//EDGE VECTOR
/* return the edge vector from a halfedge index pointing from halfedge start towards halfedge end */
public Vector3d edgeVector(PlanktonMesh pMesh, int halfedgeIndex)
{
PlanktonHalfedge pHalfedge = pMesh.Halfedges[halfedgeIndex];
//start vertex
PlanktonVertex pVStart = pMesh.Vertices[pHalfedge.StartVertex];
Point3d startVertex = new Point3d(pVStart.X, pVStart.Y, pVStart.Z);
//end vertex
PlanktonVertex pVEnd = pMesh.Vertices[pMesh.Halfedges[pHalfedge.NextHalfedge].StartVertex];
Point3d endVertex = new Point3d(pVEnd.X, pVEnd.Y, pVEnd.Z);
//edge vector
Vector3d vecEdge = new Vector3d(endVertex - startVertex);
return vecEdge;
}
private void ProcessEdgeLengthConstraint()
{
int halfedgeCount = ptMesh.Halfedges.Count;
for (int k = 0; k < halfedgeCount; k += 2)
{
PlanktonHalfedge halfedge = ptMesh.Halfedges[k];
int i = halfedge.StartVertex;
int j = ptMesh.Halfedges[halfedge.NextHalfedge].StartVertex;
Vector3d d = ptMesh.Vertices[j].ToPoint3d() - ptMesh.Vertices[i].ToPoint3d();
if (d.Length > CollisionDistance)
{
Vector3d move = EdgeLengthConstraintWeight * 0.5 * (d);
totalWeightedMoves[i] += move;
totalWeightedMoves[j] -= move;
totalWeights[i] += EdgeLengthConstraintWeight;
totalWeights[j] += EdgeLengthConstraintWeight;
}
}
}
/// <summary>
/// Creates a Plankton halfedge mesh from a Rhino mesh.
/// Uses the topology of the Rhino mesh directly.
/// </summary>
/// <returns>A <see cref="PlanktonMesh"/> which represents the topology and geometry of the source mesh.</returns>
/// <param name="source">A Rhino mesh to convert from.</param>
public static PlanktonMesh ToPlanktonMesh(this Mesh source)
{
PlanktonMesh pMesh = new PlanktonMesh();
source.Vertices.CombineIdentical(true, true);
source.Vertices.CullUnused();
source.UnifyNormals();
source.Weld(Math.PI);
foreach (Point3f v in source.TopologyVertices)
{
pMesh.Vertices.Add(v.X, v.Y, v.Z);
}
for (int i = 0; i < source.Faces.Count; i++)
{
pMesh.Faces.Add(new PlanktonFace());
}
for (int i = 0; i < source.TopologyEdges.Count; i++)
{
PlanktonHalfedge HalfA = new PlanktonHalfedge();
HalfA.StartVertex = source.TopologyEdges.GetTopologyVertices(i).I;
if (pMesh.Vertices [HalfA.StartVertex].OutgoingHalfedge == -1)
{
pMesh.Vertices [HalfA.StartVertex].OutgoingHalfedge = pMesh.Halfedges.Count;
}
PlanktonHalfedge HalfB = new PlanktonHalfedge();
HalfB.StartVertex = source.TopologyEdges.GetTopologyVertices(i).J;
if (pMesh.Vertices [HalfB.StartVertex].OutgoingHalfedge == -1)
{
pMesh.Vertices [HalfB.StartVertex].OutgoingHalfedge = pMesh.Halfedges.Count + 1;
}
bool[] Match;
int[] ConnectedFaces = source.TopologyEdges.GetConnectedFaces(i, out Match);
//Note for Steve Baer : This Match bool doesn't seem to work on triangulated meshes - it often returns true
//for both faces, even for a properly oriented manifold mesh, which can't be right
//So - making our own check for matching:
//(I suspect the problem is related to C being the same as D for triangles, so best to
//deal with them separately just to make sure)
//loop through the vertices of the face until finding the one which is the same as the start of the edge
//iff the next vertex around the face is the end of the edge then it matches.
