public static PolygonMesh BuildDual(TriMesh mesh, EnumDual type)
{
TriMeshModify.RepaireAllHole(mesh);
PolygonMesh.Vertex[] faceMap = new HalfEdgeMesh.Vertex[mesh.Faces.Count];
PolygonMesh.Vertex[] edgeMap = new HalfEdgeMesh.Vertex[mesh.Edges.Count];
PolygonMesh pm = new PolygonMesh();
foreach (var face in mesh.Faces)
{
Vector3D center = Vector3D.Zero;
switch (type)
{
case EnumDual.DualA:
center = TriMeshUtil.GetMidPoint(face);
break;
case EnumDual.DualB:
TriMesh.Vertex vertex0 = face.GetVertex(0);
TriMesh.Vertex vertex1 = face.GetVertex(1);
TriMesh.Vertex vertex2 = face.GetVertex(2);
Triangle triangle = new Triangle(vertex0.Traits.Position,
vertex1.Traits.Position,
vertex2.Traits.Position);
center = triangle.ComputeCircumCenter();
break;
default:
break;
}
PolygonMesh.Vertex v = new HalfEdgeMesh.Vertex(new VertexTraits(center));
faceMap[face.Index] = v;
pm.AppendToVertexList(v);
}
foreach (var edge in mesh.Edges)
{
VertexTraits trait = new VertexTraits(TriMeshUtil.GetMidPoint(edge));
PolygonMesh.Vertex v = new HalfEdgeMesh.Vertex(trait);
edgeMap[edge.Index] = v;
pm.AppendToVertexList(v);
}
foreach (var v in mesh.Vertices)
{
List<PolygonMesh.Vertex> list = new List<HalfEdgeMesh.Vertex>();
foreach (var hf in v.HalfEdges)
{
list.Add(faceMap[hf.Face.Index]);
list.Add(edgeMap[hf.Edge.Index]);
}
list.Reverse();
pm.Faces.Add(list.ToArray());
}
return pm;
}
public void ComputeGeometryC(PolygonMesh dualMesh)
{
//get the mid-Vertex of each edges
TriMesh.Vertex[] edgeVertices = new TriMesh.Vertex[mesh.Faces.Count * 3];
foreach (TriMesh.Edge e in mesh.Edges)
{
Vector3D midVertex0 = TriMeshUtil.GetMidPoint(e);
dualMesh.Vertices.Add(new VertexTraits(midVertex0.x,
midVertex0.y,
midVertex0.z));
}
//get circumcentre of each faces
foreach (TriMesh.Face f in mesh.Faces)
{
TriMesh.Vertex vertex0 = f.GetVertex(0);
TriMesh.Vertex vertex1 = f.GetVertex(1);
TriMesh.Vertex vertex2 = f.GetVertex(2);
Triangle triangle = new Triangle(vertex0.Traits.Position, vertex1.Traits.Position, vertex2.Traits.Position);
Vector3D circumCenter = triangle.ComputeCircumCenter();
dualMesh.Vertices.Add(new VertexTraits(circumCenter.x,
circumCenter.y,
circumCenter.z));
}
}
