1;
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uint8_t srcBit3 = iPreviousCubeIndexY & 8;
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uint8_t destBit0 = srcBit3 >> 3;
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uint8_t srcBit2 = iPreviousCubeIndexY & 4;
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uint8_t destBit1 = srcBit2 >> 1;
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iCubeIndex |= destBit0;
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iCubeIndex |= destBit1;
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if (v110 == 0) iCubeIndex |= 4;
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if (v010 == 0) iCubeIndex |= 8;
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iCubeIndex |= destBit4;
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iCubeIndex |= destBit5;
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if (v111 == 0) iCubeIndex |= 64;
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if (v011 == 0) iCubeIndex |= 128;
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}
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else
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{
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const uint8_t v110 = volIter.peekVoxel1px1py0pz();
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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//y
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uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1)];
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uint8_t srcBit7 = iPreviousCubeIndexY & 128;
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uint8_t destBit4 = srcBit7 >> 3;
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uint8_t srcBit6 = iPreviousCubeIndexY & 64;
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uint8_t destBit5 = srcBit6 >> 1;
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uint8_t srcBit3 = iPreviousCubeIndexY & 8;
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uint8_t destBit0 = srcBit3 >> 3;
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uint8_t srcBit2 = iPreviousCubeIndexY & 4;
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uint8_t destBit1 = srcBit2 >> 1;
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//x
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uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y)];
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srcBit6 = iPreviousCubeIndexX & 64;
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uint8_t destBit7 = srcBit6 << 1;
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srcBit2 = iPreviousCubeIndexX & 4;
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uint8_t destBit3 = srcBit2 << 1;
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iCubeIndex |= destBit0;
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iCubeIndex |= destBit1;
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if (v110 == 0) iCubeIndex |= 4;
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iCubeIndex |= destBit3;
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iCubeIndex |= destBit4;
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iCubeIndex |= destBit5;
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if (v111 == 0) iCubeIndex |= 64;
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iCubeIndex |= destBit7;
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}
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//Save the bitmask
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bitmask[getIndex(x,y)] = iCubeIndex;
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if(edgeTable[iCubeIndex] != 0)
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{
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++uNoOfNonEmptyCells;
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}
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}while(volIter.moveForwardInRegionXYZ());//For each cell
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return uNoOfNonEmptyCells;
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}
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boost::uint32_t computeRoughBitmaskForSliceFromPrevious(BlockVolumeIterator<uint8_t>& volIter, const Region& regSlice, const Vector3DFloat& offset, uint8_t* bitmask, uint8_t* previousBitmask)
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{
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boost::uint32_t uNoOfNonEmptyCells = 0;
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//Iterate over each cell in the region
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volIter.setPosition(regSlice.getLowerCorner().getX(),regSlice.getLowerCorner().getY(), regSlice.getLowerCorner().getZ());
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volIter.setValidRegion(regSlice);
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do
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{
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//Current position
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const uint16_t x = volIter.getPosX() - offset.getX();
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const uint16_t y = volIter.getPosY() - offset.getY();
