void CleanUpMesh()
{
int numInvalidFaces = 0;
int numInvalidEdges = 0;
int numInvalidVertices = 0;
int numInvalidHalfEdges = 0;
List <HalfEdge> newHalfEdges = new List <HalfEdge>();
List <Face> newFaces = new List <Face>();
List <Edge> newEdges = new List <Edge>();
List <Vertex> newVertices = new List <Vertex>();
foreach (HalfEdge he in halfEdges)
{
if (he.Valid)
{
newHalfEdges.Add(he);
}
else
{
numInvalidHalfEdges++;
}
}
foreach (Face f in faces)
{
if (f.Valid)
{
newFaces.Add(f);
}
else
{
numInvalidFaces++;
}
}
foreach (Edge e in edges)
{
if (e.Valid)
{
newEdges.Add(e);
}
else
{
numInvalidEdges++;
}
}
foreach (Vertex v in vertices)
{
if (v.Valid)
{
newVertices.Add(v);
}
else
{
numInvalidVertices++;
}
}
halfEdges = newHalfEdges.ToArray();
faces = newFaces.ToArray();
edges = newEdges.ToArray();
vertices = newVertices.ToArray();
Debug.Log(numInvalidHalfEdges + " invalid half-edges, " +
numInvalidVertices + " invalid vertices, " +
numInvalidEdges + " invalid edges, " +
numInvalidFaces + " invalid faces");
TagIndices();
Vector3[] positions = new Vector3[vertices.Length];
for (int i = 0; i < positions.Length; i++)
{
positions[i] = vertices[i].position;
}
Debug.Log(positions.Length + " vertices left");
int maxIndex = 0;
List <int> triangles = new List <int>();
foreach (Face f in faces)
{
if (f.IsBoundary)
{
continue;
}
HalfEdge he = f.anyHalfEdge;
for (int i = 0; i < 3; i++)
{
triangles.Add(he.tailVertex.Index);
maxIndex = Mathf.Max(maxIndex, he.tailVertex.Index);
he = he.next;
}
}
Debug.Log("Max triangle index = " + maxIndex);
targetMesh.mesh.triangles = triangles.ToArray();
targetMesh.mesh.vertices = positions;
}
public void CollapseEdge(Edge e)
{
if (!e.Valid)
{
return;
}
HalfEdge nearSide = e.anyHalfEdge;
HalfEdge farSide = nearSide.flip;
// Assign all half-edge tails to one of the vertices.
Vertex keepVertex = nearSide.tailVertex;
Vertex discardVertex = farSide.tailVertex;
HalfEdge start = discardVertex.anyHalfEdge;
HalfEdge he = start;
Debug.Log("Reassigning tails from " + discardVertex.Index + " (" + discardVertex.Valid + ") to "
+ keepVertex.Index + " (" + keepVertex.Valid + ")");
do
{
if (!he.Valid)
{
throw new System.Exception("Invalid half-edge reached");
}
if (he.tailVertex != discardVertex)
{
throw new System.Exception("Tail vertex changed to "
+ he.tailVertex.Index);
}
he.tailVertex = keepVertex;
he = he.flip.next;
}while (he != start);
// Reassign the vertex's half-edge pointer, because the current
// one may become invalid if it is the collapsed edge.
// Search for a half-edge not in either of the faces that will be collapsed.
while (keepVertex.anyHalfEdge.face == nearSide.face ||
keepVertex.anyHalfEdge.face == farSide.face)
{
keepVertex.anyHalfEdge = keepVertex.anyHalfEdge.flip.next;
if (keepVertex.anyHalfEdge == nearSide)
{
Debug.Log("Cycled around; no possible valid edges near vertex " + keepVertex.Index);
}
}
// Add the merged vertex and all of its merged vertices to the
// list of identified vertices.
keepVertex.IdenticalVertices.AddRange(discardVertex.IdenticalVertices);
keepVertex.IdenticalVertices.Add(discardVertex);
// Invalidate the other vertex.
discardVertex.Valid = false;
Debug.Log("Collapsing triangles");
// Collapse triangles on both sides.
CollapseTriangle(nearSide);
CollapseTriangle(farSide);
// Finally edit the positions of the merged vertices.
Vector3 midpoint = (keepVertex.position + discardVertex.position) / 2;
keepVertex.position = midpoint;
discardVertex.position = midpoint;
}