bool ICHull::CleanVertices(unsigned int& addedPoints)
{
// mark all vertices incident to some undeleted edge as on the hull
CircularList<TMMEdge>& edges = m_mesh.GetEdges();
CircularListElement<TMMEdge>* e = edges.GetHead();
size_t nE = edges.GetSize();
for (size_t i = 0; i < nE; i++) {
e->GetData().m_vertices[0]->GetData().m_onHull = true;
e->GetData().m_vertices[1]->GetData().m_onHull = true;
e = e->GetNext();
}
// delete all the vertices that have been processed but are not on the hull
CircularList<TMMVertex>& vertices = m_mesh.GetVertices();
CircularListElement<TMMVertex>* vHead = vertices.GetHead();
CircularListElement<TMMVertex>* v = vHead;
v = v->GetPrev();
do {
if (v->GetData().m_tag && !v->GetData().m_onHull) {
CircularListElement<TMMVertex>* tmp = v->GetPrev();
vertices.Delete(v);
v = tmp;
addedPoints--;
}
else {
v->GetData().m_duplicate = 0;
v->GetData().m_onHull = false;
v = v->GetPrev();
}
} while (v->GetData().m_tag && v != vHead);
return true;
}
bool ICHull::ProcessPoint()
{
double totalVolume = 0.0;
if (!ComputePointVolume(totalVolume, true)) {
return false;
}
// Mark edges in interior of visible region for deletion.
// Create a new face based on each border edge
CircularListElement<TMMVertex>* v0 = m_mesh.GetVertices().GetHead();
CircularListElement<TMMEdge>* eHead = m_mesh.GetEdges().GetHead();
CircularListElement<TMMEdge>* e = eHead;
CircularListElement<TMMEdge>* tmp = 0;
int nvisible = 0;
m_edgesToDelete.Resize(0);
m_edgesToUpdate.Resize(0);
do {
tmp = e->GetNext();
nvisible = 0;
for (int k = 0; k < 2; k++) {
if (e->GetData().m_triangles[k]->GetData().m_visible) {
nvisible++;
}
}
if (nvisible == 2) {
m_edgesToDelete.PushBack(e);
}
else if (nvisible == 1) {
e->GetData().m_newFace = MakeConeFace(e, v0);
m_edgesToUpdate.PushBack(e);
}
e = tmp;
} while (e != eHead);
return true;
}
bool ICHull::FindMaxVolumePoint(const double minVolume)
{
CircularList<TMMVertex>& vertices = m_mesh.GetVertices();
CircularListElement<TMMVertex>* vMaxVolume = 0;
CircularListElement<TMMVertex>* vHeadPrev = vertices.GetHead()->GetPrev();
double maxVolume = minVolume;
double volume = 0.0;
while (!vertices.GetData().m_tag) // not processed
{
if (ComputePointVolume(volume, false)) {
if (maxVolume < volume) {
maxVolume = volume;
vMaxVolume = vertices.GetHead();
}
vertices.Next();
}
}
CircularListElement<TMMVertex>* vHead = vHeadPrev->GetNext();
vertices.GetHead() = vHead;
if (!vMaxVolume) {
return false;
}
if (vMaxVolume != vHead) {
Vec3<double> pos = vHead->GetData().m_pos;
int id = vHead->GetData().m_name;
vHead->GetData().m_pos = vMaxVolume->GetData().m_pos;
vHead->GetData().m_name = vMaxVolume->GetData().m_name;
vMaxVolume->GetData().m_pos = pos;
vHead->GetData().m_name = id;
}
return true;
}
bool ICHull::ComputePointVolume(double& totalVolume, bool markVisibleFaces)
{
// mark visible faces
CircularListElement<TMMTriangle>* fHead = m_mesh.GetTriangles().GetHead();
CircularListElement<TMMTriangle>* f = fHead;
CircularList<TMMVertex>& vertices = m_mesh.GetVertices();
CircularListElement<TMMVertex>* vertex0 = vertices.GetHead();
bool visible = false;
Vec3<double> pos0 = Vec3<double>(vertex0->GetData().m_pos.X(),
vertex0->GetData().m_pos.Y(),
vertex0->GetData().m_pos.Z());
double vol = 0.0;
totalVolume = 0.0;
Vec3<double> ver0, ver1, ver2;
do
{
