#pragma region License /****************************************************************************** This file is part of the PolyVox library Copyright (C) 2006 David Williams This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. ******************************************************************************/ #pragma endregion #include "PolyVoxCore/PolyVoxImpl/FastSurfaceExtractor.h" #include "PolyVoxCore/VolumeIterator.h" #include "PolyVoxCore/IndexedSurfacePatch.h" #include "PolyVoxCore/MarchingCubesTables.h" #include "PolyVoxCore/SurfaceVertex.h" namespace PolyVox { void extractFastSurfaceImpl(Volume* volumeData, Region region, IndexedSurfacePatch* singleMaterialPatch) { singleMaterialPatch->clear(); //For edge indices int32_t* vertexIndicesX0 = new int32_t[(region.width()+2) * (region.height()+2)]; int32_t* vertexIndicesY0 = new int32_t[(region.width()+2) * (region.height()+2)]; int32_t* vertexIndicesZ0 = new int32_t[(region.width()+2) * (region.height()+2)]; int32_t* vertexIndicesX1 = new int32_t[(region.width()+2) * (region.height()+2)]; int32_t* vertexIndicesY1 = new int32_t[(region.width()+2) * (region.height()+2)]; int32_t* vertexIndicesZ1 = new int32_t[(region.width()+2) * (region.height()+2)]; //Cell bitmasks uint8_t* bitmask0 = new uint8_t[(region.width()+2) * (region.height()+2)]; uint8_t* bitmask1 = new uint8_t[(region.width()+2) * (region.height()+2)]; //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 volume corner const Vector3DFloat offset = static_cast(region.getLowerCorner()); //Create a region corresponding to the first slice Region regSlice0(region); regSlice0.setUpperCorner(Vector3DInt32(regSlice0.getUpperCorner().getX(),regSlice0.getUpperCorner().getY(),regSlice0.getLowerCorner().getZ())); //Iterator to access the volume data VolumeIterator volIter(*volumeData); //Compute bitmask for initial slice uint32_t uNoOfNonEmptyCellsForSlice0 = computeInitialRoughBitmaskForSlice(volIter, regSlice0, offset, bitmask0); if(uNoOfNonEmptyCellsForSlice0 != 0) { //If there were some non-empty cells then generate initial slice vertices for them generateRoughVerticesForSlice(volIter,regSlice0, offset, bitmask0, singleMaterialPatch, vertexIndicesX0, vertexIndicesY0, vertexIndicesZ0); } for(uint32_t uSlice = 0; ((uSlice <= region.depth()-1) && (uSlice + offset.getZ() < region.getUpperCorner().getZ())); ++uSlice) { Region regSlice1(regSlice0); regSlice1.shift(Vector3DInt32(0,0,1)); uint32_t uNoOfNonEmptyCellsForSlice1 = computeRoughBitmaskForSliceFromPrevious(volIter, regSlice1, offset, bitmask1, bitmask0); if(uNoOfNonEmptyCellsForSlice1 != 0) { generateRoughVerticesForSlice(volIter,regSlice1, offset, bitmask1, singleMaterialPatch, vertexIndicesX1, vertexIndicesY1, vertexIndicesZ1); } if((uNoOfNonEmptyCellsForSlice0 != 0) || (uNoOfNonEmptyCellsForSlice1 != 