public HalfEdge GetEdge(Vertex a, Vertex b, Face f, HalfEdge abNext)
{
List<HalfEdge> appropriateEdges;
if (edges.ContainsKey(b))
{
appropriateEdges = edges[b];
}
else
{
appropriateEdges = new List<HalfEdge>();
edges[b] = appropriateEdges;
}
var query = appropriateEdges.Where(x => x.Twin.End == a);
switch (query.Count())
{
case 0:
{
HalfEdge edge = new HalfEdge(this, null, true);
HalfEdge twin = edge.Twin;
edge.End = b;
twin.End = a;
edge.Face = f;
edge.Next = abNext;
return edge;
}
case 1:
{
var edge = query.First();
if (abNext != null && edge.Next != abNext && edge.Next != null)
throw new ArgumentException("Edge already attached to edge " + edge.Next);
if (f != null && edge.Face != f && edge.Face != null)
throw new ArgumentException("Edge already attached to face " + edge.Face);
edge.Face = f ?? edge.Face;
edge.Next = abNext ?? edge.Next;
return edge;
}
default:
throw new MeshMalformedException("More than one edge already exists between " + a + " and " + b);
}
}
private IEnumerable<ProceduralFace> Split(Face f)
{
HashSet<HalfEdge> edges = new HashSet<HalfEdge>();
foreach (var edge in f.Edges)
{
var dir = (edge.End.Position - edge.Twin.End.Position);
if (Math.Abs(dir.X) > 0.1f || Math.Abs(dir.Z) > 0.1f)
edges.Add(edge);
}
if (edges.Count != 2)
throw new InvalidOperationException("Not 2 edges");
int splits = 2;
foreach (var edge in edges)
{
var dir = edge.End.Position - edge.Twin.End.Position;
var step = dir / (float)splits;
var start = edge.Twin.End.Position;
for (int i = 1; i < splits; i++)
edge.Split(Mesh.GetVertex(start + step * i));
}
Vertex[] vertices = f.Vertices.ToArray();
f.Delete();
for (int i = 0; i < vertices.Length / 2 - 1; i++)
{
yield return (ProceduralFace)Mesh.GetFace(vertices[i], vertices[i + 1], vertices[vertices.Length - 2 - i], vertices[vertices.Length - 1 - i]);
}
//return new List<ProceduralFace>();
}
private IEnumerable<ProceduralFace> Split(Face f)
{
Vertex[] v = f.Vertices.ToArray();
f.Delete();
Vector3 up = -new Plane(v[0].Position, v[1].Position, v[2].Position).Normal;
Vertex a = Mesh.GetVertex(v[0].Position * 0.5f + v[1].Position * 0.5f + up * 2);
Vertex b = Mesh.GetVertex(v[2].Position * 0.5f + v[3].Position * 0.5f + up * 2);
yield return (ProceduralFace)Mesh.GetFace(v[1], v[2], b, a);
yield return (ProceduralFace)Mesh.GetFace(v[3], v[0], a, b);
yield return (ProceduralFace)Mesh.GetFace(v[0], v[1], a);
yield return (ProceduralFace)Mesh.GetFace(v[2], v[3], b);
}
public void Deleted(Face f)
{
changes.Push(new DeleteFace(f));
}
public void Added(Face f)
{
changes.Push(new AddFace(f));
}
public DeleteFace(Face f)
{
Border = f.Vertices.Select(a => a.Position).ToArray();
}
public AddFace(Face f)
{
Border = f.Vertices.ToArray();
}
public void SplitMidpointEnd(Face f, Vertex mid)
{
throw new NotImplementedException();
}
public Face GetFace(IEnumerable<Vertex> vertices)
{
//throw new NotImplementedException("Check if this face already exists");
//throw new NotImplementedException("Check if this face would conflict with an already existing face");
List<HalfEdge> edges = new List<HalfEdge>();
Face f = new Face();
Vertex first = null;
Vertex previous = null;
foreach (var v in vertices)
{
if (first == null)
first = v;
else
edges.Add(GetEdge(previous, v, f, null));
previous = v;
}
edges.Add(GetEdge(previous, first, f, null));
for (int i = 0; i < edges.Count; i++)
{
var next = edges[(i + 1) % edges.Count];
if (edges[i].Next != null && edges[i].Next != next)
throw new InvalidOperationException("Cannot link edges, conflicting link already exists");
edges[i].Next = edges[(i + 1) % edges.Count];
}
foreach (var vertex in vertices)
{
var set = faces.GetOrAdd(vertex, a => new ConcurrentDictionary<Face, bool>());
set.AddOrUpdate(f, true, (a, b) => { throw new InvalidOperationException(); });
}
return f;
}
public HalfEdge GetEdge(Vertex a, Vertex b, Face abf, HalfEdge abNext, Face baf, HalfEdge baNext)
{
throw new NotImplementedException();
}
