public void Subdivision()
{
/* /\ /\
* / \ /__\
* / \ /\ /\
* / \ /__\/__\
* / \ /\ /\ /\
* /__________\ /__\/__\/__\
*
* 为了让每个顶点周围都有它专属的一圈价为6的点，把每个三角形拆成9个
*/
TriMesh copy = TriMeshIO.Clone(this.mesh);
this.mesh.Clear();
TriMesh.Vertex[] faceMap = new HalfEdgeMesh.Vertex[copy.Faces.Count];
TriMesh.Vertex[] hfMap = new HalfEdgeMesh.Vertex[copy.HalfEdges.Count];
foreach (var v in copy.Vertices)
{
this.mesh.Vertices.Add(new VertexTraits(v.Traits.Position));
}
foreach (var face in copy.Faces)
{
faceMap[face.Index] = this.mesh.Vertices.Add(new VertexTraits(TriMeshUtil.GetMidPoint(face)));
}
foreach (var hf in copy.HalfEdges)
{
Vector3D pos = hf.FromVertex.Traits.Position * 2 / 3 + hf.ToVertex.Traits.Position * 1 / 3;
hfMap[hf.Index] = this.mesh.Vertices.Add(new VertexTraits(pos));
}
foreach (var face in copy.Faces)
{
foreach (var hf in face.Halfedges)
{
this.mesh.Faces.AddTriangles(faceMap[face.Index], hfMap[hf.Index], hfMap[hf.Opposite.Index]);
this.mesh.Faces.AddTriangles(faceMap[face.Index], hfMap[hf.Opposite.Index], hfMap[hf.Next.Index]);
}
}
foreach (var v in copy.Vertices)
{
foreach (var hf in v.HalfEdges)
{
if (hf.Face != null)
{
this.mesh.Faces.AddTriangles(this.mesh.Vertices[v.Index], hfMap[hf.Index], hfMap[hf.Previous.Opposite.Index]);
}
}
}
}
