private static void SetPrevAndNextToExistingHalfEdge(BoundaryEdge bEdge, int existingHeHandle,
IList <BoundaryEdge> boundaryEdges, ICollection <HalfEdge> halfEdgesToUpdate)
{
var existingHe = _geometry.GetHalfEdgeByHandle(existingHeHandle);
var existingHeNext = _geometry.GetHalfEdgeByHandle(existingHe.NextHalfEdge);
var existingHePrev = _geometry.GetHalfEdgeByHandle(existingHe.PrevHalfEdge);
existingHe.NextHalfEdge = bEdge.HalfEdge.NextHalfEdge;
existingHe.PrevHalfEdge = bEdge.HalfEdge.PrevHalfEdge;
existingHe.IncidentFace = bEdge.HalfEdge.IncidentFace;
for (var j = 0; j < boundaryEdges.Count; j++)
{
var count = 0;
var be = boundaryEdges[j];
if (be.TwinHalfEdge.Handle == bEdge.TwinHalfEdge.PrevHalfEdge)
{
var twinHalfEdge = be.TwinHalfEdge;
twinHalfEdge.NextHalfEdge = existingHeNext.Handle;
var halfEdge = be.HalfEdge;
halfEdge.PrevHalfEdge = existingHeHandle;
be.TwinHalfEdge = twinHalfEdge;
be.HalfEdge = halfEdge;
existingHeNext.PrevHalfEdge = twinHalfEdge.Handle;
halfEdgesToUpdate.Add(existingHeNext);
boundaryEdges[j] = be;
count++;
}
if (be.TwinHalfEdge.Handle == bEdge.TwinHalfEdge.NextHalfEdge)
{
var twinHalfEdge = be.TwinHalfEdge;
twinHalfEdge.PrevHalfEdge = existingHePrev.Handle;
var halfEdge = be.HalfEdge;
halfEdge.NextHalfEdge = existingHeHandle;
be.TwinHalfEdge = twinHalfEdge;
be.HalfEdge = halfEdge;
existingHePrev.NextHalfEdge = twinHalfEdge.Handle;
halfEdgesToUpdate.Add(existingHePrev);
boundaryEdges[j] = be;
count++;
}
if (count == 2)
{
break;
}
}
}
private static List <BoundaryEdge> BoundaryEdges(IList <KeyValuePair <Vertex, bool> > outlineVerts,
PolyBoundary polyBoundary)
{
var faceHandle = new int();
var boundaryEdges = new List <BoundaryEdge>();
var halfEdgeHandle = 0;
if (_geometry.DictHalfEdges.Count != 0)
{
halfEdgeHandle = _geometry.DictHalfEdges.Count;
}
for (var j = 0; j < outlineVerts.Count; j++)
{
var currentVert = outlineVerts[j];
halfEdgeHandle++;
if (!currentVert.Value)
{
//Only necessary for new vertices.
var vert = currentVert.Key;
vert.IncidentHalfEdge = halfEdgeHandle;
_geometry.DictVertices.Add(vert.Handle, vert);
}
var halfEdge = new HalfEdge(halfEdgeHandle, currentVert.Key.Handle);
halfEdgeHandle++;
var twinHalfEdge = new HalfEdge(halfEdgeHandle, outlineVerts[(j + 1) % outlineVerts.Count].Key.Handle,
halfEdge.Handle, 0, 0, 1);
//The unbounded face is always added at first and therefor has 1 as handle.
halfEdge.TwinHalfEdge = twinHalfEdge.Handle;
//Assumption: outlines are processed from outer to inner, therefore faceHandle will never has its default value if "else" is hit.
if (polyBoundary.IsOuter)
{
if (faceHandle == default(int))
{
Face face;
faceHandle = AddFace(halfEdge.Handle, out face);
_geometry.DictFaces.Add(face.Handle, face);
}
}
else
{
if (j == 0)
{
var lastFace = _geometry.DictFaces[_geometry.DictFaces.Keys.Max()];
lastFace.InnerHalfEdges.Add(halfEdge.Handle);
}
faceHandle = _geometry.DictFaces.Last().Value.Handle;
}
halfEdge.IncidentFace = faceHandle;
if (!outlineVerts[j].Value)
{
var unboundFace = _geometry.DictFaces[1];
if (j == 0)
{
unboundFace.InnerHalfEdges.Add(twinHalfEdge.Handle);
_geometry.DictFaces[1] = unboundFace;
}
}
var boundaryEdge = new BoundaryEdge
{
IsOriginOldVert = currentVert.Value,
HalfEdge = halfEdge,
TwinHalfEdge = twinHalfEdge
};
boundaryEdges.Add(boundaryEdge);
}
return(boundaryEdges);
}
