float ConstantAlgorithmLSHTC::findConstant(InputData* pData,
vector<sRates>* pMu, vector<float>* pV)
{
const int numClasses = pData->getNumClasses();
vector<float> halfWeightsPerClass(numClasses);
vector<float> halfEdges(numClasses);
findConstantWeightsEdges(pData, halfWeightsPerClass, halfEdges);
float halfEdge = 0;
for (int l = 0; l < numClasses; ++l)
{
if (halfEdges[l] > 0)
(*pV)[l] = +1;
else
(*pV)[l] = -1;
halfEdge += (*pV)[l] * halfEdges[l];
(*pMu)[l].classIdx = l;
(*pMu)[l].rPls = halfWeightsPerClass[l] + (*pV)[l] * halfEdges[l];
(*pMu)[l].rMin = halfWeightsPerClass[l] - (*pV)[l] * halfEdges[l];
(*pMu)[l].rZero = (*pMu)[l].rPls + (*pMu)[l].rMin; // == weightsPerClass[l]
}
return 2 * halfEdge;
} // end of findConstant
void Graph::newEdgeAt(int a, int aPos, int b, int bPos, int abData, int baData)
{
if (!isEdge(a,b)) {
Node &na = node(a), &nb = node(b);
na.addNeighbor(b, abData, aPos);
if (!halfEdges())
nb.addNeighbor(a, baData, bPos);
else ASSERT(baData < 0);
}
}
void Graph::deleteEdge(int a, int pos) {
Node &na = node(a);
na.removeIndex(pos);
#if 0
{
int loc;
if (na.hasNeighbor(b, &loc)) {
na.removeIndex(loc);
if (!halfEdges()) {
Node &nb = node(b);
if (nb.hasNeighbor(a, &loc))
nb.removeIndex(loc);
}
}
}
#endif
}
void Graph::deleteNode(int id) {
#undef p2
#define p2(a) //pr(a)
p2(("Graph::deleteNode %d\n",id));
p2((" graph is \n%s",s() ));
Node &n = node(id);
p2((" node nTotal=%d\n",n.nTotal() ));
// don't remove edges if halfedges is active
if (!halfEdges()) {
for (int i = n.nTotal() - 1; i >= 0; i--) {
Node &m = node(n.edgeDest(i));
p2((" dest node is %s\n",m.s() ));
m.removeNeighbor(id);
}
}
nodesRC_.add(id);
p2((" after del, graph is \n%s",s() ));
}
bool MeshBuilder::buildMesh(const MeshData& data, Mesh& mesh)
{
std::map<std::pair<int, int>, int> edgeCount;
std::map<std::pair<int, int>, HalfEdgeIter> existingHalfEdges;
std::map<int, VertexIter> indexToVertex;
std::map<HalfEdgeIter, bool> hasFlipEdge;
preallocateMeshElements(data, mesh);
// insert vertices into mesh and map vertex indices to vertex pointers
for (unsigned int i = 0; i < data.positions.size(); i++) {
VertexIter vertex = mesh.vertices.insert(mesh.vertices.end(), Vertex());
vertex->position = data.positions[i];
vertex->he = isolated.begin();
indexToVertex[i] = vertex;
}
// insert uvs into mesh
for (unsigned int i = 0; i < data.uvs.size(); i++) {
VectorIter uv = mesh.uvs.insert(mesh.uvs.end(), Eigen::Vector3d());
*uv = data.uvs[i];
}
// insert normals into mesh
for (unsigned int i = 0; i < data.normals.size(); i++) {
VectorIter normal = mesh.normals.insert(mesh.normals.end(), Eigen::Vector3d());
*normal = data.normals[i];
}
// insert faces into mesh
int faceIndex = 0;
bool degenerateFaces = false;
for (std::vector<std::vector<Index>>::const_iterator f = data.indices.begin();
f != data.indices.end();
f ++) {
int n = (int)f->size();
// check if face is degenerate
if (n < 3) {
std::cerr << "Error: face " << faceIndex << " is degenerate" << std::endl;
degenerateFaces = true;
continue;
}
// create face
FaceIter newFace = mesh.faces.insert(mesh.faces.end(), Face());
// create a halfedge for each edge of the face
std::vector<HalfEdgeIter> halfEdges(n);
for (int i = 0; i < n; i++) {
halfEdges[i] = mesh.halfEdges.insert(mesh.halfEdges.end(), HalfEdge());
}
// initialize the halfedges
for (int i = 0; i < n; i++) {
// vertex indices
int a = (*f)[i].position;