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//Determine the index into the edge table which tells us which vertices are inside of the surface
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uint8_t iCubeIndex = 0;
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if((x==0) && (y==0))
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{
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const uint8_t v001 = volIter.peekVoxel0px0py1pz();
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const uint8_t v101 = volIter.peekVoxel1px0py1pz();
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const uint8_t v011 = volIter.peekVoxel0px1py1pz();
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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//z
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uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y)];
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iCubeIndex = iPreviousCubeIndexZ >> 4;
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if (v001 == 0) iCubeIndex |= 16;
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if (v101 == 0) iCubeIndex |= 32;
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if (v111 == 0) iCubeIndex |= 64;
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if (v011 == 0) iCubeIndex |= 128;
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}
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else if((x>0) && y==0)
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{
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const uint8_t v101 = volIter.peekVoxel1px0py1pz();
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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//z
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uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y)];
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iCubeIndex = iPreviousCubeIndexZ >> 4;
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//x
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uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y)];
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uint8_t srcBit6 = iPreviousCubeIndexX & 64;
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uint8_t destBit7 = srcBit6 << 1;
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uint8_t srcBit5 = iPreviousCubeIndexX & 32;
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uint8_t destBit4 = srcBit5 >> 1;
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iCubeIndex |= destBit4;
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if (v101 == 0) iCubeIndex |= 32;
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if (v111 == 0) iCubeIndex |= 64;
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iCubeIndex |= destBit7;
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}
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else if((x==0) && (y>0))
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{
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const uint8_t v011 = volIter.peekVoxel0px1py1pz();
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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//z
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uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y)];
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iCubeIndex = iPreviousCubeIndexZ >> 4;
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//y
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uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1)];
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uint8_t srcBit7 = iPreviousCubeIndexY & 128;
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uint8_t destBit4 = srcBit7 >> 3;
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uint8_t srcBit6 = iPreviousCubeIndexY & 64;
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uint8_t destBit5 = srcBit6 >> 1;
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iCubeIndex |= destBit4;
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iCubeIndex |= destBit5;
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if (v111 == 0) iCubeIndex |= 64;
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if (v011 == 0) iCubeIndex |= 128;
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}
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else
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{
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const uint8_t v111 = volIter.peekVoxel1px1py1pz();
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//z
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uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y)];
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iCubeIndex = iPreviousCubeIndexZ >> 4;
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//y
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uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1)];
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uint8_t srcBit7 = iPreviousCubeIndexY & 128;
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uint8_t destBit4 = srcBit7 >> 3;
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uint8_t srcBit6 = iPreviousCubeIndexY & 64;
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uint8_t destBit5 = srcBit6 >> 1;
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//x