0)) { generateRoughIndicesForSlice(volIter, regSlice0, singleMaterialPatch, offset, bitmask0, bitmask1, vertexIndicesX0, vertexIndicesY0, vertexIndicesZ0, vertexIndicesX1, vertexIndicesY1, vertexIndicesZ1); } std::swap(uNoOfNonEmptyCellsForSlice0, uNoOfNonEmptyCellsForSlice1); std::swap(bitmask0, bitmask1); std::swap(vertexIndicesX0, vertexIndicesX1); std::swap(vertexIndicesY0, vertexIndicesY1); std::swap(vertexIndicesZ0, vertexIndicesZ1); regSlice0 = regSlice1; } delete[] bitmask0; delete[] bitmask1; delete[] vertexIndicesX0; delete[] vertexIndicesX1; delete[] vertexIndicesY0; delete[] vertexIndicesY1; delete[] vertexIndicesZ0; delete[] vertexIndicesZ1; } uint32_t getIndex(uint32_t x, uint32_t y, uint32_t regionWidth) { return x + (y * (regionWidth+1)); } uint32_t computeInitialRoughBitmaskForSlice(VolumeIterator& volIter, const Region& regSlice, const Vector3DFloat& offset, uint8_t* bitmask) { uint32_t uNoOfNonEmptyCells = 0; //Iterate over each cell in the region volIter.setPosition(regSlice.getLowerCorner().getX(),regSlice.getLowerCorner().getY(), regSlice.getLowerCorner().getZ()); volIter.setValidRegion(regSlice); do { //Current position const uint16_t x = volIter.getPosX() - offset.getX(); const uint16_t y = volIter.getPosY() - offset.getY(); //Determine the index into the edge table which tells us which vertices are inside of the surface uint8_t iCubeIndex = 0; if((x==0) && (y==0)) { 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(); 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; } else if((x>0) && y==0) { const uint8_t v100 = volIter.peekVoxel1px0py0pz(); const uint8_t v110 = volIter.peekVoxel1px1py0pz(); const uint8_t v101 = volIter.peekVoxel1px0py1pz(); const uint8_t v111 = volIter.peekVoxel1px1py1pz(); //x uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y, regSlice.width()+1)]; uint8_t srcBit6 = iPreviousCubeIndexX & 64; uint8_t destBit7 = srcBit6 << 1; uint8_t srcBit5 = iPreviousCubeIndexX & 32; uint8_t destBit4 = srcBit5 >> 1; uint8_t srcBit2 = iPreviousCubeIndexX & 4; uint8_t destBit3 = srcBit2 << 1; uint8_t srcBit1 = iPreviousCubeIndexX & 2; uint8_t destBit0 = srcBit1 >> 1; iCubeIndex |= destBit0; if (v100 == 0) iCubeIndex |= 2; if (v110 == 0) iCubeIndex |= 4; iCubeIndex |= destBit3; iCubeIndex |= destBit4; if (v101 == 0) iCubeIndex |= 32; if (v111 == 0) iCubeIndex |= 64; iCubeIndex |= destBit7; } else if((x==0) && (y>0)) { const uint8_t v010 = volIter.peekVoxel0px1py0pz(); const uint8_t v110 = volIter.peekVoxel1px1py0pz(); const uint8_t v011 = volIter.peekVoxel0px1py1pz(); const uint8_t v111 = volIter.peekVoxel1px1py1pz(); //y uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1, regSlice.width()+1)]; uint8_t srcBit7 = iPreviousCubeIndexY & 128; uint8_t destBit4 = srcBit7 >> 3; uint8_t srcBit6 = iPreviousCubeIndexY & 64; uint8_t destBit5 = srcBit6 >> 1; uint8_t srcBit3 = iPreviousCubeIndexY & 8; uint8_t destBit0 = srcBit3 >> 3; uint8_t srcBit2 = iPreviousCubeIndexY & 4; uint8_t destBit1 = srcBit2 >> 1; iCubeIndex |= destBit0; iCubeIndex |= destBit1; if (v110 == 0) iCubeIndex |= 4; if (v010 == 0) iCubeIndex |= 8; iCubeIndex |= destBit4; iCubeIndex |= destBit5; if (v111 == 0) iCubeIndex |= 64; if (v011 == 0) iCubeIndex |= 