int b = (*f)[(i+1)%n].position;
// set halfedge attributes
halfEdges[i]->next = halfEdges[(i+1)%n];
halfEdges[i]->vertex = indexToVertex[a];
int uv = (*f)[i].uv;
if (uv >= 0) halfEdges[i]->uv = data.uvs[uv];
else halfEdges[i]->uv.setZero();
int normal = (*f)[i].normal;
if (normal >= 0) halfEdges[i]->normal = data.normals[normal];
else halfEdges[i]->normal.setZero();
halfEdges[i]->onBoundary = false;
// keep track of which halfedges have flip edges defined (for deteting boundaries)
hasFlipEdge[halfEdges[i]] = false;
// point vertex a at the current halfedge
indexToVertex[a]->he = halfEdges[i];
// point new face and halfedge to each other
halfEdges[i]->face = newFace;
newFace->he = halfEdges[i];
// if an edge between a and b has been created in the past, it is the flip edge of the current halfedge
if (a > b) std::swap(a, b);
if (existingHalfEdges.find(std::pair<int, int>(a, b)) != existingHalfEdges.end()) {
halfEdges[i]->flip = existingHalfEdges[std::pair<int, int>(a, b)];
halfEdges[i]->flip->flip = halfEdges[i];
halfEdges[i]->edge = halfEdges[i]->flip->edge;
hasFlipEdge[halfEdges[i]] = true;
hasFlipEdge[halfEdges[i]->flip] = true;
} else {
// create an edge and set its halfedge
halfEdges[i]->edge = mesh.edges.insert(mesh.edges.end(), Edge());
halfEdges[i]->edge->he = halfEdges[i];
edgeCount[std::pair<int, int>(a, b)] = 0;
}
// record that halfedge has been created from a to b
existingHalfEdges[std::pair<int, int>(a, b)] = halfEdges[i];
// check for nonmanifold edges
edgeCount[std::pair<int, int>(a, b)] ++;
if (edgeCount[std::pair<int, int>(a, b)] > 2) {
std::cerr << "Error: edge " << a << ", " << b << " is non manifold" << std::endl;
return false;
}
}
faceIndex++;
}
if (degenerateFaces) {
return false;
}
// insert extra faces for boundary cycle
for (HalfEdgeIter currHe = mesh.halfEdges.begin(); currHe != mesh.halfEdges.end(); currHe++) {
// if a halfedge with no flip edge is found, create a new face and link it the corresponding boundary cycle
if (!hasFlipEdge[currHe]) {
// create face
FaceIter newFace = mesh.faces.insert(mesh.faces.end(), Face());
// walk along boundary cycle
std::vector<HalfEdgeIter> boundaryCycle;
HalfEdgeIter he = currHe;
do {
// create a new halfedge on the boundary face
HalfEdgeIter newHe = mesh.halfEdges.insert(mesh.halfEdges.end(), HalfEdge());
newHe->onBoundary = true;
// link the current halfedge in the cycle to its new flip edge
he->flip = newHe;
// grab the next halfedge along the boundary by finding
// the next halfedge around the current vertex that doesn't
// have a flip edge defined
HalfEdgeIter nextHe = he->next;
while (hasFlipEdge[nextHe]) {
nextHe = nextHe->flip->next;
}
// set attritubes for new halfedge
newHe->flip = he;
newHe->vertex = nextHe->vertex;
newHe->edge = he->edge;
newHe->face = newFace;
newHe->uv = nextHe->uv;
// set face's halfedge to boundary halfedge
newFace->he = newHe;
boundaryCycle.push_back(newHe);
// continue walk along cycle
he = nextHe;
} while (he != currHe);
// link the cycle of boundary halfedges together
int n = (int)boundaryCycle.size();
for (int i = 0; i < n; i++) {
boundaryCycle[i]->next = boundaryCycle[(i+n-1)%n];
hasFlipEdge[boundaryCycle[i]] = true;
hasFlipEdge[boundaryCycle[i]->flip] = true;
}
mesh.boundaries.insert(mesh.boundaries.end(), boundaryCycle[0]);
}
}
indexVertices(mesh);
checkIsolatedVertices(mesh);
checkNonManifoldVertices(mesh);
return true;
}
