private static void Join2DGeometries(Geometry first, Geometry second) { var highestVertHandle = first.HighestVertHandle; var highestHalfEdgeHandle = first.HighestHalfEdgeHandle; var highestFaceHandle = first.HighestFaceHandle; var vertDictHelper = new Dictionary <int, Vertex>(); foreach (var v in second.DictVertices) { var vert = new Vertex(v.Value.Handle + highestVertHandle, v.Value.VertData.Pos); vert.IncidentHalfEdge = v.Value.IncidentHalfEdge + highestHalfEdgeHandle; vertDictHelper.Add(vert.Handle, vert); } second.DictVertices.Clear(); second.DictVertices = vertDictHelper; var faceDictHelper = new Dictionary <int, Face>(); foreach (var f in second.DictFaces) { var face = new Face(f.Value.Handle + highestFaceHandle, f.Value); if (face.OuterHalfEdge != default(int)) { var outerHeId = face.OuterHalfEdge + first.HighestHalfEdgeHandle; face.OuterHalfEdge = outerHeId; } for (var k = 0; k < face.InnerHalfEdges.Count; k++) { var innerHe = face.InnerHalfEdges[k]; innerHe = innerHe + first.HighestHalfEdgeHandle; face.InnerHalfEdges[k] = innerHe; } faceDictHelper.Add(face.Handle, face); } second.DictFaces.Clear(); second.DictFaces = faceDictHelper; var heDictHelper = new Dictionary <int, HalfEdge>(); foreach (var he in second.DictHalfEdges) { var halfEdge = new HalfEdge(he.Value.Handle + highestHalfEdgeHandle, he.Value); halfEdge.IncidentFace = halfEdge.IncidentFace + first.HighestFaceHandle; halfEdge.OriginVertex = halfEdge.OriginVertex + first.HighestVertHandle; halfEdge.NextHalfEdge = halfEdge.NextHalfEdge + highestHalfEdgeHandle; halfEdge.PrevHalfEdge = halfEdge.PrevHalfEdge + highestHalfEdgeHandle; if (halfEdge.TwinHalfEdge != default(int)) { halfEdge.TwinHalfEdge = halfEdge.TwinHalfEdge + highestHalfEdgeHandle; } heDictHelper.Add(halfEdge.Handle, halfEdge); } second.DictHalfEdges.Clear(); second.DictHalfEdges = heDictHelper; //Change winding. var hEdgesWChangedWinding = second.GetHalfEdgesWChangedWinding(second.GetAllHalfEdges()).ToList(); //Add data of second geometry to the first. foreach (var vert in second.DictVertices) { first.DictVertices.Add(vert.Key, vert.Value); } foreach (var halfEdge in hEdgesWChangedWinding) { first.DictHalfEdges.Add(halfEdge.Handle, halfEdge); } //Write content of second unbounded face into the first - delete second unbounded face var firstUnbounded = first.DictFaces[first.DictFaces.Keys.Min()]; var secUnbounded = second.DictFaces[second.DictFaces.Keys.Min()]; firstUnbounded.InnerHalfEdges.AddRange(secUnbounded.InnerHalfEdges); second.DictFaces.Remove(secUnbounded.Handle); var secUnboundedHalfEdges = new List <HalfEdge>(); foreach (var he in first.GetAllHalfEdges()) { if (he.IncidentFace == secUnbounded.Handle) { secUnboundedHalfEdges.Add(he); } } //Replace the incident face of the half edges. foreach (var he in secUnboundedHalfEdges) { var halfEdge = he; halfEdge.IncidentFace = firstUnbounded.Handle; first.DictHalfEdges.Remove(halfEdge.Handle); first.DictHalfEdges.Add(halfEdge.Handle, halfEdge); } //Add faces to the first geometry and recalculate the face normals. foreach (var face in second.DictFaces) { first.DictFaces.Add(face.Key, face.Value); first.SetFaceNormal(first.GetFaceOuterVertices(face.Key).ToList(), first.DictFaces[face.Key]); } first.SetHighestHandles(); }