128; } else { const uint8_t v110 = volIter.peekVoxel1px1py0pz(); const uint8_t v111 = volIter.peekVoxel1px1py1pz(); //y uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1, regSlice.width()+1)]; uint8_t srcBit7 = iPreviousCubeIndexY & 128; uint8_t destBit4 = srcBit7 >> 3; uint8_t srcBit6 = iPreviousCubeIndexY & 64; uint8_t destBit5 = srcBit6 >> 1; uint8_t srcBit3 = iPreviousCubeIndexY & 8; uint8_t destBit0 = srcBit3 >> 3; uint8_t srcBit2 = iPreviousCubeIndexY & 4; uint8_t destBit1 = srcBit2 >> 1; //x uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y, regSlice.width()+1)]; srcBit6 = iPreviousCubeIndexX & 64; uint8_t destBit7 = srcBit6 << 1; srcBit2 = iPreviousCubeIndexX & 4; uint8_t destBit3 = srcBit2 << 1; iCubeIndex |= destBit0; iCubeIndex |= destBit1; if (v110 == 0) iCubeIndex |= 4; iCubeIndex |= destBit3; iCubeIndex |= destBit4; iCubeIndex |= destBit5; if (v111 == 0) iCubeIndex |= 64; iCubeIndex |= destBit7; } //Save the bitmask bitmask[getIndex(x,y, regSlice.width()+1)] = iCubeIndex; if(edgeTable[iCubeIndex] != 0) { ++uNoOfNonEmptyCells; } }while(volIter.moveForwardInRegionXYZ());//For each cell return uNoOfNonEmptyCells; } uint32_t computeRoughBitmaskForSliceFromPrevious(VolumeIterator& volIter, const Region& regSlice, const Vector3DFloat& offset, uint8_t* bitmask, uint8_t* previousBitmask) { uint32_t uNoOfNonEmptyCells = 0; //Iterate over each cell in the region volIter.setPosition(regSlice.getLowerCorner().getX(),regSlice.getLowerCorner().getY(), regSlice.getLowerCorner().getZ()); volIter.setValidRegion(regSlice); do { //Current position const uint16_t x = volIter.getPosX() - offset.getX(); const uint16_t y = volIter.getPosY() - offset.getY(); //Determine the index into the edge table which tells us which vertices are inside of the surface uint8_t iCubeIndex = 0; if((x==0) && (y==0)) { const uint8_t v001 = volIter.peekVoxel0px0py1pz(); const uint8_t v101 = volIter.peekVoxel1px0py1pz(); const uint8_t v011 = volIter.peekVoxel0px1py1pz(); const uint8_t v111 = volIter.peekVoxel1px1py1pz(); //z uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y, regSlice.width()+1)]; iCubeIndex = iPreviousCubeIndexZ >> 4; if (v001 == 0) iCubeIndex |= 16; if (v101 == 0) iCubeIndex |= 32; if (v111 == 0) iCubeIndex |= 64; if (v011 == 0) iCubeIndex |= 128; } else if((x>0) && y==0) { const uint8_t v101 = volIter.peekVoxel1px0py1pz(); const uint8_t v111 = volIter.peekVoxel1px1py1pz(); //z uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y, regSlice.width()+1)]; iCubeIndex = iPreviousCubeIndexZ >> 4; //x uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y, regSlice.width()+1)]; uint8_t srcBit6 = iPreviousCubeIndexX & 64; uint8_t destBit7 = srcBit6 << 1; uint8_t srcBit5 = iPreviousCubeIndexX & 32; uint8_t destBit4 = srcBit5 >> 1; iCubeIndex |= destBit4; if (v101 == 0) iCubeIndex |= 32; if (v111 == 0) iCubeIndex |= 64; iCubeIndex |= destBit7; } else if((x==0) && (y>0)) { const uint8_t v011 = volIter.peekVoxel0px1py1pz(); const uint8_t v111 = volIter.peekVoxel1px1py1pz(); //z uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y, regSlice.width()+1)]; iCubeIndex = iPreviousCubeIndexZ >> 4; //y uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1, regSlice.width()+1)]; uint8_t srcBit7 = iPreviousCubeIndexY & 128; uint8_t destBit4 = srcBit7 >> 3; uint8_t srcBit6 = iPreviousCubeIndexY & 64; uint8_t destBit5 = srcBit6 >> 1; iCubeIndex |= destBit4; iCubeIndex |= destBit5; if (v111 == 0) iCubeIndex |= 64; if (v011 == 0) iCubeIndex |= 128; } else { const uint8_t v111 = volIter.peekVoxel1px1py1pz(); //z uint8_t iPreviousCubeIndexZ = previousBitmask[getIndex(x,y, regSlice.width()+1)]; iCubeIndex = iPreviousCubeIndexZ >> 4; //y uint8_t iPreviousCubeIndexY = bitmask[getIndex(x,y-1, regSlice.width()+1)]; uint8_t srcBit7 = iPreviousCubeIndexY & 128; uint8_t destBit4 = srcBit7 >> 3; uint8_t srcBit6 = iPreviousCubeIndexY & 64; uint8_t destBit5 = srcBit6 >> 1; //x uint8_t iPreviousCubeIndexX = bitmask[getIndex(x-1,y, regSlice.width()+1)]; srcBit6 = iPreviousCubeIndexX & 64; uint8_t destBit7 = srcBit6 << 1; iCubeIndex |= destBit4; iCubeIndex |= destBit5; if (v111 == 0) iCubeIndex |= 64; iCubeIndex |= destBit7; } //Save the bitmask bitmask[getIndex(x,y, regSlice.width()+1)] = iCubeIndex; if(edgeTable[iCubeIndex] != 0) { ++uNoOfNonEmptyCells; } }while(volIter.moveForwardInRegionXYZ());//For each cell return uNoOfNonEmptyCells; } void generateRoughVerticesForSlice(VolumeIterator& volIter, Region& regSlice, const Vector3DFloat& offset, uint8_t* bitmask, IndexedSurfacePatch* singleMaterialPatch,int32_t vertexIndicesX[],int32_t vertexIndicesY[],int32_t vertexIndicesZ[]) { //Iterate over each cell in the region volIter.setPosition(regSlice.getLowerCorner().getX(),regSlice.getLowerCorner().getY(), regSlice.getLowerCorner().getZ()); volIter.setValidRegion(regSlice); //while(volIter.moveForwardInRegionXYZ()) 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(); const uint8_t v000 = volIter.getVoxel(); //Determine the index into the edge table which tells us which vertices are inside of the surface uint8_t iCubeIndex = bitmask[getIndex(x,y, regSlice.width()+1)]; /* 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()) { const uint8_t v100 = volIter.peekVoxel1px0py0pz(); const Vector3DFloat v3dPosition(x + 0.5f, y, z); const Vector3DFloat v3dNormal(v000 > v100 ? 1.0f : -1.0f, 0.0f, 0.0f); const uint8_t uMaterial = v000 | v100; //Because one of these is 0, the or operation takes the max. const SurfaceVertex surfaceVertex(v3dPosition, v3dNormal, uMaterial); uint32_t uLastVertexIndex = singleMaterialPatch->addVertex(surfaceVertex); vertexIndicesX[getIndex(x,y, regSlice.width()+1)] = uLastVertexIndex; } } if (edgeTable[iCubeIndex] & 8) { if((y + offset.getY()) != regSlice.getUpperCorner().getY()) { const uint8_t v010 = volIter.peekVoxel0px1py0pz(); const Vector3DFloat v3dPosition(x, y + 0.5f, z); const Vector3DFloat v3dNormal(0.0f, v000 > v010 ? 