803 lines
31 KiB
C++
803 lines
31 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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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_patchMultiMaterial = new IndexedSurfacePatch(true);
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regionGeometry.m_v3dRegionPosition = iterChangedRegions->getLowerCorner();
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generateRoughMeshDataForRegion(volume.getVolumeData(), *iterChangedRegions, regionGeometry.m_patchSingleMaterial, regionGeometry.m_patchMultiMaterial);
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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_bContainsMultiMaterialPatch = regionGeometry.m_patchMultiMaterial->getVertices().size() > 0;
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regionGeometry.m_bIsEmpty = ((regionGeometry.m_patchSingleMaterial->getVertices().size() == 0) && (regionGeometry.m_patchMultiMaterial->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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void genMultiFromSingle(IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch)
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{
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std::vector<SurfaceVertex>& vertices = singleMaterialPatch->m_vecVertices;
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std::vector<boost::uint32_t>& indices = singleMaterialPatch->m_vecTriangleIndices;
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if(vertices.size() == 0)
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{
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return;
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}
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for(boost::uint32_t ct = 0; ct < indices.size()-2; ct+=3)
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{
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if((vertices[indices[ct]].getMaterial() != vertices[indices[ct+1]].getMaterial()) || (vertices[indices[ct]].getMaterial() != vertices[indices[ct+2]].getMaterial()))
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{
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SurfaceVertex vert0 = vertices[indices[ct+0]];
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SurfaceVertex vert1 = vertices[indices[ct+1]];
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SurfaceVertex vert2 = vertices[indices[ct+2]];
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float mat0 = vert0.getMaterial();
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float mat1 = vert1.getMaterial();
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float mat2 = vert2.getMaterial();
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if((mat0 == mat1) && (mat1 == mat2))
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{
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exit(1);
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}
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vert0.setMaterial(mat0); vert0.setAlpha(1.0);
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vert1.setMaterial(mat0); vert1.setAlpha(0.0);
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vert2.setMaterial(mat0); vert2.setAlpha(0.0);
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multiMaterialPatch->addTriangle(vert0, vert1, vert2);
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vert0.setMaterial(mat1); vert0.setAlpha(0.0);
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vert1.setMaterial(mat1); vert1.setAlpha(1.0);
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vert2.setMaterial(mat1); vert2.setAlpha(0.0);
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multiMaterialPatch->addTriangle(vert0, vert1, vert2);
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vert0.setMaterial(mat2); vert0.setAlpha(0.0);
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vert1.setMaterial(mat2); vert1.setAlpha(0.0);
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vert2.setMaterial(mat2); vert2.setAlpha(1.0);
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multiMaterialPatch->addTriangle(vert0, vert1, vert2);
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/*vert0.setMaterial(vertices[indices[ct+1]].getMaterial()); vert0.setAlpha(0.0);
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vert1.setMaterial(vertices[indices[ct+1]].getMaterial()); vert1.setAlpha(1.0);
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vert2.setMaterial(vertices[indices[ct+1]].getMaterial()); vert2.setAlpha(0.0);
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multiMaterialPatch->addTriangle(vert0, vert1, vert2);*/
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/*vert0.setMaterial(vertices[indices[ct+2]].getMaterial()); vert0.setAlpha(0.0);
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vert1.setMaterial(vertices[indices[ct+2]].getMaterial()); vert1.setAlpha(1.0);
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vert2.setMaterial(vertices[indices[ct+2]].getMaterial()); vert2.setAlpha(0.0);
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multiMaterialPatch->addTriangle(vert0, vert1, vert2);*/
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//multiMaterialPatch->addTriangle(vert0Alpha0, vert1Alpha1, vert2Alpha0);
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//multiMaterialPatch->addTriangle(vert0Alpha0, vert1Alpha0, vert2Alpha1);
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/*SurfaceVertex v0 = vertices[indices[ct+0]]; v0.setMaterial(2.1); v0.setAlpha(1.0);
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SurfaceVertex v1 = vertices[indices[ct+1]]; v1.setMaterial(2.1); v1.setAlpha(1.0);
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SurfaceVertex v2 = vertices[indices[ct+2]]; v2.setMaterial(2.1); v2.setAlpha(1.0);
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multiMaterialPatch->addTriangle(v0,v1,v2);*/
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}
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}
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}
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void generateRoughMeshDataForRegion(BlockVolume<uint8_t>* volumeData, Region region, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch)
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{
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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 lower block corner
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const Vector3DFloat offset = static_cast<Vector3DFloat>(region.getLowerCorner());
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Vector3DFloat vertlist[12];
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uint8_t vertMaterials[12];
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BlockVolumeIterator<boost::uint8_t> volIter(*volumeData);
