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Moved some code from PolyVoxSceneManager to SurfaceExtractors

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This commit is contained in:
David Williams 2008-05-24 17:29:27 +00:00
parent b42f28793f
commit 0b012cbd75
8 changed files with 903 additions and 820 deletions
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5
CMakeLists.txt
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@ -5,7 +5,8 @@ SET(SRC_FILES
source/IndexedSurfacePatch.cpp
source/MarchingCubesTables.cpp
source/PolyVoxSceneManager.cpp
source/RegionGeometry.cpp
source/RegionGeometry.cpp
source/SurfaceExtractors.cpp
source/SurfaceVertex.cpp
source/Utility.cpp
)
@ -17,6 +18,7 @@ SET(INC_FILES
include/BlockVolume.h
include/BlockVolume.inl
include/Constants.h
include/Enums.h
include/GradientEstimators.h
include/GradientEstimators.inl
include/LinearVolume.h
@ -26,6 +28,7 @@ SET(INC_FILES
include/PolyVoxForwardDeclarations.h
include/PolyVoxSceneManager.h
include/RegionGeometry.h
include/SurfaceExtractors.h
include/SurfaceVertex.h
include/TypeDef.h
include/Utility.h

35
include/Enums.h Normal file
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@ -0,0 +1,35 @@
#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
#ifndef __PolyVox_Enums_H__
#define __PolyVox_Enums_H__
namespace PolyVox
{
enum NormalGenerationMethod
{
SIMPLE,
CENTRAL_DIFFERENCE,
SOBEL
};
}
#endif

1
include/GradientEstimators.h
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@ -26,7 +26,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
namespace PolyVox
{
//FIXME - gradient can be expressed with ints.
template <typename VoxelType>
Vector3DFloat computeCentralDifferenceGradient(const VolumeIterator<VoxelType>& volIter);

2
include/PolyVoxForwardDeclarations.h
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@ -22,6 +22,8 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#ifndef __PolyVox_ForwardDeclarations_H__
#define __PolyVox_ForwardDeclarations_H__
#include "Enums.h"
#include "boost/cstdint.hpp"
namespace PolyVox

15
include/PolyVoxSceneManager.h
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@ -32,13 +32,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
namespace PolyVox
{
enum NormalGenerationMethod
{
SIMPLE,
CENTRAL_DIFFERENCE,
SOBEL
};
/// Voxel scene manager
class POLYVOX_API PolyVoxSceneManager
{
@ -67,8 +60,8 @@ namespace PolyVox
//void generateLevelVolume(void);
void generateRoughMeshDataForRegion(boost::uint16_t regionX, boost::uint16_t regionY, boost::uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch) const;
void generateSmoothMeshDataForRegion(boost::uint16_t regionX, boost::uint16_t regionY, boost::uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch) const;
//bool containsPoint(Vector3DFloat pos, float boundary);
//bool containsPoint(Vector3DInt32 pos, boost::uint16_t boundary);
@ -76,8 +69,8 @@ namespace PolyVox
LinearVolume<bool>* volSurfaceUpToDate;
Vector3DFloat computeNormal(const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod) const;
Vector3DFloat computeSmoothNormal(const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod) const;
public:
void markVoxelChanged(boost::uint16_t x, boost::uint16_t y, boost::uint16_t z);

40
include/SurfaceExtractors.h Normal file
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@ -0,0 +1,40 @@
#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
#ifndef __PolyVox_SurfaceExtractors_H__
#define __PolyVox_SurfaceExtractors_H__
#pragma region Headers
#include "PolyVoxForwardDeclarations.h"
#include "boost/cstdint.hpp"
#pragma endregion
namespace PolyVox
{
void generateRoughMeshDataForRegion(BlockVolume<boost::uint8_t>* volumeData, boost::uint16_t regionX, boost::uint16_t regionY, boost::uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch);
Vector3DFloat computeNormal(BlockVolume<boost::uint8_t>* volumeData, const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod);
void generateSmoothMeshDataForRegion(BlockVolume<boost::uint8_t>* volumeData, boost::uint16_t regionX, boost::uint16_t regionY, boost::uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch);
Vector3DFloat computeSmoothNormal(BlockVolume<boost::uint8_t>* volumeData, const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod);
}
#endif