1.0f : -1.0f, 0.0f); const uint8_t uMaterial = v000 | v010; SurfaceVertex surfaceVertex(v3dPosition, v3dNormal, uMaterial); uint32_t uLastVertexIndex = singleMaterialPatch->addVertex(surfaceVertex); vertexIndicesY[getIndex(x,y, regSlice.width()+1)] = uLastVertexIndex; } } if (edgeTable[iCubeIndex] & 256) { //if((z + offset.getZ()) != upperCorner.getZ()) { const uint8_t v001 = volIter.peekVoxel0px0py1pz(); const Vector3DFloat v3dPosition(x, y, z + 0.5f); const Vector3DFloat v3dNormal(0.0f, 0.0f, v000 > v001 ? 1.0f : -1.0f); const uint8_t uMaterial = v000 | v001; SurfaceVertex surfaceVertex(v3dPosition, v3dNormal, uMaterial); uint32_t uLastVertexIndex = singleMaterialPatch->addVertex(surfaceVertex); vertexIndicesZ[getIndex(x,y, regSlice.width()+1)] = uLastVertexIndex; } } }while(volIter.moveForwardInRegionXYZ());//For each cell } void generateRoughIndicesForSlice(VolumeIterator& volIter, const Region& regSlice, IndexedSurfacePatch* singleMaterialPatch, const Vector3DFloat& offset, uint8_t* bitmask0, uint8_t* bitmask1, int32_t vertexIndicesX0[],int32_t vertexIndicesY0[],int32_t vertexIndicesZ0[], int32_t vertexIndicesX1[],int32_t vertexIndicesY1[],int32_t vertexIndicesZ1[]) { 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, regSlice.width()+1)]; /* 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, regSlice.width()+1)]; assert(indlist[0] != -1); } if (edgeTable[iCubeIndex] & 2) { indlist[1] = vertexIndicesY0[getIndex(x+1,y, regSlice.width()+1)]; assert(indlist[1] != -1); } if (edgeTable[iCubeIndex] & 4) { indlist[2] = vertexIndicesX0[getIndex(x,y+1, regSlice.width()+1)]; assert(indlist[2] != -1); } if (edgeTable[iCubeIndex] & 8) { indlist[3] = vertexIndicesY0[getIndex(x,y, regSlice.width()+1)]; assert(indlist[3] != -1); } if (edgeTable[iCubeIndex] & 16) { indlist[4] = vertexIndicesX1[getIndex(x,y, regSlice.width()+1)]; assert(indlist[4] != -1); } if (edgeTable[iCubeIndex] & 32) { indlist[5] = vertexIndicesY1[getIndex(x+1,y, regSlice.width()+1)]; assert(indlist[5] != -1); } if (edgeTable[iCubeIndex] & 64) { indlist[6] = vertexIndicesX1[getIndex(x,y+1, regSlice.width()+1)]; assert(indlist[6] != -1); } if (edgeTable[iCubeIndex] & 128) { indlist[7] = vertexIndicesY1[getIndex(x,y, regSlice.width()+1)]; assert(indlist[7] != -1); } if (edgeTable[iCubeIndex] & 256) { indlist[8] = vertexIndicesZ0[getIndex(x,y, regSlice.width()+1)]; assert(indlist[8] != -1); } if (edgeTable[iCubeIndex] & 512) { indlist[9] = vertexIndicesZ0[getIndex(x+1,y, regSlice.width()+1)]; assert(indlist[9] != -1); } if (edgeTable[iCubeIndex] & 1024) { indlist[10] = vertexIndicesZ0[getIndex(x+1,y+1, regSlice.width()+1)]; assert(indlist[10] != -1); } if (edgeTable[iCubeIndex] & 2048) { indlist[11] = vertexIndicesZ0[getIndex(x,y+1, regSlice.width()+1)]; assert(indlist[11] != -1); } for (int i=0;triTable[iCubeIndex][i]!=-1;i+=3) { uint32_t ind0 = indlist[triTable[iCubeIndex][i ]]; uint32_t ind1 = indlist[triTable[iCubeIndex][i+1]]; uint32_t ind2 = indlist[triTable[iCubeIndex][i+2]]; singleMaterialPatch->addTriangle(ind0, ind1, ind2); }//For each triangle }while(volIter.moveForwardInRegionXYZ());//For each cell } }