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uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y)];
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srcBit6 = iPreviousCubeIndexX & 64;
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uint8_t destBit7 = srcBit6 << 1;
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iCubeIndex |= destBit4;
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iCubeIndex |= destBit5;
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if (v111 == 0) iCubeIndex |= 64;
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iCubeIndex |= destBit7;
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}
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//Save the bitmask
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bitmask[getIndex(x,y)] = iCubeIndex;
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if(edgeTable[iCubeIndex] != 0)
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{
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++uNoOfNonEmptyCells;
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}
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}while(volIter.moveForwardInRegionXYZ());//For each cell
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return uNoOfNonEmptyCells;
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}
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void generateRoughVerticesForSlice(BlockVolumeIterator<uint8_t>& volIter, Region& regSlice, const Vector3DFloat& offset, uint8_t* bitmask, IndexedSurfacePatch* singleMaterialPatch,boost::int32_t vertexIndicesX[],boost::int32_t vertexIndicesY[],boost::int32_t vertexIndicesZ[], Vector3DFloat vertlist[], uint8_t vertMaterials[])
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{
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//Iterate over each cell in the region
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volIter.setPosition(regSlice.getLowerCorner().getX(),regSlice.getLowerCorner().getY(), regSlice.getLowerCorner().getZ());
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volIter.setValidRegion(regSlice);
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//while(volIter.moveForwardInRegionXYZ())
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do
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{
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//Current position
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const uint16_t x = volIter.getPosX() - offset.getX();
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const uint16_t y = volIter.getPosY() - offset.getY();
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const uint16_t z = volIter.getPosZ() - offset.getZ();
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const uint8_t v000 = volIter.getVoxel();
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//Determine the index into the edge table which tells us which vertices are inside of the surface
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uint8_t iCubeIndex = bitmask[getIndex(x,y)];
|
|
|
|
/* Cube is entirely in/out of the surface */
|
|
if (edgeTable[iCubeIndex] == 0)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
/* Find the vertices where the surface intersects the cube */
|
|
if (edgeTable[iCubeIndex] & 1)
|
|
{
|
|
if((x + offset.getX()) != regSlice.getUpperCorner().getX())
|
|
{
|
|
vertlist[0].setX(x + 0.5f);
|
|
vertlist[0].setY(y);
|
|
vertlist[0].setZ(z);
|
|
vertMaterials[0] = v000 | volIter.peekVoxel1px0py0pz(); //Because one of these is 0, the or operation takes the max.
|
|
SurfaceVertex surfaceVertex(vertlist[0],vertMaterials[0], 1.0);
|
|
singleMaterialPatch->m_vecVertices.push_back(surfaceVertex);
|
|
vertexIndicesX[getIndex(x,y)] = singleMaterialPatch->m_vecVertices.size()-1;
|
|
}
|
|
}
|
|
if (edgeTable[iCubeIndex] & 8)
|
|
{
|
|
if((y + offset.getY()) != regSlice.getUpperCorner().getY())
|
|
{
|
|
vertlist[3].setX(x);
|
|
vertlist[3].setY(y + 0.5f);
|
|
vertlist[3].setZ(z);
|
|
vertMaterials[3] = v000 | volIter.peekVoxel0px1py0pz();
|
|
SurfaceVertex surfaceVertex(vertlist[3],vertMaterials[3], 1.0);
|
|
singleMaterialPatch->m_vecVertices.push_back(surfaceVertex);
|
|
vertexIndicesY[getIndex(x,y)] = singleMaterialPatch->m_vecVertices.size()-1;
|
|
}
|
|
}
|
|
if (edgeTable[iCubeIndex] & 256)
|
|
{
|
|
//if((z + offset.getZ()) != upperCorner.getZ())
|
|
{
|
|
vertlist[8].setX(x);
|
|
vertlist[8].setY(y);
|
|
vertlist[8].setZ(z + 0.5f);
|
|
vertMaterials[8] = v000 | volIter.peekVoxel0px0py1pz();
|
|
SurfaceVertex surfaceVertex(vertlist[8],vertMaterials[8], 1.0);
|
|
singleMaterialPatch->m_vecVertices.push_back(surfaceVertex);
|
|
vertexIndicesZ[getIndex(x,y)] = singleMaterialPatch->m_vecVertices.size()-1;
|
|
}
|
|
}
|
|
}while(volIter.moveForwardInRegionXYZ());//For each cell
|
|
}
|
|
|
|
void generateRoughIndicesForSlice(BlockVolumeIterator<uint8_t>& volIter, const Region& regSlice, IndexedSurfacePatch* singleMaterialPatch, const Vector3DFloat& offset, uint8_t* bitmask0, uint8_t* bitmask1, boost::int32_t vertexIndicesX0[],boost::int32_t vertexIndicesY0[],boost::int32_t vertexIndicesZ0[], boost::int32_t vertexIndicesX1[],boost::int32_t vertexIndicesY1[],boost::int32_t vertexIndicesZ1[])
|
|
{
|
|
boost::uint32_t indlist[12];
|
|
|
|
Region regCroppedSlice(regSlice);
|
|