809
source/PolyVoxSceneManager.cpp
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@ -25,6 +25,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#include "MarchingCubesTables.h"
#include "PolyVoxSceneManager.h"
#include "RegionGeometry.h"
#include "SurfaceExtractors.h"
#include "SurfaceVertex.h"
#include "Utility.h"
#include "Vector.h"
@ -82,7 +83,7 @@ namespace PolyVox
regionGeometry.m_patchMultiMaterial = new IndexedSurfacePatch(true);
regionGeometry.m_v3dRegionPosition = Vector3DInt32(regionX, regionY, regionZ);
generateRoughMeshDataForRegion(regionX,regionY,regionZ, regionGeometry.m_patchSingleMaterial, regionGeometry.m_patchMultiMaterial);
generateRoughMeshDataForRegion(volumeData, regionX,regionY,regionZ, regionGeometry.m_patchSingleMaterial, regionGeometry.m_patchMultiMaterial);
regionGeometry.m_bContainsSingleMaterialPatch = regionGeometry.m_patchSingleMaterial->getVertices().size() > 0;
regionGeometry.m_bContainsMultiMaterialPatch = regionGeometry.m_patchMultiMaterial->getVertices().size() > 0;
@ -161,812 +162,6 @@ namespace PolyVox
markRegionChanged(firstX,firstY,firstZ,lastX,lastY,lastZ);
}
void PolyVoxSceneManager::generateRoughMeshDataForRegion(const uint16_t regionX, const uint16_t regionY, const uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch) const
{
//First and last voxels in the region
const uint16_t firstX = regionX * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstY = regionY * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstZ = regionZ * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t lastX = (std::min)(firstX + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastY = (std::min)(firstY + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastZ = (std::min)(firstZ + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
//Offset from lower block corner
const Vector3DFloat offset(firstX,firstY,firstZ);
Vector3DFloat vertlist[12];
uint8_t vertMaterials[12];
VolumeIterator<boost::uint8_t> volIter(*volumeData);
volIter.setValidRegion(firstX,firstY,firstZ,lastX,lastY,lastZ);
//////////////////////////////////////////////////////////////////////////
//Get mesh data
//////////////////////////////////////////////////////////////////////////
//Iterate over each cell in the region
for(volIter.setPosition(firstX,firstY,firstZ);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
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.
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 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
else if(material0 == material2)
{
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
else if(material1 == material2)
{
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
else
{
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
//If there not all the same, we need one triangle for each unique material.
//We'll also need some vertices with low alphas for blending.
/*else
{
SurfaceVertex surfaceVertex0Alpha0(vertex0,0.0);
SurfaceVertex surfaceVertex1Alpha0(vertex1,0.0);
SurfaceVertex surfaceVertex2Alpha0(vertex2,0.0);
if(material0 == material1)
{
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha0);
surfacePatchMapResult[material2]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha0, surfaceVertex2Alpha1);
}
else if(material1 == material2)
{
surfacePatchMapResult[material1]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha0, surfaceVertex2Alpha0);
}
else if(material2 == material0)
{
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha0, surfaceVertex2Alpha1);
surfacePatchMapResult[material1]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha1, surfaceVertex2Alpha0);
