assimp/code/JoinVerticesProcess.cpp

316 lines
12 KiB
C++

/*
---------------------------------------------------------------------------
Open Asset Import Library (ASSIMP)
---------------------------------------------------------------------------
Copyright (c) 2006-2008, ASSIMP Development Team
All rights reserved.
Redistribution and use of this software in source and binary forms,
with or without modification, are permitted provided that the following
conditions are met:
* Redistributions of source code must retain the above
copyright notice, this list of conditions and the
following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the
following disclaimer in the documentation and/or other
materials provided with the distribution.
* Neither the name of the ASSIMP team, nor the names of its
contributors may be used to endorse or promote products
derived from this software without specific prior
written permission of the ASSIMP Development Team.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
---------------------------------------------------------------------------
*/
/** @file Implementation of the post processing step to join identical vertices
* for all imported meshes
*/
#include <vector>
#include <assert.h>
#include "JoinVerticesProcess.h"
#include "SpatialSort.h"
#include "../include/DefaultLogger.h"
#include "../include/aiPostProcess.h"
#include "../include/aiMesh.h"
#include "../include/aiScene.h"
using namespace Assimp;
// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
JoinVerticesProcess::JoinVerticesProcess()
{
// nothing to do here
}
// ------------------------------------------------------------------------------------------------
// Destructor, private as well
JoinVerticesProcess::~JoinVerticesProcess()
{
// nothing to do here
}
// ------------------------------------------------------------------------------------------------
// Returns whether the processing step is present in the given flag field.
bool JoinVerticesProcess::IsActive( unsigned int pFlags) const
{
return (pFlags & aiProcess_JoinIdenticalVertices) != 0;
}
// ------------------------------------------------------------------------------------------------
// Executes the post processing step on the given imported data.
void JoinVerticesProcess::Execute( aiScene* pScene)
{
DefaultLogger::get()->debug("JoinVerticesProcess begin");
bool bHas = false;
for( unsigned int a = 0; a < pScene->mNumMeshes; a++)
{
if( this->ProcessMesh( pScene->mMeshes[a]))
bHas = true;
}
if (bHas)DefaultLogger::get()->info("JoinVerticesProcess finished. Found vertices to join");
else DefaultLogger::get()->debug("JoinVerticesProcess finished. There was nothing to do.");
}
// ------------------------------------------------------------------------------------------------
// Unites identical vertices in the given mesh
bool JoinVerticesProcess::ProcessMesh( aiMesh* pMesh)
{
// helper structure to hold all the data a single vertex can possibly have
typedef struct Vertex vertex;
struct Vertex
{
aiVector3D mPosition;
aiVector3D mNormal;
aiVector3D mTangent, mBitangent;
aiColor4D mColors[AI_MAX_NUMBER_OF_COLOR_SETS];
aiVector3D mTexCoords[AI_MAX_NUMBER_OF_TEXTURECOORDS];
};
std::vector<Vertex> uniqueVertices;
uniqueVertices.reserve( pMesh->mNumVertices);
unsigned int iOldVerts = pMesh->mNumVertices;
// For each vertex the index of the vertex it was replaced by.
