static void mergeBones( BoneList &a, BoneList& b ) {
for (size_t i=0; i<b.size(); ++i) {
int c = b[i];
BoneList::iterator it = find(a.begin(), a.end(), c);
if ( a.end() == it ) {
a.push_back( c );
}
}
}
static bool containsBones( BoneList& a, BoneList& b ) {
for (size_t i=0; i<b.size(); ++i) {
int c = b[i];
BoneList::iterator it = find(a.begin(), a.end(), c);
if ( a.end() == it ) {
return false;
}
}
return true;
}
NiSkinPartition::NiSkinPartition(Ref<NiTriBasedGeom> shape, int maxBonesPerPartition, int maxBonesPerVertex ) {
NiSkinInstanceRef skinInst = shape->GetSkinInstance();
if ( skinInst == NULL ) {
throw runtime_error( "You must bind a skin before setting generating skin partitions. No NiSkinInstance found." );
}
NiSkinDataRef skinData = skinInst->GetSkinData();
if ( skinData == NULL ) {
throw runtime_error( "You must bind a skin before setting generating skin partitions. No NiSkinData found." );
}
NiTriBasedGeomDataRef geomData = DynamicCast<NiTriBasedGeomData>(shape->GetData() );
if ( geomData == NULL ) {
throw runtime_error( "Attempted to generate a skin partition on a mesh with no geometry data." );
}
// read in the weights from NiSkinData
vector<Vector3> verts = geomData->GetVertices();
vector< BoneWeightList > weights;
if (verts.empty()){
throw runtime_error( "Attempted to generate a skin partition on a mesh with no vertices." );
}
Triangles triangles = geomData->GetTriangles();
if (triangles.empty()) {
throw runtime_error( "Attempted to generate a skin partition on a mesh with no triangles." );
}
weights.resize( verts.size() );
int numBones = skinData->GetBoneCount();
for ( int bone = 0; bone < numBones; bone++ )
{
vector<SkinWeight> vertexWeights = skinData->GetBoneWeights(bone);
for (int r = 0; r < int(vertexWeights.size()); ++r ){
int vertex = vertexWeights[r].index;
float weight = vertexWeights[r].weight;
if ( vertex >= int(weights.size()) )
throw runtime_error( "bad NiSkinData - vertex count does not match" );
weights[vertex].insert( weights[vertex].end(), BoneWeight(bone, weight) );
}
}
// count min and max bones per vertex
int minBones, maxBones;
minBones = maxBones = weights[0].size();
for(vector< BoneWeightList >::iterator itr = weights.begin(); itr != weights.end(); ++itr ){
int n = (*itr).size();
minBones = min(n, minBones);
maxBones = max(n, maxBones);
}
if ( minBones <= 0 )
throw runtime_error( "bad NiSkinData - some vertices have no weights at all" );
// reduce vertex influences if necessary
if ( maxBones > maxBonesPerVertex )
{
int c = 0;
for ( vector< BoneWeightList >::iterator it = weights.begin(); it != weights.end(); ++it )
{
BoneWeightList & lst = *it;
if ( int(lst.size()) > maxBonesPerVertex )
c++;
while ( int(lst.size()) > maxBonesPerVertex ) {
int j = 0;
float weight = lst.front().second;
for ( int i = 0; i < int(lst.size()); i++ )
{
if ( lst[i].second < weight )
j = i;
}
BoneWeightList::iterator jit = lst.begin() + j;
lst.erase( jit );
}
float totalWeight = 0;
for (BoneWeightList::iterator bw = lst.begin(); bw != lst.end(); ++bw) {
totalWeight += (*bw).second;
}
for (BoneWeightList::iterator bw = lst.begin(); bw != lst.end(); ++bw) {
(*bw).second /= totalWeight;
}
}
//qWarning() << "reduced" << c << "vertices to" << maxBonesPerVertex << "bone influences (maximum number of bones per vertex was" << maxBones << ")";
}
maxBones = maxBonesPerVertex;