Match[0] = false;
if (Match.Length > 1)
{
Match[1] = true;
}
int VertA = source.TopologyVertices.TopologyVertexIndex(source.Faces[ConnectedFaces[0]].A);
int VertB = source.TopologyVertices.TopologyVertexIndex(source.Faces[ConnectedFaces[0]].B);
int VertC = source.TopologyVertices.TopologyVertexIndex(source.Faces[ConnectedFaces[0]].C);
int VertD = source.TopologyVertices.TopologyVertexIndex(source.Faces[ConnectedFaces[0]].D);
if ((VertA == source.TopologyEdges.GetTopologyVertices(i).I) &&
(VertB == source.TopologyEdges.GetTopologyVertices(i).J))
{
Match[0] = true;
}
if ((VertB == source.TopologyEdges.GetTopologyVertices(i).I) &&
(VertC == source.TopologyEdges.GetTopologyVertices(i).J))
{
Match[0] = true;
}
if ((VertC == source.TopologyEdges.GetTopologyVertices(i).I) &&
(VertD == source.TopologyEdges.GetTopologyVertices(i).J))
{
Match[0] = true;
}
if ((VertD == source.TopologyEdges.GetTopologyVertices(i).I) &&
(VertA == source.TopologyEdges.GetTopologyVertices(i).J))
{
Match[0] = true;
}
//I don't think these next 2 should ever be needed, but just in case:
if ((VertC == source.TopologyEdges.GetTopologyVertices(i).I) &&
(VertA == source.TopologyEdges.GetTopologyVertices(i).J))
{
Match[0] = true;
}
if ((VertB == source.TopologyEdges.GetTopologyVertices(i).I) &&
(VertD == source.TopologyEdges.GetTopologyVertices(i).J))
{
Match[0] = true;
}
if (Match[0] == true)
{
HalfA.AdjacentFace = ConnectedFaces[0];
if (pMesh.Faces[HalfA.AdjacentFace].FirstHalfedge == -1)
{
pMesh.Faces[HalfA.AdjacentFace].FirstHalfedge = pMesh.Halfedges.Count;
}
if (ConnectedFaces.Length > 1)
{
HalfB.AdjacentFace = ConnectedFaces[1];
if (pMesh.Faces[HalfB.AdjacentFace].FirstHalfedge == -1)
{
pMesh.Faces[HalfB.AdjacentFace].FirstHalfedge = pMesh.Halfedges.Count + 1;
}
}
else
{
HalfB.AdjacentFace = -1;
}
}
else
{
HalfB.AdjacentFace = ConnectedFaces[0];
if (pMesh.Faces[HalfB.AdjacentFace].FirstHalfedge == -1)
{
pMesh.Faces[HalfB.AdjacentFace].FirstHalfedge = pMesh.Halfedges.Count + 1;
}
if (ConnectedFaces.Length > 1)
{
HalfA.AdjacentFace = ConnectedFaces[1];
if (pMesh.Faces[HalfA.AdjacentFace].FirstHalfedge == -1)
{
pMesh.Faces[HalfA.AdjacentFace].FirstHalfedge = pMesh.Halfedges.Count;
}
}
else
{
HalfA.AdjacentFace = -1;
}
}
pMesh.Halfedges.Add(HalfA);
//pMesh.Halfedges[2 * i].Index = 2 * i; //
pMesh.Halfedges.Add(HalfB);
//pMesh.Halfedges[2 * i + 1].Index = 2 * i + 1; //
}
for (int i = 0; i < (pMesh.Halfedges.Count); i += 2)
{
int[] EndNeighbours = source.TopologyVertices.ConnectedTopologyVertices(pMesh.Halfedges[i + 1].StartVertex, true);
for (int j = 0; j < EndNeighbours.Length; j++)
{
if (EndNeighbours[j] == pMesh.Halfedges[i].StartVertex)
{
int EndOfNextHalfedge = EndNeighbours[(j - 1 + EndNeighbours.Length) % EndNeighbours.Length];
int StartOfPrevOfPairHalfedge = EndNeighbours[(j + 1) % EndNeighbours.Length];
int NextEdge = source.TopologyEdges.GetEdgeIndex(pMesh.Halfedges[i + 1].StartVertex, EndOfNextHalfedge);
int PrevPairEdge = source.TopologyEdges.GetEdgeIndex(pMesh.Halfedges[i + 1].StartVertex, StartOfPrevOfPairHalfedge);
if (source.TopologyEdges.GetTopologyVertices(NextEdge).I == pMesh.Halfedges[i + 1].StartVertex)
{
pMesh.Halfedges[i].NextHalfedge = NextEdge * 2;
}
else
{
pMesh.Halfedges[i].NextHalfedge = NextEdge * 2 + 1;
}
if (source.TopologyEdges.GetTopologyVertices(PrevPairEdge).J == pMesh.Halfedges[i + 1].StartVertex)
{
pMesh.Halfedges[i + 1].PrevHalfedge = PrevPairEdge * 2;
}
else
{
pMesh.Halfedges[i + 1].PrevHalfedge = PrevPairEdge * 2 + 1;
}
break;
}
}
int[] StartNeighbours = source.TopologyVertices.ConnectedTopologyVertices(pMesh.Halfedges[i].StartVertex, true);
for (int j = 0; j < StartNeighbours.Length; j++)
{
if (StartNeighbours[j] == pMesh.Halfedges[i + 1].StartVertex)
{
int EndOfNextOfPairHalfedge = StartNeighbours[(j - 1 + StartNeighbours.Length) % StartNeighbours.Length];
int StartOfPrevHalfedge = StartNeighbours[(j + 1) % StartNeighbours.Length];
int NextPairEdge = source.TopologyEdges.GetEdgeIndex(pMesh.Halfedges[i].StartVertex, EndOfNextOfPairHalfedge);
int PrevEdge = source.TopologyEdges.GetEdgeIndex(pMesh.Halfedges[i].StartVertex, StartOfPrevHalfedge);
if (source.TopologyEdges.GetTopologyVertices(NextPairEdge).I == pMesh.Halfedges[i].StartVertex)
{
pMesh.Halfedges[i + 1].NextHalfedge = NextPairEdge * 2;
}
else
{
pMesh.Halfedges[i + 1].NextHalfedge = NextPairEdge * 2 + 1;
}
if (source.TopologyEdges.GetTopologyVertices(PrevEdge).J == pMesh.Halfedges[i].StartVertex)
{
pMesh.Halfedges[i].PrevHalfedge = PrevEdge * 2;
}
else
{
pMesh.Halfedges[i].PrevHalfedge = PrevEdge * 2 + 1;
}
break;
}
}
}
return(pMesh);
}
