/// <summary>
/// Initializes a new instance of the <see cref="MeshPoint"/> class.
/// </summary>
/// <param name="point">3D Point.</param>
/// <param name="face">Mesh face.</param>
public MeshPoint(Point3d point, MeshFace face)
{
List <MeshVertex> adj = face.AdjacentVertices();
double[] bary = Convert.Point3dToBarycentric(point, adj[0], adj[1], adj[2]);
U = bary[0];
V = bary[1];
W = bary[2];
}
// Takes a List containing another List per face with the vertex indexes belonging to that face
private bool CreateFaces(List <List <int> > faceIndexes)
{
Dictionary <string, int> edgeCount = new Dictionary <string, int>();
Dictionary <string, MeshHalfEdge> existingHalfEdges = new Dictionary <string, MeshHalfEdge>();
Dictionary <MeshHalfEdge, bool> hasTwinHalfEdge = new Dictionary <MeshHalfEdge, bool>();
// Create the faces, edges and half-edges, non-boundary loops and link references when possible;
foreach (List <int> indexes in faceIndexes)
{
MeshFace f = new MeshFace();
Faces.Add(f);
List <MeshHalfEdge> tempHEdges = new List <MeshHalfEdge>(indexes.Count);
// Create empty half-edges
for (int i = 0; i < indexes.Count; i++)
{
MeshHalfEdge h = new MeshHalfEdge();
tempHEdges.Add(h);
}
// Fill out each half edge
for (int i = 0; i < indexes.Count; i++)
{
// Edge goes from v0 to v1
int v0 = indexes[i];
int v1 = indexes[(i + 1) % indexes.Count];
MeshHalfEdge h = tempHEdges[i];
// Set previous and next
h.Next = tempHEdges[(i + 1) % indexes.Count];
h.Prev = tempHEdges[(i + indexes.Count - 1) % indexes.Count];
h.OnBoundary = false;
hasTwinHalfEdge.Add(h, false);
// Set half-edge & vertex mutually
h.Vertex = Vertices[v0];
Vertices[v0].HalfEdge = h;
// Set half-edge face & vice versa
h.Face = f;
f.HalfEdge = h;
// Reverse v0 and v1 if v0 > v1
if (v0 > v1)
{
int temp = v0;
v0 = v1;
v1 = temp;
}
string key = v0 + " " + v1;
if (existingHalfEdges.ContainsKey(key))
{
// If this half-edge key already exists, it is the twin of this current half-edge
MeshHalfEdge twin = existingHalfEdges[key];
h.Twin = twin;
twin.Twin = h;
h.Edge = twin.Edge;
hasTwinHalfEdge[h] = true;
hasTwinHalfEdge[twin] = true;
edgeCount[key]++;
}
else
{
// Create an edge and set its half-edge
MeshEdge e = new MeshEdge();
Edges.Add(e);
h.Edge = e;
e.HalfEdge = h;
// Record the newly created half-edge
existingHalfEdges.Add(key, h);
edgeCount.Add(key, 1);
}
}
HalfEdges.AddRange(tempHEdges);
}
// Create boundary edges
for (int i = 0; i < HalfEdges.Count; i++)
{
MeshHalfEdge h = HalfEdges[i];
if (!hasTwinHalfEdge[h])
{
MeshFace f = new MeshFace();
Boundaries.Add(f);
List <MeshHalfEdge> boundaryCycle = new List <MeshHalfEdge>();
MeshHalfEdge hE = h;
do
{
MeshHalfEdge bH = new MeshHalfEdge();
HalfEdges.Add(bH);
boundaryCycle.Add(bH);
MeshHalfEdge nextHE = hE.Next;
while (hasTwinHalfEdge[nextHE])
{
nextHE = nextHE.Twin.Next;
}
bH.Vertex = nextHE.Vertex;
bH.Edge = hE.Edge;
bH.OnBoundary = true;
bH.Face = f;
f.HalfEdge = bH;
bH.Twin = hE;
hE.Twin = bH;
hE = nextHE;
}while (hE != h);
int n = boundaryCycle.Count;
for (int j = 0; j < n; j++)
{
boundaryCycle[j].Next = boundaryCycle[(j + n - 1) % n];
boundaryCycle[j].Prev = boundaryCycle[(j + 1) % n];
hasTwinHalfEdge[boundaryCycle[j]] = true;
hasTwinHalfEdge[boundaryCycle[j].Twin] = true;
}
}
if (!h.OnBoundary)
{
MeshCorner corner = new MeshCorner
{
HalfEdge = h,
};
h.Corner = corner;
Corners.Add(corner);
}
}
// Check mesh for common errors
if (HasIsolatedFaces() || HasIsolatedVertices() || HasNonManifoldEdges())
{
return(false);
}
// Index elements
IndexElements();
return(true);
}
