private void CreateTriangleFace(List <Edge> existingEdges, Shape subdivided, Face face)
{
List <Point> points = face.AllPoints;
Point a = points[0].Successor;
Point b = points[1].Successor;
Point c = points[2].Successor;
//for a triangle face (a,b,c):
// (a, edge_pointab, face_pointabc, edge_pointca)
// (b, edge_pointbc, face_pointabc, edge_pointab)
// (c, edge_pointca, face_pointabc, edge_pointbc)
Point facePoint = face.FacePoint;
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, a, face.Edges[0].EdgePoint, face.Edges[2].EdgePoint));
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, b, face.Edges[1].EdgePoint, face.Edges[0].EdgePoint));
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, c, face.Edges[2].EdgePoint, face.Edges[1].EdgePoint));
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, face.Edges[0].EdgePoint, face.Edges[1].EdgePoint, face.Edges[2].EdgePoint));
SubdivisionUtilities.VerifyThatThereAreNoEdgeDuplicates(existingEdges);
}
public Shape BuildBox(double x, double y, double z)
{
Shape shape = new Shape();
Point[,,] points = CreateBoxPoints(x, y, z);
List <Edge> edges = new List <Edge>();
// Using OGRE which uses counter clockwise winding / anti clickwise winding. Our faces are thus CCW.
// http://www.ogre3d.org/docs/api/html/classOgre_1_1ManualObject.html
// This is important for determining frontfacing and backfacing faces.
// Get it wrong and faces become invisible and the manifold is broken.
shape.AddFace(SubdivisionUtilities.CreateFaceF(edges, points[0, 0, 0], points[1, 0, 0], points[1, 0, 1], points[0, 0, 1]));
shape.AddFace(SubdivisionUtilities.CreateFaceR(edges, points[0, 1, 0], points[1, 1, 0], points[1, 1, 1], points[0, 1, 1]));
shape.AddFace(SubdivisionUtilities.CreateFaceF(edges, points[0, 0, 0], points[0, 1, 0], points[1, 1, 0], points[1, 0, 0]));
shape.AddFace(SubdivisionUtilities.CreateFaceR(edges, points[0, 0, 1], points[0, 1, 1], points[1, 1, 1], points[1, 0, 1]));
shape.AddFace(SubdivisionUtilities.CreateFaceR(edges, points[0, 0, 0], points[0, 1, 0], points[0, 1, 1], points[0, 0, 1]));
shape.AddFace(SubdivisionUtilities.CreateFaceR(edges, points[1, 0, 0], points[1, 0, 1], points[1, 1, 1], points[1, 1, 0]));
return(shape);
}
private void CreateFaces(Shape shape, Shape subdivided)
{
List <Face> faces = shape.Faces;
List <Edge> existingEdges = new List <Edge>();
foreach (Face face in faces)
{
if (face.AllPoints.Count() == 3)
{
CreateTriangleFace(existingEdges, subdivided, face);
}
else if (face.AllPoints.Count() == 4)
{
CreateQuadFace(existingEdges, subdivided, face);
}
else
{
throw new InvalidOperationException(string.Format("Unhandled facetype (point count={0})!", face.AllPoints.Count()));
}
}
SubdivisionUtilities.VerifyThatThereAreNoEdgeDuplicates(existingEdges);
}
private void CreateQuadFace(List <Edge> existingEdges, Shape subdivided, Face face)
{
// 0 1 2 -> 3
//for a quad face (a,b,c,d):
// (a, edge_pointab, face_pointabcd, edge_pointda)
// (b, edge_pointbc, face_pointabcd, edge_pointab)
// (c, edge_pointcd, face_pointabcd, edge_pointbc)
// (d, edge_pointda, face_pointabcd, edge_pointcd)
List <Point> points = face.AllPoints;
Point a = points[0].Successor;
Point b = points[1].Successor;
Point c = points[2].Successor;
Point d = points[3].Successor;
Point facePoint = face.FacePoint;
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, a, face.Edges[0].EdgePoint, facePoint, face.Edges[3].EdgePoint));
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, b, face.Edges[1].EdgePoint, facePoint, face.Edges[0].EdgePoint));
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, c, face.Edges[2].EdgePoint, facePoint, face.Edges[1].EdgePoint));
subdivided.Faces.Add(SubdivisionUtilities.CreateFaceF(existingEdges, d, face.Edges[3].EdgePoint, facePoint, face.Edges[2].EdgePoint));
SubdivisionUtilities.VerifyThatThereAreNoEdgeDuplicates(existingEdges);
}