std::vector<unsigned int> replaceIndex( pMesh->mNumVertices, 0xffffffff);
// for each vertex whether it was replaced by an existing unique vertex (true) or a new vertex was created for it (false)
std::vector<bool> isVertexUnique( pMesh->mNumVertices, false);
// calculate the position bounds so we have a reliable epsilon to check position differences against
aiVector3D minVec( 1e10f, 1e10f, 1e10f), maxVec( -1e10f, -1e10f, -1e10f);
for( unsigned int a = 0; a < pMesh->mNumVertices; a++)
{
minVec.x = std::min( minVec.x, pMesh->mVertices[a].x);
minVec.y = std::min( minVec.y, pMesh->mVertices[a].y);
minVec.z = std::min( minVec.z, pMesh->mVertices[a].z);
maxVec.x = std::max( maxVec.x, pMesh->mVertices[a].x);
maxVec.y = std::max( maxVec.y, pMesh->mVertices[a].y);
maxVec.z = std::max( maxVec.z, pMesh->mVertices[a].z);
}
// squared because we check against squared length of the vector difference
const float epsilon = 1e-5f;
const float posEpsilon = (maxVec - minVec).Length() * epsilon;
const float squareEpsilon = epsilon * epsilon;
// a little helper to find locally close vertices faster
SpatialSort vertexFinder( pMesh->mVertices, pMesh->mNumVertices, sizeof( aiVector3D));
std::vector<unsigned int> verticesFound;
// now check each vertex if it brings something new to the table
for( unsigned int a = 0; a < pMesh->mNumVertices; a++)
{
// collect the vertex data
Vertex v;
v.mPosition = pMesh->mVertices[a];
v.mNormal = (pMesh->mNormals != NULL) ? pMesh->mNormals[a] : aiVector3D( 0, 0, 0);
v.mTangent = (pMesh->mTangents != NULL) ? pMesh->mTangents[a] : aiVector3D( 0, 0, 0);
v.mBitangent = (pMesh->mBitangents != NULL) ? pMesh->mBitangents[a] : aiVector3D( 0, 0, 0);
for( unsigned int b = 0; b < AI_MAX_NUMBER_OF_COLOR_SETS; b++)
v.mColors[b] = (pMesh->mColors[b] != NULL) ? pMesh->mColors[b][a] : aiColor4D( 0, 0, 0, 0);
for( unsigned int b = 0; b < AI_MAX_NUMBER_OF_TEXTURECOORDS; b++)
v.mTexCoords[b] = (pMesh->mTextureCoords[b] != NULL) ? pMesh->mTextureCoords[b][a] : aiVector3D( 0, 0, 0);
// collect all vertices that are close enough to the given position
vertexFinder.FindPositions( v.mPosition, posEpsilon, verticesFound);
unsigned int matchIndex = 0xffffffff;
// check all unique vertices close to the position if this vertex is already present among them
for( unsigned int b = 0; b < verticesFound.size(); b++)
{
unsigned int vidx = verticesFound[b];
unsigned int uidx = replaceIndex[ vidx];
if( uidx == 0xffffffff || !isVertexUnique[ vidx])
continue;
const Vertex& uv = uniqueVertices[ uidx];
// Position mismatch is impossible - the vertex finder already discarded all non-matching positions
// We just test the other attributes even if they're not present in the mesh.
// In this case they're initialized to 0 so the comparision succeeds.
// By this method the non-present attributes are effectively ignored in the comparision.
if( (uv.mNormal - v.mNormal).SquareLength() > squareEpsilon)
continue;
if( (uv.mTangent - v.mTangent).SquareLength() > squareEpsilon)
continue;
if( (uv.mBitangent - v.mBitangent).SquareLength() > squareEpsilon)
continue;
// manually unrolled because continue wouldn't work as desired in an inner loop
assert( AI_MAX_NUMBER_OF_COLOR_SETS == 4);
if( GetColorDifference( uv.mColors[0], v.mColors[0]) > squareEpsilon)
continue;
if( GetColorDifference( uv.mColors[1], v.mColors[1]) > squareEpsilon)
continue;
if( GetColorDifference( uv.mColors[2], v.mColors[2]) > squareEpsilon)
continue;
if( GetColorDifference( uv.mColors[3], v.mColors[3]) > squareEpsilon)
continue;
// texture coord matching manually unrolled as well
assert( AI_MAX_NUMBER_OF_TEXTURECOORDS == 4);
if( (uv.mTexCoords[0] - v.mTexCoords[0]).SquareLength() > squareEpsilon)
continue;
if( (uv.mTexCoords[1] - v.mTexCoords[1]).SquareLength() > squareEpsilon)
continue;
if( (uv.mTexCoords[2] - v.mTexCoords[2]).SquareLength() > squareEpsilon)
continue;
if( (uv.mTexCoords[3] - v.mTexCoords[3]).SquareLength() > squareEpsilon)
continue;
// we're still here -> this vertex perfectly matches our given vertex
matchIndex = uidx;
break;
}
// found a replacement vertex among the uniques?