// reduces bone weights so that the triangles fit into the partitions
typedef multimap<int,int> matchmap;
typedef pair<matchmap::iterator, matchmap::iterator> matchrange;
matchmap match;
bool doMatch = true;
BoneList tribones;
int cnt = 0;
for (Triangles::iterator itr = triangles.begin(); itr != triangles.end(); ++itr) {
Triangle& tri = (*itr);
do
{
tribones.clear();
for ( int c = 0; c < 3; c++ ) {
BoneWeightList& bwl = weights[tri[c]];
for (BoneWeightList::iterator bw = bwl.begin(); bw != bwl.end(); ++bw) {
if ( tribones.end() == find(tribones.begin(), tribones.end(), (*bw).first ) )
tribones.insert(tribones.end(), (*bw).first );
}
}
if ( int(tribones.size()) > maxBonesPerPartition )
{
// sum up the weights for each bone
// bones with weight == 1 can't be removed
map<int, float> sum;
vector<int> nono;
for ( int t = 0; t < 3; t++ ) {
BoneWeightList& bwl = weights[tri[t]];
if ( bwl.size() == 1 )
nono.insert(nono.end(), bwl.front().first );
for (BoneWeightList::iterator bw = bwl.begin(); bw != bwl.end(); ++bw) {
sum[ (*bw).first ] += (*bw).second;
}
}
// select the bone to remove
float minWeight = 5.0;
int minBone = -1;
for (map<int, float>::iterator sitr = sum.begin(); sitr != sum.end(); ++sitr) {
int b = (*sitr).first;
if ( (find(nono.begin(), nono.end(), b) == nono.end()) && sum[b] < minWeight) {
minWeight = sum[b];
minBone = b;
}
}
if ( minBone < 0 ) // this shouldn't never happen
throw runtime_error( "internal error 0x01" );
// do a vertex match detect
if ( doMatch ) {
for ( size_t a = 0; a < verts.size(); a++ ) {
match.insert(matchmap::value_type(a, a));
for ( size_t b = a + 1; b < verts.size(); b++ ) {
if ( verts[a] == verts[b] && weights[a] == weights[b] ) {
match.insert(matchmap::value_type(a, b));
match.insert(matchmap::value_type(b, a));
}
}
}
}
// now remove that bone from all vertices of this triangle and from all matching vertices too
for ( int t = 0; t < 3; t++ ) {
bool rem = false;
matchrange range = match.equal_range(tri[t]);
for (matchmap::iterator itr = range.first; itr != range.second; ++itr) {
int v = (*itr).second;
BoneWeightList & bws = weights[ v ];
BoneWeightList::iterator it = bws.begin();
while ( it != bws.end() ) {
BoneWeight & bw = *it;
if ( bw.first == minBone ) {
it = bws.erase(it);
rem = true;
} else {
++it;
}
}
float totalWeight = 0;
for (BoneWeightList::iterator bw = bws.begin(); bw != bws.end(); ++bw) {
totalWeight += (*bw).second;
}
if ( totalWeight == 0 )
throw runtime_error( "internal error 0x02" );
// normalize
for (BoneWeightList::iterator bw = bws.begin(); bw != bws.end(); ++bw) {
(*bw).second /= totalWeight;
}
}
if ( rem )
cnt++;
}
}
} while ( int(tribones.size()) > maxBonesPerPartition );
}
//if ( cnt > 0 )
// qWarning() << "removed" << cnt << "bone influences";
PartitionList& parts = skinPartitionBlocks;
// split the triangles into partitions
while ( ! triangles.empty() ) {
SkinPartition part;
Triangles::iterator it = triangles.begin();
while ( it != triangles.end() ) {
Triangle & tri = *it;
BoneList tribones;
for ( int c = 0; c < 3; c++ ) {
BoneWeightList& bws = weights[tri[c]];
for (BoneWeightList::iterator bw = bws.begin(); bw != bws.end(); ++bw) {
if ( tribones.end() == find(tribones.begin(), tribones.end(), (*bw).first ) )
tribones.push_back( (*bw).first );
}
}
if ( part.bones.empty() || containsBones( part.bones, tribones ) ) {
mergeBones( part.bones, tribones );
part.triangles.push_back( tri );
