public static HalfEdgeMesh Subdivide(HalfEdgeMesh mesh)
{
HalfEdgeMesh nextLevelMesh = new HalfEdgeMesh();
foreach (HE_Face face in mesh.faces)
{
Vector3[] next_edge_positions = new Vector3[3];
Vector3[] next_vert_positions = new Vector3[3];
{
int count = 0;
HE_Edge edge = face.edge_;
do
{
if (edge.pair_ != null)
{
next_edge_positions[count] =
edge.vert_.pos_ * 0.375f +
edge.next_.vert_.pos_ * 0.375f +
edge.prev_.vert_.pos_ * 0.125f +
edge.pair_.prev_.vert_.pos_ * 0.125f;
}
else
{
next_edge_positions[count] =
edge.vert_.pos_ * 0.5f +
edge.next_.vert_.pos_ * 0.5f;
}
{
List <HE_Vertex> neighbors;
edge.vert_.GetNeighboringVertices(out neighbors);
int n = neighbors.Count;
float beta = n > 3 ? 3.0f / (8.0f * n) : 3.0f / 16.0f;
next_vert_positions[count] = (1 - n * beta) * edge.vert_.pos_;
for (int k = 0; k < n; ++k)
{
next_vert_positions[count] += neighbors[k].pos_ * beta;
}
}
++count;
edge = edge.next_;
} while (!edge.Equals(face.edge_) && count < 3);
}
{
for (int k = 0; k < 3; ++k)
{
int prev_k = (k + 2) % 3;
Vector3[] next_face =
{
next_vert_positions[k],
next_edge_positions[k],
next_edge_positions[prev_k]
};
nextLevelMesh.AddFace(next_face);
}
Vector3[] next_face_second = { next_edge_positions[0], next_edge_positions[1], next_edge_positions[2] };
nextLevelMesh.AddFace(next_face_second);
}
}
nextLevelMesh.SolveAllPairs();
return(nextLevelMesh);
}