if( matchIndex != 0xffffffff)
{
// store where to found the matching unique vertex
replaceIndex[a] = matchIndex;
isVertexUnique[a] = false;
} else
{
// no unique vertex matches it upto now -> so add it
replaceIndex[a] = (unsigned int)uniqueVertices.size();
uniqueVertices.push_back( v);
isVertexUnique[a] = true;
}
}
// replace vertex data with the unique data sets
pMesh->mNumVertices = (unsigned int)uniqueVertices.size();
// Position
delete [] pMesh->mVertices;
pMesh->mVertices = new aiVector3D[pMesh->mNumVertices];
for( unsigned int a = 0; a < pMesh->mNumVertices; a++)
pMesh->mVertices[a] = uniqueVertices[a].mPosition;
// Normals, if present
if( pMesh->mNormals)
{
delete [] pMesh->mNormals;
pMesh->mNormals = new aiVector3D[pMesh->mNumVertices];
for( unsigned int a = 0; a < pMesh->mNumVertices; a++)
pMesh->mNormals[a] = uniqueVertices[a].mNormal;
}
// Tangents, if present
if( pMesh->mTangents)
{
delete [] pMesh->mTangents;
pMesh->mTangents = new aiVector3D[pMesh->mNumVertices];
for( unsigned int a = 0; a < pMesh->mNumVertices; a++)
pMesh->mTangents[a] = uniqueVertices[a].mTangent;
}
// Bitangents as well
if( pMesh->mBitangents)
{
delete [] pMesh->mBitangents;
pMesh->mBitangents = new aiVector3D[pMesh->mNumVertices];
for( unsigned int a = 0; a < pMesh->mNumVertices; a++)
pMesh->mBitangents[a] = uniqueVertices[a].mBitangent;
}
// Vertex colors
for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_COLOR_SETS; a++)
{
if( !pMesh->mColors[a])
continue;
delete [] pMesh->mColors[a];
pMesh->mColors[a] = new aiColor4D[pMesh->mNumVertices];
for( unsigned int b = 0; b < pMesh->mNumVertices; b++)
pMesh->mColors[a][b] = uniqueVertices[b].mColors[a];
}
// Texture coords
for( unsigned int a = 0; a < AI_MAX_NUMBER_OF_TEXTURECOORDS; a++)
{
if( !pMesh->mTextureCoords[a])
continue;
delete [] pMesh->mTextureCoords[a];
pMesh->mTextureCoords[a] = new aiVector3D[pMesh->mNumVertices];
for( unsigned int b = 0; b < pMesh->mNumVertices; b++)
pMesh->mTextureCoords[a][b] = uniqueVertices[b].mTexCoords[a];
}
// adjust the indices in all faces
for( unsigned int a = 0; a < pMesh->mNumFaces; a++)
{
aiFace& face = pMesh->mFaces[a];
for( unsigned int b = 0; b < face.mNumIndices; b++)
{
const size_t index = face.mIndices[b];
face.mIndices[b] = replaceIndex[face.mIndices[b]];
}
}
// adjust bone vertex weights.
for( unsigned int a = 0; a < pMesh->mNumBones; a++)
{
aiBone* bone = pMesh->mBones[a];
std::vector<aiVertexWeight> newWeights;
newWeights.reserve( bone->mNumWeights);
for( unsigned int b = 0; b < bone->mNumWeights; b++)
{
const aiVertexWeight& ow = bone->mWeights[b];
// if the vertex is a unique one, translate it
if( isVertexUnique[ow.mVertexId])
{
aiVertexWeight nw;
nw.mVertexId = replaceIndex[ow.mVertexId];
nw.mWeight = ow.mWeight;
newWeights.push_back( nw);
}
}
// there should be some. At least I think there should be some
assert( newWeights.size() > 0);
// kill the old and replace them with the translated weights
delete [] bone->mWeights;
bone->mNumWeights = (unsigned int)newWeights.size();
bone->mWeights = new aiVertexWeight[bone->mNumWeights];
memcpy( bone->mWeights, &newWeights[0], bone->mNumWeights * sizeof( aiVertexWeight));
}
return (iOldVerts != pMesh->mNumVertices);
}