}
else
{
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha0, surfaceVertex2Alpha0);
surfacePatchMapResult[material1]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha1, surfaceVertex2Alpha0);
surfacePatchMapResult[material2]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha0, 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(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 = computeNormal(static_cast<Vector3DFloat>(iterSurfaceVertex->getPosition() + offset), CENTRAL_DIFFERENCE);
const_cast<SurfaceVertex&>(*iterSurfaceVertex).setNormal(tempNormal);
++iterSurfaceVertex;
}
uint16_t noOfRemovedVertices = 0;
//do
{
//noOfRemovedVertices = iterPatch->second.decimate();
}
//while(noOfRemovedVertices > 10); //We don't worry about the last few vertices - it's not worth the overhead of calling the function.
}
//return singleMaterialPatch;
}
void PolyVoxSceneManager::generateSmoothMeshDataForRegion(const uint16_t regionX, const uint16_t regionY, const uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch) const
{
//First and last voxels in the region
const uint16_t firstX = regionX * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstY = regionY * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstZ = regionZ * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t lastX = (std::min)(firstX + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastY = (std::min)(firstY + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastZ = (std::min)(firstZ + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
//Offset from lower block corner
const Vector3DFloat offset(firstX,firstY,firstZ);
Vector3DFloat vertlist[12];
uint8_t vertMaterials[12];
VolumeIterator<boost::uint8_t> volIter(*volumeData);
volIter.setValidRegion(firstX,firstY,firstZ,lastX,lastY,lastZ);
const float threshold = 0.5f;
//////////////////////////////////////////////////////////////////////////
//Get mesh data
//////////////////////////////////////////////////////////////////////////
//Iterate over each cell in the region
for(volIter.setPosition(firstX,firstY,firstZ);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
VolumeIterator<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(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(static_cast<Vector3DFloat>(iterSurfaceVertex->getPosition() + offset), CENTRAL_DIFFERENCE);
const_cast<SurfaceVertex&>(*iterSurfaceVertex).setNormal(tempNormal);
++iterSurfaceVertex;
}
}
}
Vector3DFloat PolyVoxSceneManager::computeNormal(const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod) const
{
const float posX = position.x();
const float posY = position.y();
const float posZ = position.z();
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;
VolumeIterator<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) * -1.0);
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) * -1.0);
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;
}
Vector3DFloat PolyVoxSceneManager::computeSmoothNormal(const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod) const
{
const float posX = position.x();
const float posY = position.y();
const float posZ = position.z();
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;
VolumeIterator<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) * -1.0);
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) * -1.0);
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 PolyVoxSceneManager::markVoxelChanged(uint16_t x, uint16_t y, uint16_t z)
{
//If we are not on a boundary, just mark one region.

