void TriMesh::computeFaceGrad(const VectorXd& vertForm, std::vector<Vec3>& faceVector) const
{
faceVector.resize(numFaces());
for (unsigned face = 0; face < numFaces(); ++face)
{
std::vector<unsigned> fVert;
getFaceVerts(face, fVert);
assert(fVert.size() == 3);
Vec3 pos[3];
double val[3];
for (unsigned i = 0; i < 3; ++i)
{
val[i] = vertForm(fVert[i]);
pos[i] = getVertPos(fVert[i]);
}
Vec3 X = Vec3::Zero();
for (unsigned i = 0; i < 3; ++i)
{
unsigned j = (i + 1) % 3;
unsigned k = (i + 2) % 3;
X += val[i] * (pos[k] - pos[j]);
}
Vec3 n = (pos[1]-pos[0]).cross(pos[2]-pos[1]);
double twice_area = n.norm();
n /= twice_area;
faceVector[face] = n.cross(X) / twice_area;
}
}
void extractInternalFaces(const Dune::CpGrid& grid,
Eigen::Array<int, Eigen::Dynamic, 1>& internal_faces,
Eigen::Array<int, Eigen::Dynamic, 2, Eigen::RowMajor>& nbi)
{
// Extracts the internal faces of the grid.
// These are stored in internal_faces.
int nf=numFaces(grid);
int num_internal=0;
for(int f=0; f<nf; ++f)
{
if(grid.faceCell(f, 0)<0 || grid.faceCell(f, 1)<0)
continue;
++num_internal;
}
// std::cout << num_internal << " internal faces." << std::endl;
nbi.resize(num_internal, 2);
internal_faces.resize(num_internal);
int fi = 0;
for (int f = 0; f < nf; ++f) {
if(grid.faceCell(f, 0)>=0 && grid.faceCell(f, 1)>=0) {
internal_faces[fi] = f;
nbi(fi,0) = grid.faceCell(f, 0);
nbi(fi,1) = grid.faceCell(f, 1);
++fi;
}
}
}
void extractInternalFaces(const UnstructuredGrid& grid,
Eigen::Array<int, Eigen::Dynamic, 1>& internal_faces,
Eigen::Array<int, Eigen::Dynamic, 2, Eigen::RowMajor>& nbi)
{
typedef Eigen::Array<bool, Eigen::Dynamic, 1> OneColBool;
typedef Eigen::Array<int, Eigen::Dynamic, 2, Eigen::RowMajor> TwoColInt;
typedef Eigen::Array<bool, Eigen::Dynamic, 2, Eigen::RowMajor> TwoColBool;
TwoColInt nb = faceCells(grid);
// std::cout << "nb = \n" << nb << std::endl;
// Extracts the internal faces of the grid.
// These are stored in internal_faces.
TwoColBool nbib = nb >= 0;
OneColBool ifaces = nbib.rowwise().all();
const int num_internal = ifaces.cast<int>().sum();
// std::cout << num_internal << " internal faces." << std::endl;
nbi.resize(num_internal, 2);
internal_faces.resize(num_internal);
int fi = 0;
int nf = numFaces(grid);
for (int f = 0; f < nf; ++f) {
if (ifaces[f]) {
internal_faces[fi] = f;
nbi.row(fi) = nb.row(f);
++fi;
}
}
}
double TriMesh::computeTotalArea() const
{
double sum = 0.0;
for (unsigned face = 0; face < numFaces(); ++face)
sum += computeFaceArea(face);
return sum;
}
void OBJGroup::addFace( const OBJFace& face )
{
m_faces.push_back( face );
const std::string& lastMaterial = m_materialNames.back();
m_facesByMaterial[ lastMaterial ].push_back( numFaces() - 1 );
}
// for each face according to its vertices orientation
void Mesh::compute_normals_per_facet()
{
for(int i = 0; i < numFaces(); ++i)
{
Face &face = m_face[i];
face.computeNormal();
}
}
void Mesh::Vertex::computeNormal()
{
for(int i = 0; i < numFaces(); ++i)
{
Face_handle v = face(i);
m_normal += v->normal();
}
m_normal.unitize();
}
bool BspSceneFile::loadFaces(std::istream& bspStream, const Q3Bsp::DirEntry& facesEntry) {
if (!bspStream.seekg(facesEntry.offset, std::ios::beg)) {
return false;