regCroppedSlice.setUpperCorner(regCroppedSlice.getUpperCorner() - Vector3DInt32(1,1,0));
|
|
|
|
volIter.setPosition(regCroppedSlice.getLowerCorner().getX(),regCroppedSlice.getLowerCorner().getY(), regCroppedSlice.getLowerCorner().getZ());
|
|
volIter.setValidRegion(regCroppedSlice);
|
|
do
|
|
{
|
|
//Current position
|
|
const uint16_t x = volIter.getPosX() - offset.getX();
|
|
const uint16_t y = volIter.getPosY() - offset.getY();
|
|
const uint16_t z = volIter.getPosZ() - offset.getZ();
|
|
|
|
//Determine the index into the edge table which tells us which vertices are inside of the surface
|
|
uint8_t iCubeIndex = bitmask0[getIndex(x,y)];
|
|
|
|
/* Cube is entirely in/out of the surface */
|
|
if (edgeTable[iCubeIndex] == 0)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
/* Find the vertices where the surface intersects the cube */
|
|
if (edgeTable[iCubeIndex] & 1)
|
|
{
|
|
indlist[0] = vertexIndicesX0[getIndex(x,y)];
|
|
assert(indlist[0] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 2)
|
|
{
|
|
indlist[1] = vertexIndicesY0[getIndex(x+1,y)];
|
|
assert(indlist[1] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 4)
|
|
{
|
|
indlist[2] = vertexIndicesX0[getIndex(x,y+1)];
|
|
assert(indlist[2] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 8)
|
|
{
|
|
indlist[3] = vertexIndicesY0[getIndex(x,y)];
|
|
assert(indlist[3] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 16)
|
|
{
|
|
indlist[4] = vertexIndicesX1[getIndex(x,y)];
|
|
assert(indlist[4] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 32)
|
|
{
|
|
indlist[5] = vertexIndicesY1[getIndex(x+1,y)];
|
|
assert(indlist[5] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 64)
|
|
{
|
|
indlist[6] = vertexIndicesX1[getIndex(x,y+1)];
|
|
assert(indlist[6] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 128)
|
|
{
|
|
indlist[7] = vertexIndicesY1[getIndex(x,y)];
|
|
assert(indlist[7] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 256)
|
|
{
|
|
indlist[8] = vertexIndicesZ0[getIndex(x,y)];
|
|
assert(indlist[8] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 512)
|
|
{
|
|
indlist[9] = vertexIndicesZ0[getIndex(x+1,y)];
|
|
assert(indlist[9] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 1024)
|
|
{
|
|
indlist[10] = vertexIndicesZ0[getIndex(x+1,y+1)];
|
|
assert(indlist[10] != -1);
|
|
}
|
|
if (edgeTable[iCubeIndex] & 2048)
|
|
{
|
|
indlist[11] = vertexIndicesZ0[getIndex(x,y+1)];
|
|
assert(indlist[11] != -1);
|
|
}
|
|
|
|
for (int i=0;triTable[iCubeIndex][i]!=-1;i+=3)
|
|
{
|
|
boost::uint32_t ind0 = indlist[triTable[iCubeIndex][i ]];
|
|
boost::uint32_t ind1 = indlist[triTable[iCubeIndex][i+1]];
|
|
boost::uint32_t ind2 = indlist[triTable[iCubeIndex][i+2]];
|
|
|
|
singleMaterialPatch->m_vecTriangleIndices.push_back(ind0);
|
|
singleMaterialPatch->m_vecTriangleIndices.push_back(ind1);
|
|
singleMaterialPatch->m_vecTriangleIndices.push_back(ind2);
|
|
}//For each triangle
|
|
}while(volIter.moveForwardInRegionXYZ());//For each cell
|
|
}
|
|
|
|
void generateReferenceMeshDataForRegion(BlockVolume<uint8_t>* volumeData, Region region, IndexedSurfacePatch* singleMaterialPatch)
|
|
{
|
|
//When generating the mesh for a region we actually look one voxel outside it in the
|
|
// back, bottom, right direction. Protect against access violations by cropping region here
|
|
Region regVolume = volumeData->getEnclosingRegion();
|
|
//regVolume.setUpperCorner(regVolume.getUpperCorner() - Vector3DInt32(1,1,1));
|
|
region.cropTo(regVolume);
|
|
region.setUpperCorner(region.getUpperCorner() - Vector3DInt32(1,1,1));
|
|
|
|
//Offset from lower block corner
|
|
const Vector3DFloat offset = static_cast<Vector3DFloat>(region.getLowerCorner());
|
|
|
|
Vector3DFloat vertlist[12];
|
|
uint8_t vertMaterials[12];
|
|
BlockVolumeIterator<boost::uint8_t> volIter(*volumeData);
|
|
volIter.setValidRegion(region);
|
|
|
|
//////////////////////////////////////////////////////////////////////////
|
|
//Get mesh data
|
|
//////////////////////////////////////////////////////////////////////////
|
|
|
|
//Iterate over each cell in the region
|
|
volIter.setPosition(region.getLowerCorner().getX(),region.getLowerCorner().getY(), region.getLowerCorner().getZ());
|
|
while(volIter.moveForwardInRegionXYZ())
|
|
{
|
|
//Current position
|
|
const uint16_t x = volIter.getPosX();
|
|
const uint16_t y = volIter.getPosY();
|
|
const uint16_t z = volIter.getPosZ();
|
|
|
|
//Voxels values
|
|
const uint8_t v000 = volIter.getVoxel();
|
|
const uint8_t v100 = volIter.peekVoxel1px0py0pz();
|
|
const uint8_t v010 = volIter.peekVoxel0px1py0pz();
|
|
const uint8_t v110 = volIter.peekVoxel1px1py0pz();
|
|
const uint8_t v001 = volIter.peekVoxel0px0py1pz();
|
|
const uint8_t v101 = volIter.peekVoxel1px0py1pz();
|
|
const uint8_t v011 = volIter.peekVoxel0px1py1pz();
|
|
const uint8_t v111 = volIter.peekVoxel1px1py1pz();
|
|
|
|
//Determine the index into the edge table which tells us which vertices are inside of the surface
|
|
uint8_t iCubeIndex = 0;
|
|
|
|
if (v000 == 0) iCubeIndex |= 1;
|
|
if (v100 == 0) iCubeIndex |= 2;
|
|
if (v110 == 0) iCubeIndex |= 4;
|
|
if (v010 == 0) iCubeIndex |= 8;
|
|
if (v001 == 0) iCubeIndex |= 16;
|
|
if (v101 == 0) iCubeIndex |= 32;
|
|
if (v111 == 0) iCubeIndex |= 64;
|
|
if (v011 == 0) iCubeIndex |= 128;
|
|
|
|
/* Cube is entirely in/out of the surface */
|
|