816
source/SurfaceExtractors.cpp Normal file
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@ -0,0 +1,816 @@
#include "SurfaceExtractors.h"
#include "BlockVolume.h"
#include "GradientEstimators.h"
#include "IndexedSurfacePatch.h"
#include "MarchingCubesTables.h"
#include "VolumeIterator.h"
using namespace boost;
namespace PolyVox
{
void generateRoughMeshDataForRegion(BlockVolume<uint8_t>* volumeData, uint16_t regionX, uint16_t regionY, uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch)
{
//First and last voxels in the region
const uint16_t firstX = regionX * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstY = regionY * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstZ = regionZ * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t lastX = (std::min)(firstX + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastY = (std::min)(firstY + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastZ = (std::min)(firstZ + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
//Offset from lower block corner
const Vector3DFloat offset(firstX,firstY,firstZ);
Vector3DFloat vertlist[12];
uint8_t vertMaterials[12];
VolumeIterator<boost::uint8_t> volIter(*volumeData);
volIter.setValidRegion(firstX,firstY,firstZ,lastX,lastY,lastZ);
//////////////////////////////////////////////////////////////////////////
//Get mesh data
//////////////////////////////////////////////////////////////////////////
//Iterate over each cell in the region
for(volIter.setPosition(firstX,firstY,firstZ);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
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.
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 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
else if(material0 == material2)
{
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
else if(material1 == material2)
{
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
else
{
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material0 + 0.1f,1.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material0 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material0 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material1 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material1 + 0.1f,1.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material1 + 0.1f,0.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
{
SurfaceVertex surfaceVertex0Alpha1(vertex0,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex1Alpha1(vertex1,material2 + 0.1f,0.0f);
SurfaceVertex surfaceVertex2Alpha1(vertex2,material2 + 0.1f,1.0f);
multiMaterialPatch->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
}
}
//If there not all the same, we need one triangle for each unique material.
//We'll also need some vertices with low alphas for blending.
/*else
{
SurfaceVertex surfaceVertex0Alpha0(vertex0,0.0);
SurfaceVertex surfaceVertex1Alpha0(vertex1,0.0);
SurfaceVertex surfaceVertex2Alpha0(vertex2,0.0);
if(material0 == material1)
{
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha1, surfaceVertex2Alpha0);
surfacePatchMapResult[material2]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha0, surfaceVertex2Alpha1);
}
else if(material1 == material2)
{
surfacePatchMapResult[material1]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha1, surfaceVertex2Alpha1);
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha0, surfaceVertex2Alpha0);
}
else if(material2 == material0)
{
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha0, surfaceVertex2Alpha1);
surfacePatchMapResult[material1]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha1, surfaceVertex2Alpha0);
}
else
{
surfacePatchMapResult[material0]->addTriangle(surfaceVertex0Alpha1, surfaceVertex1Alpha0, surfaceVertex2Alpha0);
surfacePatchMapResult[material1]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha1, surfaceVertex2Alpha0);
surfacePatchMapResult[material2]->addTriangle(surfaceVertex0Alpha0, surfaceVertex1Alpha0, 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;
}
iterSurfaceVertex = multiMaterialPatch->getVertices().begin();
while(iterSurfaceVertex != multiMaterialPatch->getVertices().end())
{
Vector3DFloat tempNormal = computeNormal(volumeData, static_cast<Vector3DFloat>(iterSurfaceVertex->getPosition() + offset), CENTRAL_DIFFERENCE);
const_cast<SurfaceVertex&>(*iterSurfaceVertex).setNormal(tempNormal);
++iterSurfaceVertex;
}
uint16_t noOfRemovedVertices = 0;
//do
{
//noOfRemovedVertices = iterPatch->second.decimate();
}
//while(noOfRemovedVertices > 10); //We don't worry about the last few vertices - it's not worth the overhead of calling the function.
}
//return singleMaterialPatch;
}
Vector3DFloat computeNormal(BlockVolume<uint8_t>* volumeData, const Vector3DFloat& position, NormalGenerationMethod normalGenerationMethod)
{
const float posX = position.x();
const float posY = position.y();
const float posZ = position.z();
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;
VolumeIterator<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) * -1.0);
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) * -1.0);
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, uint16_t regionX, uint16_t regionY, uint16_t regionZ, IndexedSurfacePatch* singleMaterialPatch, IndexedSurfacePatch* multiMaterialPatch)
{
//First and last voxels in the region
const uint16_t firstX = regionX * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstY = regionY * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t firstZ = regionZ * POLYVOX_REGION_SIDE_LENGTH;
const uint16_t lastX = (std::min)(firstX + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastY = (std::min)(firstY + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
const uint16_t lastZ = (std::min)(firstZ + POLYVOX_REGION_SIDE_LENGTH-1,volumeData->getSideLength()-2);
//Offset from lower block corner
const Vector3DFloat offset(firstX,firstY,firstZ);
Vector3DFloat vertlist[12];
uint8_t vertMaterials[12];
VolumeIterator<boost::uint8_t> volIter(*volumeData);
volIter.setValidRegion(firstX,firstY,firstZ,lastX,lastY,lastZ);
const float threshold = 0.5f;
//////////////////////////////////////////////////////////////////////////
//Get mesh data
//////////////////////////////////////////////////////////////////////////
//Iterate over each cell in the region
for(volIter.setPosition(firstX,firstY,firstZ);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
VolumeIterator<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.x();
const float posY = position.y();
const float posZ = position.z();
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;
VolumeIterator<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) * -1.0);
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) * -1.0);
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;
}
}