ver0.X() = f->GetData().m_vertices[0]->GetData().m_pos.X();
ver0.Y() = f->GetData().m_vertices[0]->GetData().m_pos.Y();
ver0.Z() = f->GetData().m_vertices[0]->GetData().m_pos.Z();
ver1.X() = f->GetData().m_vertices[1]->GetData().m_pos.X();
ver1.Y() = f->GetData().m_vertices[1]->GetData().m_pos.Y();
ver1.Z() = f->GetData().m_vertices[1]->GetData().m_pos.Z();
ver2.X() = f->GetData().m_vertices[2]->GetData().m_pos.X();
ver2.Y() = f->GetData().m_vertices[2]->GetData().m_pos.Y();
ver2.Z() = f->GetData().m_vertices[2]->GetData().m_pos.Z();
vol = ComputeVolume4(ver0, ver1, ver2, pos0);
if (vol < -sc_eps)
{
vol = fabs(vol);
totalVolume += vol;
if (markVisibleFaces)
{
f->GetData().m_visible = true;
m_trianglesToDelete.PushBack(f);
}
visible = true;
}
f = f->GetNext();
} while (f != fHead);
if (m_trianglesToDelete.Size() == m_mesh.m_triangles.GetSize())
{
for (size_t i = 0; i < m_trianglesToDelete.Size(); i++)
{
m_trianglesToDelete[i]->GetData().m_visible = false;
}
visible = false;
}
// if no faces visible from p then p is inside the hull
if (!visible && markVisibleFaces)
{
vertices.Delete();
m_trianglesToDelete.Resize(0);
return false;
}
return true;
}
ICHullError ICHull::DoubleTriangle()
{
// find three non colinear points
m_isFlat = false;
CircularList<TMMVertex>& vertices = m_mesh.GetVertices();
CircularListElement<TMMVertex>* v0 = vertices.GetHead();
while (Colinear(v0->GetData().m_pos,
v0->GetNext()->GetData().m_pos,
v0->GetNext()->GetNext()->GetData().m_pos)) {
if ((v0 = v0->GetNext()) == vertices.GetHead()) {
return ICHullErrorCoplanarPoints;
}
}
CircularListElement<TMMVertex>* v1 = v0->GetNext();
CircularListElement<TMMVertex>* v2 = v1->GetNext();
// mark points as processed
v0->GetData().m_tag = v1->GetData().m_tag = v2->GetData().m_tag = true;
// create two triangles
CircularListElement<TMMTriangle>* f0 = MakeFace(v0, v1, v2, 0);
MakeFace(v2, v1, v0, f0);
// find a fourth non-coplanar point to form tetrahedron
CircularListElement<TMMVertex>* v3 = v2->GetNext();
vertices.GetHead() = v3;
double vol = ComputeVolume4(v0->GetData().m_pos, v1->GetData().m_pos, v2->GetData().m_pos, v3->GetData().m_pos);
while (fabs(vol) < sc_eps && !v3->GetNext()->GetData().m_tag) {
v3 = v3->GetNext();
vol = ComputeVolume4(v0->GetData().m_pos, v1->GetData().m_pos, v2->GetData().m_pos, v3->GetData().m_pos);
}
if (fabs(vol) < sc_eps) {
// compute the barycenter
Vec3<double> bary(0.0, 0.0, 0.0);
CircularListElement<TMMVertex>* vBary = v0;
do {
bary += vBary->GetData().m_pos;
} while ((vBary = vBary->GetNext()) != v0);
bary /= static_cast<double>(vertices.GetSize());
// Compute the normal to the plane
Vec3<double> p0 = v0->GetData().m_pos;
Vec3<double> p1 = v1->GetData().m_pos;
Vec3<double> p2 = v2->GetData().m_pos;
m_normal = (p1 - p0) ^ (p2 - p0);
m_normal.Normalize();
// add dummy vertex placed at (bary + normal)
vertices.GetHead() = v2;
Vec3<double> newPt = bary + m_normal;
AddPoint(newPt, sc_dummyIndex);
m_isFlat = true;
return ICHullErrorOK;
}
else if (v3 != vertices.GetHead()) {
TMMVertex temp;
temp.m_name = v3->GetData().m_name;
temp.m_pos = v3->GetData().m_pos;
v3->GetData().m_name = vertices.GetHead()->GetData().m_name;
v3->GetData().m_pos = vertices.GetHead()->GetData().m_pos;
vertices.GetHead()->GetData().m_name = temp.m_name;
vertices.GetHead()->GetData().m_pos = temp.m_pos;
}
return ICHullErrorOK;
}