if (edgeTable[iCubeIndex] == 0)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
/* Find the vertices where the surface intersects the cube */
|
|
if (edgeTable[iCubeIndex] & 1)
|
|
{
|
|
vertlist[0].setX(x + 0.5f);
|
|
vertlist[0].setY(y);
|
|
vertlist[0].setZ(z);
|
|
vertMaterials[0] = v000 | v100; //Because one of these is 0, the or operation takes the max.
|
|
}
|
|
if (edgeTable[iCubeIndex] & 2)
|
|
{
|
|
vertlist[1].setX(x + 1.0f);
|
|
vertlist[1].setY(y + 0.5f);
|
|
vertlist[1].setZ(z);
|
|
vertMaterials[1] = v100 | v110;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 4)
|
|
{
|
|
vertlist[2].setX(x + 0.5f);
|
|
vertlist[2].setY(y + 1.0f);
|
|
vertlist[2].setZ(z);
|
|
vertMaterials[2] = v010 | v110;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 8)
|
|
{
|
|
vertlist[3].setX(x);
|
|
vertlist[3].setY(y + 0.5f);
|
|
vertlist[3].setZ(z);
|
|
vertMaterials[3] = v000 | v010;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 16)
|
|
{
|
|
vertlist[4].setX(x + 0.5f);
|
|
vertlist[4].setY(y);
|
|
vertlist[4].setZ(z + 1.0f);
|
|
vertMaterials[4] = v001 | v101;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 32)
|
|
{
|
|
vertlist[5].setX(x + 1.0f);
|
|
vertlist[5].setY(y + 0.5f);
|
|
vertlist[5].setZ(z + 1.0f);
|
|
vertMaterials[5] = v101 | v111;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 64)
|
|
{
|
|
vertlist[6].setX(x + 0.5f);
|
|
vertlist[6].setY(y + 1.0f);
|
|
vertlist[6].setZ(z + 1.0f);
|
|
vertMaterials[6] = v011 | v111;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 128)
|
|
{
|
|
vertlist[7].setX(x);
|
|
vertlist[7].setY(y + 0.5f);
|
|
vertlist[7].setZ(z + 1.0f);
|
|
vertMaterials[7] = v001 | v011;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 256)
|
|
{
|
|
vertlist[8].setX(x);
|
|
vertlist[8].setY(y);
|
|
vertlist[8].setZ(z + 0.5f);
|
|
vertMaterials[8] = v000 | v001;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 512)
|
|
{
|
|
vertlist[9].setX(x + 1.0f);
|
|
vertlist[9].setY(y);
|
|
vertlist[9].setZ(z + 0.5f);
|
|
vertMaterials[9] = v100 | v101;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 1024)
|
|
{
|
|
vertlist[10].setX(x + 1.0f);
|
|
vertlist[10].setY(y + 1.0f);
|
|
vertlist[10].setZ(z + 0.5f);
|
|
vertMaterials[10] = v110 | v111;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 2048)
|
|
{
|
|
vertlist[11].setX(x);
|
|
vertlist[11].setY(y + 1.0f);
|
|
vertlist[11].setZ(z + 0.5f);
|
|
vertMaterials[11] = v010 | v011;
|
|
}
|
|
|
|
for (int i=0;triTable[iCubeIndex][i]!=-1;i+=3)
|
|
{
|
|
//The three vertices forming a triangle
|
|
const Vector3DFloat vertex0 = vertlist[triTable[iCubeIndex][i ]] - offset;
|
|
const Vector3DFloat vertex1 = vertlist[triTable[iCubeIndex][i+1]] - offset;
|
|
const Vector3DFloat vertex2 = vertlist[triTable[iCubeIndex][i+2]] - offset;
|
|
|
|
//Cast to floats and divide by two.
|
|
//const Vector3DFloat vertex0AsFloat = (static_cast<Vector3DFloat>(vertex0) / 2.0f) - offset;
|
|
//const Vector3DFloat vertex1AsFloat = (static_cast<Vector3DFloat>(vertex1) / 2.0f) - offset;
|
|
//const Vector3DFloat vertex2AsFloat = (static_cast<Vector3DFloat>(vertex2) / 2.0f) - offset;
|
|
|
|
const uint8_t material0 = vertMaterials[triTable[iCubeIndex][i ]];
|
|
const uint8_t material1 = vertMaterials[triTable[iCubeIndex][i+1]];
|
|
const uint8_t material2 = vertMaterials[triTable[iCubeIndex][i+2]];
|
|
|
|
|
|
//If all the materials are the same, we just need one triangle for that material with all the alphas set high.
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1f,1.0f);
|
|
singleMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}//For each triangle
|
|
}//For each cell
|
|
|
|
//FIXME - can it happen that we have no vertices or triangles? Should exit early?
|
|
|
|
|
|
//for(std::map<uint8_t, IndexedSurfacePatch*>::iterator iterPatch = surfacePatchMapResult.begin(); iterPatch != surfacePatchMapResult.end(); ++iterPatch)
|
|
{
|
|
|
|
std::vector<SurfaceVertex>::iterator iterSurfaceVertex = singleMaterialPatch->getVertices().begin();
|
|
while(iterSurfaceVertex != singleMaterialPatch->getVertices().end())
|
|
{
|
|
Vector3DFloat tempNormal = computeNormal(volumeData, static_cast<Vector3DFloat>(iterSurfaceVertex->getPosition() + offset), CENTRAL_DIFFERENCE);
|
|
const_cast<SurfaceVertex&>(*iterSurfaceVertex).setNormal(tempNormal);
|
|
++iterSurfaceVertex;
|
|
}
|
|
}
|
|
}
|
|
|
|
Vector3DFloat computeNormal(BlockVolume<uint8_t>* volumeData, const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod)
|
|
{
|
|
const float posX = position.getX();
|
|
const float posY = position.getY();
|
|
const float posZ = position.getZ();
|
|
|
|
const uint16_t floorX = static_cast<uint16_t>(posX);
|
|
const uint16_t floorY = static_cast<uint16_t>(posY);
|
|
const uint16_t floorZ = static_cast<uint16_t>(posZ);
|
|
|
|
//Check all corners are within the volume, allowing a boundary for gradient estimation
|
|
bool lowerCornerInside = volumeData->containsPoint(Vector3DInt32(floorX, floorY, floorZ),1);
|
|
bool upperCornerInside = volumeData->containsPoint(Vector3DInt32(floorX+1, floorY+1, floorZ+1),1);
|
|
if((!lowerCornerInside) || (!upperCornerInside))
|
|
{
|
|
normalGenerationMethod = SIMPLE;
|
|
}
|
|
|
|
Vector3DFloat result;
|
|
|
|
BlockVolumeIterator<boost::uint8_t> volIter(*volumeData); //FIXME - save this somewhere - could be expensive to create?