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volIter.setValidRegion(region);
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//////////////////////////////////////////////////////////////////////////
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//Get mesh data
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//////////////////////////////////////////////////////////////////////////
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//Iterate over each cell in the region
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for(volIter.setPosition(region.getLowerCorner().getX(),region.getLowerCorner().getY(), region.getLowerCorner().getZ());volIter.isValidForRegion();volIter.moveForwardInRegion())
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{
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//Current position
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const uint16_t x = volIter.getPosX();
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const uint16_t y = volIter.getPosY();
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const uint16_t z = volIter.getPosZ();
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//Voxels values
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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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//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 (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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/* Cube is entirely in/out of the surface */
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if (edgeTable[iCubeIndex] == 0)
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{
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continue;
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}
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/* Find the vertices where the surface intersects the cube */
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if (edgeTable[iCubeIndex] & 1)
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{
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vertlist[0].setX(x + 0.5f);
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vertlist[0].setY(y);
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vertlist[0].setZ(z);
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vertMaterials[0] = v000 | v100; //Because one of these is 0, the or operation takes the max.
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}
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if (edgeTable[iCubeIndex] & 2)
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{
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vertlist[1].setX(x + 1.0f);
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vertlist[1].setY(y + 0.5f);
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vertlist[1].setZ(z);
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vertMaterials[1] = v100 | v110;
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}
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if (edgeTable[iCubeIndex] & 4)
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{
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vertlist[2].setX(x + 0.5f);
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vertlist[2].setY(y + 1.0f);
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vertlist[2].setZ(z);
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vertMaterials[2] = v010 | v110;
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}
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if (edgeTable[iCubeIndex] & 8)
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{
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vertlist[3].setX(x);
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vertlist[3].setY(y + 0.5f);
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vertlist[3].setZ(z);
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vertMaterials[3] = v000 | v010;
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}
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if (edgeTable[iCubeIndex] & 16)
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{
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vertlist[4].setX(x + 0.5f);
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vertlist[4].setY(y);
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vertlist[4].setZ(z + 1.0f);
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vertMaterials[4] = v001 | v101;
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}
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if (edgeTable[iCubeIndex] & 32)
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{
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vertlist[5].setX(x + 1.0f);
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vertlist[5].setY(y + 0.5f);
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vertlist[5].setZ(z + 1.0f);
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vertMaterials[5] = v101 | v111;
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}
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if (edgeTable[iCubeIndex] & 64)
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{
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vertlist[6].setX(x + 0.5f);
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vertlist[6].setY(y + 1.0f);
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vertlist[6].setZ(z + 1.0f);
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vertMaterials[6] = v011 | v111;
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}
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if (edgeTable[iCubeIndex] & 128)
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{
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vertlist[7].setX(x);
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vertlist[7].setY(y + 0.5f);
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vertlist[7].setZ(z + 1.0f);
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vertMaterials[7] = v001 | v011;
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}
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if (edgeTable[iCubeIndex] & 256)
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{
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vertlist[8].setX(x);
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vertlist[8].setY(y);
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vertlist[8].setZ(z + 0.5f);
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vertMaterials[8] = v000 | v001;
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}
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if (edgeTable[iCubeIndex] & 512)
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{
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vertlist[9].setX(x + 1.0f);
