Example #1
0
        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();
        }