|
|
|
|
|
|
if(normalGenerationMethod == SOBEL)
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
const Vector3DFloat gradFloor = computeSobelGradient(volIter);
|
|
if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX+1.0),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY+1.0),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ+1.0));
|
|
}
|
|
const Vector3DFloat gradCeil = computeSobelGradient(volIter);
|
|
result = ((gradFloor + gradCeil) * -1.0f);
|
|
if(result.lengthSquared() < 0.0001)
|
|
{
|
|
//Operation failed - fall back on simple gradient estimation
|
|
normalGenerationMethod = SIMPLE;
|
|
}
|
|
}
|
|
if(normalGenerationMethod == CENTRAL_DIFFERENCE)
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
const Vector3DFloat gradFloor = computeCentralDifferenceGradient(volIter);
|
|
if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX+1.0),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY+1.0),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ+1.0));
|
|
}
|
|
const Vector3DFloat gradCeil = computeCentralDifferenceGradient(volIter);
|
|
result = ((gradFloor + gradCeil) * -1.0f);
|
|
if(result.lengthSquared() < 0.0001)
|
|
{
|
|
//Operation failed - fall back on simple gradient estimation
|
|
normalGenerationMethod = SIMPLE;
|
|
}
|
|
}
|
|
if(normalGenerationMethod == SIMPLE)
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
const uint8_t uFloor = volIter.getVoxel() > 0 ? 1 : 0;
|
|
if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
uint8_t uCeil = volIter.peekVoxel1px0py0pz() > 0 ? 1 : 0;
|
|
result = Vector3DFloat(static_cast<float>(uFloor - uCeil),0.0,0.0);
|
|
}
|
|
else if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
uint8_t uCeil = volIter.peekVoxel0px1py0pz() > 0 ? 1 : 0;
|
|
result = Vector3DFloat(0.0,static_cast<float>(uFloor - uCeil),0.0);
|
|
}
|
|
else if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
uint8_t uCeil = volIter.peekVoxel0px0py1pz() > 0 ? 1 : 0;
|
|
result = Vector3DFloat(0.0, 0.0,static_cast<float>(uFloor - uCeil));
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
void generateSmoothMeshDataForRegion(BlockVolume<uint8_t>* volumeData, Region region, IndexedSurfacePatch* singleMaterialPatch)
|
|
{
|
|
//When generating the mesh for a region we actually look one voxel outside it in the
|
|
// back, bottom, right direction. Protect against access violations by cropping region here
|
|
Region regVolume = volumeData->getEnclosingRegion();
|
|
regVolume.setUpperCorner(regVolume.getUpperCorner() - Vector3DInt32(1,1,1));
|
|
region.cropTo(regVolume);
|
|
|
|
//Offset from lower block corner
|
|
const Vector3DFloat offset = static_cast<Vector3DFloat>(region.getLowerCorner());
|
|
|
|
Vector3DFloat vertlist[12];
|
|
uint8_t vertMaterials[12];
|
|
BlockVolumeIterator<boost::uint8_t> volIter(*volumeData);
|
|
volIter.setValidRegion(region);
|
|
|
|
const float threshold = 0.5f;
|
|
|
|
//////////////////////////////////////////////////////////////////////////
|
|
//Get mesh data
|
|
//////////////////////////////////////////////////////////////////////////
|
|
|
|
//Iterate over each cell in the region
|
|
for(volIter.setPosition(region.getLowerCorner().getX(),region.getLowerCorner().getY(), region.getLowerCorner().getZ());volIter.isValidForRegion();volIter.moveForwardInRegionXYZ())
|
|
{
|
|
//Current position
|
|
const uint16_t x = volIter.getPosX();
|
|
const uint16_t y = volIter.getPosY();
|
|
const uint16_t z = volIter.getPosZ();
|
|
|
|
//Voxels values
|
|
BlockVolumeIterator<boost::uint8_t> tempVolIter(*volumeData);
|
|
tempVolIter.setPosition(x,y,z);
|
|
const float v000 = tempVolIter.getAveragedVoxel(1);
|
|
tempVolIter.setPosition(x+1,y,z);
|
|
const float v100 = tempVolIter.getAveragedVoxel(1);
|
|
tempVolIter.setPosition(x,y+1,z);
|
|
const float v010 = tempVolIter.getAveragedVoxel(1);
|
|
tempVolIter.setPosition(x+1,y+1,z);
|
|
const float v110 = tempVolIter.getAveragedVoxel(1);
|
|
tempVolIter.setPosition(x,y,z+1);
|
|
const float v001 = tempVolIter.getAveragedVoxel(1);
|
|
tempVolIter.setPosition(x+1,y,z+1);
|
|
const float v101 = tempVolIter.getAveragedVoxel(1);
|
|
tempVolIter.setPosition(x,y+1,z+1);
|
|
const float v011 = tempVolIter.getAveragedVoxel(1);
|
|
tempVolIter.setPosition(x+1,y+1,z+1);
|
|
const float v111 = tempVolIter.getAveragedVoxel(1);
|
|
|
|
//Determine the index into the edge table which tells us which vertices are inside of the surface
|
|
uint8_t iCubeIndex = 0;
|
|
|
|
if (v000 < threshold) iCubeIndex |= 1;
|
|
if (v100 < threshold) iCubeIndex |= 2;
|
|
if (v110 < threshold) iCubeIndex |= 4;
|
|
if (v010 < threshold) iCubeIndex |= 8;
|
|
if (v001 < threshold) iCubeIndex |= 16;
|
|
if (v101 < threshold) iCubeIndex |= 32;
|
|
if (v111 < threshold) iCubeIndex |= 64;
|
|
if (v011 < threshold) iCubeIndex |= 128;
|
|
|
|
/* Cube is entirely in/out of the surface */
|
|
if (edgeTable[iCubeIndex] == 0)
|
|
{
|
|
continue;
|
|
}
|
|
|
|
/* Find the vertices where the surface intersects the cube */
|
|
if (edgeTable[iCubeIndex] & 1)
|
|
{
|
|
float a = v000;
|
|
float b = v100;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[0].setX(x + val);
|
|
vertlist[0].setY(y);
|
|
vertlist[0].setZ(z);
|
|
vertMaterials[0] = 1;//v000 | v100; //Because one of these is 0, the or operation takes the max.