}
std::size_t numFaces(facesEntry.length / sizeof(Q3Bsp::Face));
m_faces.reserve(numFaces);
if (!bspStream.read(reinterpret_cast<char*>(&m_faces[0]), facesEntry.length)) {
return false;
}
return true;
}
void Mesh::buildEdges()
{
TSmallLargeEdgeI edgeMap;
edgeMap.clear();
// map small index to map large index to the edge in the m_edge list
for(int fi = 0; fi < numFaces(); ++fi)
{
//printf("%d- ", fi);
Face &face = m_face[fi];
int v0i = face.vertexIndex(0);
int v1i = face.vertexIndex(1);
int v2i = face.vertexIndex(2);
int e0i = addEdgeOnceUsing(v0i, v1i, edgeMap, &Mesh::addEdge);
int e1i = addEdgeOnceUsing(v1i, v2i, edgeMap, &Mesh::addEdge);
int e2i = addEdgeOnceUsing(v2i, v0i, edgeMap, &Mesh::addEdge);
face.m_edges[0] = e0i;
face.m_edges[1] = e1i;
face.m_edges[2] = e2i;
/* Vertex_handle v0 = find_vertex(v0i);
v0->m_edges.append(e0i);
v0->m_edges.append(e2i);
Vertex_handle v1 = find_vertex(v1i);
v1->m_edges.append(e0i);
v1->m_edges.append(e1i);
Vertex_handle v2 = find_vertex(v2i);
v2->m_edges.append(e1i);
v2->m_edges.append(e2i);*/
///printf("%d %d %d\n", e0i, e1i, e2i);
find_edge(e0i)->m_faces.append(fi);
find_edge(e1i)->m_faces.append(fi);;
find_edge(e2i)->m_faces.append(fi);
// don't keep pointers since the vector might be reallocated
// make sure the shortest one is in edges[0]
/*if (e2->length() < e1->length())
qSwap(e2, e1);
if (e1->length() < e0)->length())
qSwap(e1, e0);
if (find_edge(e2)->length() < find_edge(e1)->length())
qSwap(e2, e1); don't need that */
}
}
void TriMesh::computeVertArea(VectorXd& vertArea) const
{
vertArea = VectorXd::Zero(numVerts());
for (unsigned face = 0; face < numFaces(); ++face)
{
std::vector<unsigned> fVert;
getFaceVerts(face, fVert);
assert(fVert.size() == 3);
double faceArea = computeFaceArea(face);
for (unsigned i = 0; i < 3; ++i) vertArea(fVert[i]) += faceArea;
}
vertArea /= 3.0;
}
//reads in an object from a .obj file
BasicObject::BasicObject(const std::string &filename, const float _shininess){
shininess = _shininess;
_numVerticies = numVertices(filename.c_str());
_numFaces = numFaces(filename.c_str());
_indexCount = _numFaces * 3;
verticies = getVertices(filename.c_str(), _numVerticies);
normals = getNormals(filename.c_str(), _numVerticies);
faces = getFaces(filename.c_str(), _numFaces);
texCoords = getTextureCoords(filename.c_str(), _numVerticies);
}
void Mesh::commitRemove()
{
// first go over all the points and tell them where they go
int count = 0;
for(int i = 0; i < numVtx(); ++i)
{
Vertex_handle v = find_vertex(i);
if (v->m_tran == -1)
v->m_index = count++;
else
v->m_index = -1; // to be removed
v->m_tran = -1;
}
// no go over the faces and transfer their point references
count = 0;
for(int i = 0; i < numFaces(); ++i)
{
Face_handle f = find_facet(i);
bool remove = false;
for(int ii = 0; ii < f->size(); ++ii)
{
int newvi = find_vertex(f->m_pi[ii])->m_index;
f->m_pi[ii] = newvi;
remove |= (newvi == -1);
}
if (!remove)
f->m_index = count++;
else
f->m_index = -1;
}
// actually remove the vertices
Vertex_iterator vit = vertices_begin();
while(vit != vertices_end())
{
if (vit->m_index == -1)
vit = m_vtx.erase(vit);
else
++vit;
}
// remove faces
Face_iterator fit = faces_begin();
