private void MainLoop()
{
int count = 0;
while (faceQueue.Count > 0)
{
count++;
HullFace face = faceQueue.Dequeue();
if (face.active == false)
{
continue;
}
if (face.furthestIndex != -1)
{
int p0 = face.furthestIndex;
this.hullVertices.Add(p0);
// collect visible faces, boundary edges and assoicated vertices
List <HullFace> holeFace = new List <HullFace>();
HashSet <EdgeRecord> holeBoundary = new HashSet <EdgeRecord>();
HashSet <int> assoicatedVertex = new HashSet <int>();
foreach (HullFace f in this.surfaceSet)
{
Vector3d v = this.p[p0] - this.p[f.p1];
if (v.Dot(f.normal) > 0)
{
holeFace.Add(f);
int p1 = f.p1;
int p2 = f.p2;
int p3 = f.p3;
EdgeRecord r1 = new EdgeRecord(p1, p2);
EdgeRecord r2 = new EdgeRecord(p2, p3);
EdgeRecord r3 = new EdgeRecord(p3, p1);
if (holeBoundary.Contains(r1))
{
holeBoundary.Remove(r1);
}
else
{
holeBoundary.Add(r1);
}
if (holeBoundary.Contains(r2))
{
holeBoundary.Remove(r2);
}
else
{
holeBoundary.Add(r2);
}
if (holeBoundary.Contains(r3))
{
holeBoundary.Remove(r3);
}
else
{
holeBoundary.Add(r3);
}
foreach (int index in f.associatedPoints)
{
assoicatedVertex.Add(index);
}
}
}
if (holeFace.Count == 0)
{
throw new Exception();
}
// remove add visible faces
foreach (HullFace f in holeFace)
{
this.surfaceSet.Remove(f);
f.active = false;
}
// add new faces
foreach (EdgeRecord edge in holeBoundary)
{
HullFace newFace = new HullFace(p0, edge.p1, edge.p2);
newFace.normal = ((p[edge.p1] - p[p0]).Cross(p[edge.p2] - p[p0])).normalize();
this.surfaceSet.Add(newFace);
this.faceQueue.Enqueue(newFace);
// add assoicated vertices
foreach (int index in assoicatedVertex)
{
if (index == p0)
{
continue;
}
double dis = (p[index] - p[p0]).Dot(newFace.normal);
if (dis > 0)
{
newFace.AddPoint(index, dis);
}
}
}
}
}
computeCenter();
}
private void InitHullFaces()
{
// get init points
int[] initPts = FindInitPoints();
this.initIndex = initPts;
int p0 = initPts[0];
int p1 = initPts[1];
int p2 = initPts[2];
int p3 = initPts[3];
double vol = (p[p1] - p[p0]).Dot((p[p2] - p[p0]).Cross(p[p3] - p[p0]));
if (vol > 0)
{
int t = p0; p0 = p1; p1 = t;
}
this.hullVertices.Add(p0);
this.hullVertices.Add(p1);
this.hullVertices.Add(p2);
this.hullVertices.Add(p3);
// create hull faces
HullFace f1 = new HullFace(p0, p1, p2); this.faceQueue.Enqueue(f1);
HullFace f2 = new HullFace(p3, p1, p0); this.faceQueue.Enqueue(f2);
HullFace f3 = new HullFace(p3, p2, p1); this.faceQueue.Enqueue(f3);
HullFace f4 = new HullFace(p3, p0, p2); this.faceQueue.Enqueue(f4);
f1.normal = ((p[p1] - p[p0]).Cross(p[p2] - p[p0])).normalize();
f2.normal = ((p[p1] - p[p3]).Cross(p[p0] - p[p3])).normalize();
f3.normal = ((p[p2] - p[p3]).Cross(p[p1] - p[p3])).normalize();
f4.normal = ((p[p0] - p[p3]).Cross(p[p2] - p[p3])).normalize();
this.surfaceSet.Add(f1);
this.surfaceSet.Add(f2);
this.surfaceSet.Add(f3);
this.surfaceSet.Add(f4);
// assoicate vertices outside current hull
foreach (int i in this.pointIndex)
{
if (i == p0 || i == p1 || i == p2 || i == p3)
{
continue;
}
double d1 = (p[i] - p[p0]).Dot(f1.normal);
double d2 = (p[i] - p[p3]).Dot(f2.normal);
double d3 = (p[i] - p[p3]).Dot(f3.normal);
double d4 = (p[i] - p[p3]).Dot(f4.normal);
if (d1 < 0 && d2 < 0 && d3 < 0 && d4 < 0)
{
continue;
}
if (d1 > 0)
{
f1.AddPoint(i, d1);
}
if (d2 > 0)
{
f2.AddPoint(i, d2);
}
if (d3 > 0)
{
f3.AddPoint(i, d3);
}
if (d4 > 0)
{
f4.AddPoint(i, d4);
}
}
}