|
|
}
|
|
if (edgeTable[iCubeIndex] & 2)
|
|
{
|
|
float a = v100;
|
|
float b = v110;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[1].setX(x + 1.0f);
|
|
vertlist[1].setY(y + val);
|
|
vertlist[1].setZ(z);
|
|
vertMaterials[1] = 1;//v100 | v110;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 4)
|
|
{
|
|
float a = v010;
|
|
float b = v110;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[2].setX(x + val);
|
|
vertlist[2].setY(y + 1.0f);
|
|
vertlist[2].setZ(z);
|
|
vertMaterials[2] = 1;//v010 | v110;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 8)
|
|
{
|
|
float a = v000;
|
|
float b = v010;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[3].setX(x);
|
|
vertlist[3].setY(y + val);
|
|
vertlist[3].setZ(z);
|
|
vertMaterials[3] = 1;//v000 | v010;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 16)
|
|
{
|
|
float a = v001;
|
|
float b = v101;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[4].setX(x + val);
|
|
vertlist[4].setY(y);
|
|
vertlist[4].setZ(z + 1.0f);
|
|
vertMaterials[4] = 1;//v001 | v101;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 32)
|
|
{
|
|
float a = v101;
|
|
float b = v111;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[5].setX(x + 1.0f);
|
|
vertlist[5].setY(y + val);
|
|
vertlist[5].setZ(z + 1.0f);
|
|
vertMaterials[5] = 1;//v101 | v111;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 64)
|
|
{
|
|
float a = v011;
|
|
float b = v111;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[6].setX(x + val);
|
|
vertlist[6].setY(y + 1.0f);
|
|
vertlist[6].setZ(z + 1.0f);
|
|
vertMaterials[6] = 1;//v011 | v111;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 128)
|
|
{
|
|
float a = v001;
|
|
float b = v011;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[7].setX(x);
|
|
vertlist[7].setY(y + val);
|
|
vertlist[7].setZ(z + 1.0f);
|
|
vertMaterials[7] = 1;//v001 | v011;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 256)
|
|
{
|
|
float a = v000;
|
|
float b = v001;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[8].setX(x);
|
|
vertlist[8].setY(y);
|
|
vertlist[8].setZ(z + val);
|
|
vertMaterials[8] = 1;//v000 | v001;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 512)
|
|
{
|
|
float a = v100;
|
|
float b = v101;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[9].setX(x + 1.0f);
|
|
vertlist[9].setY(y);
|
|
vertlist[9].setZ(z + val);
|
|
vertMaterials[9] = 1;//v100 | v101;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 1024)
|
|
{
|
|
float a = v110;
|
|
float b = v111;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[10].setX(x + 1.0f);
|
|
vertlist[10].setY(y + 1.0f);
|
|
vertlist[10].setZ(z + val);
|
|
vertMaterials[10] = 1;//v110 | v111;
|
|
}
|
|
if (edgeTable[iCubeIndex] & 2048)
|
|
{
|
|
float a = v010;
|
|
float b = v011;
|
|
float val = (threshold-a)/(b-a);
|
|
vertlist[11].setX(x);
|
|
vertlist[11].setY(y + 1.0f);
|
|
vertlist[11].setZ(z + val);
|
|
vertMaterials[11] = 1;//v010 | v011;
|
|
}
|
|
|
|
for (int i=0;triTable[iCubeIndex][i]!=-1;i+=3)
|
|
{
|
|
//The three vertices forming a triangle
|
|
const Vector3DFloat vertex0 = vertlist[triTable[iCubeIndex][i ]] - offset;
|
|
const Vector3DFloat vertex1 = vertlist[triTable[iCubeIndex][i+1]] - offset;
|
|
const Vector3DFloat vertex2 = vertlist[triTable[iCubeIndex][i+2]] - offset;
|
|
|
|
const uint8_t material0 = vertMaterials[triTable[iCubeIndex][i ]];
|
|
const uint8_t material1 = vertMaterials[triTable[iCubeIndex][i+1]];
|
|
const uint8_t material2 = vertMaterials[triTable[iCubeIndex][i+2]];
|
|
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1f,1.0f);
|
|
singleMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
|
|
}//For each triangle
|
|
}//For each cell
|
|
|
|
//FIXME - can it happen that we have no vertices or triangles? Should exit early?