while(fit != faces_end())
{
if (fit->m_index == -1)
fit = m_face.erase(fit);
else
++fit;
}
}
void Mesh::buildVerticesInFaces()
{
for(int i = 0; i < numVtx(); ++i)
{
Vertex &v = m_vtx[i];
v.faceIndexs().clear();
}
for(int fi = 0; fi < numFaces(); ++fi)
{
Face &face = m_face[fi];
for(int i = 0; i < face.size(); ++i)
{
m_vtx[face.vertexIndex(i)].faceIndexs().push_back(fi);
}
}
}
float Mesh::compute_triangle_surfaces()
{
m_totalSurface = 0.0;
for(int i = 0; i < numFaces(); ++i)
{
Face &face = m_face[i];
Vec3 v1(face.vertex(1)->point(), face.vertex(0)->point());
Vec3 v2(face.vertex(2)->point(), face.vertex(0)->point());
Vec3 cross = Vec3::crossProd(v1, v2);
face.surface() = cross.length() / 2.0f;
m_totalSurface += face.surface();
}
return m_totalSurface;
}
// only triangles
Mesh::TIndexList Mesh::Vertex::neiVertices() const
{
TIndexList ret;
for(int i = 0; i < numFaces(); ++i)
{
Face_const_handle f = face(i);
for(int vi = 0; vi < f->size(); ++vi)
{
int cv = f->vertexIndex(vi);
if (cv != index() && !ret.contains(cv))
ret.append(cv);
}
}
return ret;
}
void TriMesh::computeDivergence(const std::vector<Vec3>& faceVector, VectorXd& vertForm) const
{
vertForm = VectorXd::Zero(numVerts());
for (unsigned face = 0; face < numFaces(); ++face)
{
std::vector<unsigned> fVert;
getFaceVerts(face, fVert);
assert(fVert.size() == 3);
Vec3 n = computeFaceNormal(face);
for (unsigned i = 0; i < 3; ++i)
{
Vec3 p1 = getVertPos(fVert[(i+1)%3]);
Vec3 p2 = getVertPos(fVert[(i+2)%3]);
vertForm[fVert[i]] += 0.5*faceVector[face].dot(n.cross(p2-p1));
}
}
}
double TriMesh::computeMaxEdgeLength() const
{
double maxLen = 0.0;
for (unsigned face = 0; face < numFaces(); ++face)
{
std::vector<unsigned> fVerts;
getFaceVerts(face, fVerts);
assert(fVerts.size() == 3);
for (unsigned i = 0; i < 3; ++i)
{
unsigned vert0 = fVerts[(i+1)%3];
unsigned vert1 = fVerts[(i+2)%3];
double len = computeEdgeLength(vert0, vert1);
maxLen = std::max(maxLen, len);
}
}
return maxLen;
}
void TriMesh::buildHeatKernel(SparseMatrix& A, double timestep) const
{
VectorXd diag;
computeVertArea(diag);
std::map< std::pair<unsigned,unsigned>, double > offdiag;
for (unsigned face = 0; face < numFaces(); ++face)
{
std::vector<unsigned> fVert;
getFaceVerts(face, fVert);
assert(fVert.size() == 3);
for (unsigned i = 0; i < 3; ++i)
{
unsigned vert0 = fVert[(i+1)%3];
unsigned vert1 = fVert[(i+2)%3];
if (vert0 > vert1) std::swap(vert0, vert1);
std::pair<unsigned,unsigned> edge(vert0,vert1);
double value = timestep * 0.5 * computeFaceCotan(face, i);
diag(vert0) += value;
diag(vert1) += value;
if (offdiag.find(edge) == offdiag.end())
offdiag[edge] = -value;
else
offdiag[edge] -= value;
}
}
std::vector<Triplet> triplet;
for(unsigned i = 0; i < diag.size(); ++i)
{
triplet.push_back(Triplet(i,i,diag(i)));
}
for(std::map< std::pair<unsigned,unsigned>, double >::const_iterator
it = offdiag.begin(); it != offdiag.end(); ++it)
{
triplet.push_back(Triplet(it->first.first,it->first.second,it->second));
triplet.push_back(Triplet(it->first.second,it->first.first,it->second));
}
A.resize(numVerts(), numVerts());
A.setFromTriplets(triplet.begin(),triplet.end());
}
void Mesh::makeClosenessEdges()
{
int hasCount = 0;