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vertlist[9].setY(y);
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vertlist[9].setZ(z + 0.5f);
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vertMaterials[9] = v100 | v101;
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}
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if (edgeTable[iCubeIndex] & 1024)
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{
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vertlist[10].setX(x + 1.0f);
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vertlist[10].setY(y + 1.0f);
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vertlist[10].setZ(z + 0.5f);
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vertMaterials[10] = v110 | v111;
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}
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if (edgeTable[iCubeIndex] & 2048)
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{
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vertlist[11].setX(x);
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vertlist[11].setY(y + 1.0f);
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vertlist[11].setZ(z + 0.5f);
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vertMaterials[11] = v010 | v011;
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}
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for (int i=0;triTable[iCubeIndex][i]!=-1;i+=3)
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{
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//The three vertices forming a triangle
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const Vector3DFloat vertex0 = vertlist[triTable[iCubeIndex][i ]] - offset;
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const Vector3DFloat vertex1 = vertlist[triTable[iCubeIndex][i+1]] - offset;
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const Vector3DFloat vertex2 = vertlist[triTable[iCubeIndex][i+2]] - offset;
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//Cast to floats and divide by two.
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//const Vector3DFloat vertex0AsFloat = (static_cast<Vector3DFloat>(vertex0) / 2.0f) - offset;
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//const Vector3DFloat vertex1AsFloat = (static_cast<Vector3DFloat>(vertex1) / 2.0f) - offset;
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//const Vector3DFloat vertex2AsFloat = (static_cast<Vector3DFloat>(vertex2) / 2.0f) - offset;
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const uint8_t material0 = vertMaterials[triTable[iCubeIndex][i ]];
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const uint8_t material1 = vertMaterials[triTable[iCubeIndex][i+1]];
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const uint8_t material2 = vertMaterials[triTable[iCubeIndex][i+2]];
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//If all the materials are the same, we just need one triangle for that material with all the alphas set high.
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SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
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SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
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SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1f,1.0f);
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singleMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
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}//For each triangle
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}//For each cell
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//FIXME - can it happen that we have no vertices or triangles? Should exit early?
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//for(std::map<uint8_t, IndexedSurfacePatch*>::iterator iterPatch = surfacePatchMapResult.begin(); iterPatch != surfacePatchMapResult.end(); ++iterPatch)
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{
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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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iterSurfaceVertex = multiMaterialPatch->getVertices().begin();
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while(iterSurfaceVertex != multiMaterialPatch->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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uint16_t noOfRemovedVertices = 0;
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//do
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{
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//noOfRemovedVertices = iterPatch->second.decimate();
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}
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//while(noOfRemovedVertices > 10); //We don't worry about the last few vertices - it's not worth the overhead of calling the function.
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}
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//return singleMaterialPatch;
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}
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Vector3DFloat computeNormal(BlockVolume<uint8_t>* volumeData, const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod)
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{
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const float posX = position.getX();
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const float posY = position.getY();
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const float posZ = position.getZ();
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const uint16_t floorX = static_cast<uint16_t>(posX);
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const uint16_t floorY = static_cast<uint16_t>(posY);
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const uint16_t floorZ = static_cast<uint16_t>(posZ);
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//Check all corners are within the volume, allowing a boundary for gradient estimation
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bool lowerCornerInside = volumeData->containsPoint(Vector3DInt32(floorX, floorY, floorZ),1);
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bool upperCornerInside = volumeData->containsPoint(Vector3DInt32(floorX+1, floorY+1, floorZ+1),1);
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if((!lowerCornerInside) || (!upperCornerInside))
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{
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normalGenerationMethod = SIMPLE;
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}
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Vector3DFloat result;
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BlockVolumeIterator<boost::uint8_t> volIter(*volumeData); //FIXME - save this somewhere - could be expensive to create?