it = triangles.erase(it);
} else {
++it;
}
}
parts.push_back( part );
}
//qWarning() << parts.size() << "small partitions";
// merge partitions
bool merged;
do
{
merged = false;
// Working backwards through this list minimizes numbers of swaps
//for ( int p2 = int(parts.size()-1); p2 >= 0 && ! merged; --p2 )
//{
// Partition& part2 = parts[p2];
// for ( int p1 = int(p2-1); p1 >= 0 && ! merged; --p1 )
// {
// Partition& part1 = parts[p1];
for ( int p1 = 0; p1 < int(parts.size()) && ! merged; p1++ )
{
Partition& part1 = parts[p1];
for ( int p2 = p1+1; p2 < int(parts.size()) && ! merged; p2++ )
{
Partition& part2 = parts[p2];
BoneList mergedBones = part1.bones;
mergeBones( mergedBones, part2.bones );
if ( int(mergedBones.size()) <= maxBonesPerPartition )
{
PartitionList::iterator p2i = parts.begin() + p2;
part1.bones = mergedBones;
part1.triangles.insert(part1.triangles.end(), (*p2i).triangles.begin(), (*p2i).triangles.end());
parts.erase(p2i);
merged = true;
}
}
}
}
while ( merged );
//qWarning() << parts.size() << "partitions";
// start writing NiSkinPartition
for ( int p = 0; p < int(parts.size()); p++ )
{
Partition& part = parts[p];
BoneList& bones = part.bones;
sort( bones.begin(), bones.end() );
Triangles& triangles = part.triangles;
vector<unsigned short>& vertices = part.vertexMap;
for( Triangles::iterator tri = triangles.begin(); tri != triangles.end(); ++tri) {
for ( int t = 0; t < 3; t++ ) {
if ( vertices.end() == find(vertices.begin(), vertices.end(), (*tri)[t] ) )
vertices.push_back( (*tri)[t] );
}
}
sort( vertices.begin(), vertices.end() );
part.numVertices = vertices.size();
part.hasVertexMap = true;
// map the vertices
for ( int tri = 0; tri < int(triangles.size()); tri++ ) {
for ( int t = 0; t < 3; t++ ) {
triangles[tri][t] = indexOf(vertices.begin(), vertices.end(), triangles[tri][t]);
}
}
SetWeightsPerVertex(p, maxBones);
EnableVertexWeights(p, true);
EnableVertexBoneIndices(p, true);
// strippify the triangles
NiTriStripsDataRef data = new NiTriStripsData(triangles, true);
int nstrips = data->GetStripCount();
SetStripCount( p, nstrips );
for ( int i=0; i<nstrips; ++i ) {
SetStrip(p, i, data->GetStrip(i));
}
//// Special case for pre-stripped data
//unsigned short *data = new unsigned short[triangles.size() * 3 * 2];
//for (size_t i=0; i< triangles.size(); i++) {
// data[i * 3 + 0] = triangles[i][0];
// data[i * 3 + 1] = triangles[i][1];
// data[i * 3 + 2] = triangles[i][2];
//}
//PrimitiveGroup * groups = 0;
//unsigned short numGroups = 0;
//// GF 3+
//SetCacheSize(CACHESIZE_GEFORCE3);
//// don't generate hundreds of strips
//SetStitchStrips(true);
//GenerateStrips(data, triangles.size()*3, &groups, &numGroups);
//delete [] data;
//if (groups) {
// SetStripCount(p, numGroups);
// for (int g=0; g<numGroups; g++) {
// if (groups[g].type == PT_STRIP) {
// vector<Niflib::unsigned short> strip(groups[g].numIndices);
// for (size_t s=0; s<groups[g].numIndices; s++)
// strip[s] = groups[g].indices[s];
// SetStrip(p, g, strip);
// }
// }
// delete [] groups;
//}
// fill in vertex weights and bones
for (size_t v = 0; v < vertices.size(); ++v) {
BoneWeightList& bwl = weights[vertices[v]];
for ( int b = 0; b < maxBones; b++ ) {
part.boneIndices[v][b] = (int(bwl.size()) > b) ? indexOf(bones.begin(), bones.end(), bwl[b].first) : 0 ;
part.vertexWeights[v][b] = (int(bwl.size()) > b ? bwl[b].second : 0.0f);
}
}
}
}