TSmallLargeEdgeI makec;
for(int fi = 0; fi < numFaces(); ++fi)
{
Face_const_handle f = find_facet(fi);
const TIndexList& clsf = f->closeFaces();
if (clsf.size() == 0)
continue;
++hasCount;
for(int cfi = 0; cfi < clsf.size(); ++cfi)
{
addEdgeOnceUsing(fi, clsf[cfi], makec, &Mesh::addCloseEdge);
}
}
printf("Faces with close edges=%d\n", hasCount);
}
void TriMesh::computeVertNormals(std::vector<Vec3>& vertNormal) const
{
vertNormal = std::vector<Vec3>(numVerts(), Vec3::Zero());
for (unsigned face = 0; face < numFaces(); ++face)
{
std::vector<unsigned> fVert;
getFaceVerts(face, fVert);
assert(fVert.size() == 3);
double faceArea = computeFaceArea(face);
Vec3 faceNormal = computeFaceNormal(face);
for (unsigned i = 0; i < 3; ++i)
vertNormal[fVert[i]] += faceArea * faceNormal;
}
for (unsigned vert = 0; vert < numVerts(); ++vert)
{
vertNormal[vert].normalize();
}
}
Vec3 Mesh::centerOfMass()
{
// compute for every face
for(int i = 0; i < numFaces(); ++i)
{
Face &f = m_face[i];
f.m_center.clear();
for(int i = 0; i < f.size(); ++i)
f.m_center += f.vertex(i)->point();
f.m_center /= f.size();
}
// now for all of the mess seperatly.
Vec3 centerOfMass(0,0,0);
for (Mesh::Vertex_iterator v = this->vertices_begin(); v != this->vertices_end(); v++)
{
centerOfMass = centerOfMass + (v->point()); // - CGAL::ORIGIN);
}
unsigned int size = this->size_of_vertices();
m_computedCenterOfMass = Vec3(centerOfMass.x/size, centerOfMass.y/size, centerOfMass.z/size);
return m_computedCenterOfMass;
}
void Mesh::saveSubMesh(const QString& filename, const TIndexList& facesList) const
{
QFile file(filename);
file.open(QFile::WriteOnly | QFile::Truncate);
file.setTextModeEnabled(true);
QTextStream out(&file);
out << "OFF\n";
int nVtx = numVtx();
int newIndexCounter = 0;
// do we need only a subset of the vertices?
QVector<int> newToOld;
QHash<int, int> oldToNew; // old index -> new index.
if (facesList.size() != numFaces())
{
for(TIndexList::const_iterator pfi = facesList.constBegin(); pfi != facesList.constEnd(); ++pfi)
{
Face_const_handle f = find_facet(*pfi);
for(int vfi = 0; vfi < f->size(); ++vfi)
{
int vi = f->vertexIndex(vfi);
if (!oldToNew.contains(vi))
oldToNew.insert(vi, newIndexCounter++);
}
}
newToOld.resize(newIndexCounter);
// invert the map because we want a map from new to old
for(QHash<int, int>::iterator hit = oldToNew.begin(); hit != oldToNew.end(); ++hit)
{
newToOld[hit.value()] = hit.key();
}
nVtx = newIndexCounter;
}
// number of vertices, faces, 0
out << nVtx << " " << facesList.size() << " 0\n";
for(int i = 0; i < nVtx; ++i)
{
Vertex_const_handle v;
if (newIndexCounter > 0)
v = find_vertex(newToOld[i]);
else
v = find_vertex(i);
const Vec3 &p = v->point();
out << p.x << " " << p.y << " " << p.z << "\n";
}
for(TIndexList::const_iterator pfi = facesList.constBegin(); pfi != facesList.constEnd(); ++pfi)
{
Face_const_handle f = find_facet(*pfi);
out << f->size();
for(int vfi = 0; vfi < f->size(); ++vfi)
{
int fii = f->vertexIndex(vfi);
if (newIndexCounter > 0)
fii = oldToNew[fii];
out << " " << fii;
}
out << "\n";
}
}
SparseTableView face2Vertices(const UnstructuredGrid& grid)
{
return SparseTableView(grid.face_nodes, grid.face_nodepos, numFaces(grid));
}