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if(normalGenerationMethod == SOBEL)
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{
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volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
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const Vector3DFloat gradFloor = computeSobelGradient(volIter);
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if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
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{
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volIter.setPosition(static_cast<uint16_t>(posX+1.0),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
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}
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if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
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{
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volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY+1.0),static_cast<uint16_t>(posZ));
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}
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if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
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{
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volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ+1.0));
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}
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const Vector3DFloat gradCeil = computeSobelGradient(volIter);
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result = ((gradFloor + gradCeil) * -1.0f);
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if(result.lengthSquared() < 0.0001)
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{
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//Operation failed - fall back on simple gradient estimation
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normalGenerationMethod = SIMPLE;
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}
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}
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if(normalGenerationMethod == CENTRAL_DIFFERENCE)
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{
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volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
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const Vector3DFloat gradFloor = computeCentralDifferenceGradient(volIter);
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if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
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{
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volIter.setPosition(static_cast<uint16_t>(posX+1.0),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
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}
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if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
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{
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volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY+1.0),static_cast<uint16_t>(posZ));
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}
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if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
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{
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volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ+1.0));
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}
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const Vector3DFloat gradCeil = computeCentralDifferenceGradient(volIter);
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result = ((gradFloor + gradCeil) * -1.0f);
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if(result.lengthSquared() < 0.0001)
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{
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//Operation failed - fall back on simple gradient estimation
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normalGenerationMethod = SIMPLE;
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}
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}
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if(normalGenerationMethod == SIMPLE)
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{
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volIter.setPosition(static_cast<uint16_t>(posX),static_cast<uint16_t>(posY),static_cast<uint16_t>(posZ));
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const uint8_t uFloor = volIter.getVoxel() > 0 ? 1 : 0;
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if((posX - floorX) > 0.25) //The result should be 0.0 or 0.5
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{
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uint8_t uCeil = volIter.peekVoxel1px0py0pz() > 0 ? 1 : 0;
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result = Vector3DFloat(static_cast<float>(uFloor - uCeil),0.0,0.0);
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}
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else if((posY - floorY) > 0.25) //The result should be 0.0 or 0.5
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{
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uint8_t uCeil = volIter.peekVoxel0px1py0pz() > 0 ? 1 : 0;
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result = Vector3DFloat(0.0,static_cast<float>(uFloor - uCeil),0.0);
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}
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else if((posZ - floorZ) > 0.25) //The result should be 0.0 or 0.5
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{
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uint8_t uCeil = volIter.peekVoxel0px0py1pz() > 0 ? 1 : 0;
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result = Vector3DFloat(0.0, 0.0,static_cast<float>(uFloor - uCeil));
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}
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}
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return result;
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}
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void generateSmoothMeshDataForRegion(BlockVolume<uint8_t>* volumeData, Region region, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch)
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{
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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);
|
|
|
|
//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.moveForwardInRegion())
|
|
{
|
|
//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]];
|
|
|
|
//If all the materials are the same, we just need one triangle for that material with all the alphas set high.
|
|
/*if((material0 == material1) && (material1 == material2))
|
|
{*/
|
|
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);
|
|
/*}
|
|
else if(material0 == material1)
|
|
{
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1,0.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material2 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material2 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1,1.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
}
|
|
else if(material0 == material2)
|
|
{
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1,1.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1,0.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
}
|
|
else if(material1 == material2)
|
|
{
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1,1.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1,0.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1,0.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1,1.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1,0.0);
|
|
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
|
|
}
|
|
|
|
{
|
|
SurfaceVertex surfaceVertex0Alpha1(vertex0,material2 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex1Alpha1(vertex1,material2 + 0.1,0.0);
|
|
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1,1.0);
|
|
multiMaterialPatch->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;
|
|
}
|
|
|
|
iterSurfaceVertex = multiMaterialPatch->getVertices().begin();
|
|
while(iterSurfaceVertex != multiMaterialPatch->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;
|
|
}
|
|
}
|