|
|
|
|
|
|
//for(std::map<uint8_t, IndexedSurfacePatch*>::iterator iterPatch = surfacePatchMapResult.begin(); iterPatch != surfacePatchMapResult.end(); ++iterPatch)
|
|
{
|
|
|
|
std::vector<SurfaceVertex>::iterator iterSurfaceVertex = singleMaterialPatch->getVertices().begin();
|
|
while(iterSurfaceVertex != singleMaterialPatch->getVertices().end())
|
|
{
|
|
Vector3DFloat tempNormal = computeSmoothNormal(volumeData, static_cast<Vector3DFloat>(iterSurfaceVertex->getPosition() + offset), CENTRAL_DIFFERENCE);
|
|
const_cast<SurfaceVertex&>(*iterSurfaceVertex).setNormal(tempNormal);
|
|
++iterSurfaceVertex;
|
|
}
|
|
}
|
|
}
|
|
|
|
Vector3DFloat computeSmoothNormal(BlockVolume<uint8_t>* volumeData, const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod)
|
|
{
|
|
|
|
|
|
const float posX = position.getX();
|
|
const float posY = position.getY();
|
|
const float posZ = position.getZ();
|
|
|
|
const uint16_t floorX = static_cast<uint16_t>(posX);
|
|
const uint16_t floorY = static_cast<uint16_t>(posY);
|
|
const uint16_t floorZ = static_cast<uint16_t>(posZ);
|
|
|
|
//Check all corners are within the volume, allowing a boundary for gradient estimation
|
|
bool lowerCornerInside = volumeData->containsPoint(Vector3DInt32(floorX, floorY, floorZ),1);
|
|
bool upperCornerInside = volumeData->containsPoint(Vector3DInt32(floorX+1, floorY+1, floorZ+1),1);
|
|
if((!lowerCornerInside) || (!upperCornerInside))
|
|
{
|
|
normalGenerationMethod = SIMPLE;
|
|
}
|
|
|
|
Vector3DFloat result;
|
|
|
|
BlockVolumeIterator<boost::uint8_t> volIter(*volumeData); //FIXME - save this somewhere - could be expensive to create?
|
|
|
|
|
|
if(normalGenerationMethod == SOBEL)
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
const Vector3DFloat gradFloor = computeSobelGradient(volIter);
|
|
if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX+1.0),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY+1.0),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ+1.0));
|
|
}
|
|
const Vector3DFloat gradCeil = computeSobelGradient(volIter);
|
|
result = ((gradFloor + gradCeil) * -1.0f);
|
|
if(result.lengthSquared() < 0.0001)
|
|
{
|
|
//Operation failed - fall back on simple gradient estimation
|
|
normalGenerationMethod = SIMPLE;
|
|
}
|
|
}
|
|
if(normalGenerationMethod == CENTRAL_DIFFERENCE)
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
const Vector3DFloat gradFloor = computeSmoothCentralDifferenceGradient(volIter);
|
|
if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX+1.0),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY+1.0),static_cast<uint16_t>(posZ));
|
|
}
|
|
if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ+1.0));
|
|
}
|
|
const Vector3DFloat gradCeil = computeSmoothCentralDifferenceGradient(volIter);
|
|
result = ((gradFloor + gradCeil) * -1.0f);
|
|
if(result.lengthSquared() < 0.0001)
|
|
{
|
|
//Operation failed - fall back on simple gradient estimation
|
|
normalGenerationMethod = SIMPLE;
|
|
}
|
|
}
|
|
if(normalGenerationMethod == SIMPLE)
|
|
{
|
|
volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
|
|
const uint8_t uFloor = volIter.getVoxel() > 0 ? 1 : 0;
|
|
if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
uint8_t uCeil = volIter.peekVoxel1px0py0pz() > 0 ? 1 : 0;
|
|
result = Vector3DFloat(static_cast<float>(uFloor - uCeil),0.0,0.0);
|
|
}
|
|
else if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
uint8_t uCeil = volIter.peekVoxel0px1py0pz() > 0 ? 1 : 0;
|
|
result = Vector3DFloat(0.0,static_cast<float>(uFloor - uCeil),0.0);
|
|
}
|
|
else if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
|
|
{
|
|
uint8_t uCeil = volIter.peekVoxel0px0py1pz() > 0 ? 1 : 0;
|
|
result = Vector3DFloat(0.0, 0.0,static_cast<float>(uFloor - uCeil));
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
}
|