public LegacyHull(LegacyHull reference)
    {
        int vertexCount = reference.vertices.Count * 2;

        vertices = new List <Vector3>(vertexCount);
        normals  = new List <Vector3>(vertexCount);
        tangents = new List <Vector4>(vertexCount);
        uvs      = new List <Vector2>(vertexCount);

        vertexToPointMap = new List <Point>(vertexCount);

        points    = new List <Point>(reference.points.Count * 2);
        edges     = new List <Edge>(reference.edges.Count * 2);
        triangles = new List <Triangle>(reference.triangles.Count * 2);
    }
    public void Split(Vector3 localPointOnPlane, Vector3 localPlaneNormal, bool fillCut, UvMapper uvMapper, out IHull resultA, out IHull resultB)
    {
        lock (key)
        {
            if (localPlaneNormal == Vector3.zero)
            {
                localPlaneNormal = Vector3.up;
            }

            LegacyHull a = new LegacyHull(this);
            LegacyHull b = new LegacyHull(this);

            SetIndices();

            bool[] pointAbovePlane;

            AssignPoints(a, b, localPointOnPlane, localPlaneNormal, out pointAbovePlane);

            int[] oldToNewVertex;

            AssignVertices(a, b, pointAbovePlane, out oldToNewVertex);

            bool[]    edgeIntersectsPlane;
            EdgeHit[] edgeHits;

            AssignEdges(a, b, pointAbovePlane, localPointOnPlane, localPlaneNormal, out edgeIntersectsPlane, out edgeHits);

            IList <Edge> cutEdgesA, cutEdgesB;

            AssignTriangles(a, b, pointAbovePlane, edgeIntersectsPlane, edgeHits, oldToNewVertex, out cutEdgesA, out cutEdgesB);

            if (fillCut)
            {
                SortCutEdges(cutEdgesA, cutEdgesB);

                FillCutEdges(a, b, cutEdgesA, cutEdgesB, localPlaneNormal, uvMapper);
            }

            ValidateOutput(a, b, localPlaneNormal);

            Clear();

            // Set output
            resultA = a;
            resultB = b;
        }
    }
    private void AssignVertices(LegacyHull a, LegacyHull b, bool[] pointAbovePlane, out int[] oldToNewVertex)
    {
        oldToNewVertex = new int[vertices.Count];

        for (int i = 0; i < vertices.Count; i++)
        {
            Point correspondingPoint = vertexToPointMap[i];

            if (pointAbovePlane[correspondingPoint.index])
            {
                // Assign this vertex to hull A
                a.AddVertex(vertices[i], normals[i], tangents[i], uvs[i], correspondingPoint, out oldToNewVertex[i]);
            }
            else
            {
                // Assign this vertex to hull B
                b.AddVertex(vertices[i], normals[i], tangents[i], uvs[i], correspondingPoint, out oldToNewVertex[i]);
            }
        }
    }
    private void ValidateOutput(LegacyHull a, LegacyHull b, Vector3 planeNormal)
    {
        float lengthA = a.LengthAlongAxis(planeNormal);
        float lengthB = b.LengthAlongAxis(planeNormal);

        float sum = lengthA + lengthB;

        if (sum < smallestValidLength)
        {
            a.Clear();
            b.Clear();
        }
        else if (lengthA / sum < smallestValidRatio)
        {
            a.Clear();
        }
        else if (lengthB / sum < smallestValidRatio)
        {
            b.Clear();
        }
    }
    private void AssignPoints(LegacyHull a, LegacyHull b, Vector3 pointOnPlane, Vector3 planeNormal, out bool[] pointAbovePlane)
    {
        pointAbovePlane = new bool[points.Count];

        foreach (Point point in points)
        {
            bool abovePlane = Vector3.Dot(point.position - pointOnPlane, planeNormal) >= 0.0f;

            pointAbovePlane[point.index] = abovePlane;

            if (abovePlane)
            {
                // Assign this point to hull A
                a.points.Add(point);
            }
            else
            {
                // Assign this point to hull B
                b.points.Add(point);
            }
        }
    }
    private void FillCutEdges(LegacyHull a, LegacyHull b, IList <Edge> edgesA, IList <Edge> edgesB, Vector3 planeNormal, UvMapper uvMapper)
    {
        // Create outline data
        int outlineEdgeCount = edgesA.Count;

        Vector3[] outlinePoints = new Vector3[outlineEdgeCount];
        int[]     outlineEdges  = new int[outlineEdgeCount * 2];

        int startIndex = 0;

        for (int i = 0; i < outlineEdgeCount; i++)
        {
            int currentIndex = i;
            int nextIndex    = (i + 1) % outlineEdgeCount;

            Edge current = edgesA[currentIndex];
            Edge next    = edgesA[nextIndex];

            // Set point
            outlinePoints[i] = current.point0.position;

            // Set edge
            outlineEdges[i * 2 + 0] = currentIndex;

            if (current.point1 == next.point0)
            {
                outlineEdges[i * 2 + 1] = nextIndex;
            }
            else
            {
                outlineEdges[i * 2 + 1] = startIndex;

                startIndex = nextIndex;
            }
        }

        // Triangulate
        int[] newEdges, newTriangles, newTriangleEdges;

        ITriangulator triangulator = new Triangulator(outlinePoints, outlineEdges, planeNormal);

        triangulator.Fill(out newEdges, out newTriangles, out newTriangleEdges);

        // Calculate vertex properties
        Vector3 normalA = -planeNormal;
        Vector3 normalB = planeNormal;

        Vector4[] tangentsA, tangentsB;
        Vector2[] uvsA, uvsB;

        uvMapper.Map(outlinePoints, planeNormal, out tangentsA, out tangentsB, out uvsA, out uvsB);

        // Create new vertices
        int[] verticesA = new int[outlineEdgeCount];
        int[] verticesB = new int[outlineEdgeCount];

        for (int i = 0; i < outlineEdgeCount; i++)
        {
            a.AddVertex(outlinePoints[i], normalA, tangentsA[i], uvsA[i], edgesA[i].point0, out verticesA[i]);

            b.AddVertex(outlinePoints[i], normalB, tangentsB[i], uvsB[i], edgesB[i].point0, out verticesB[i]);
        }

        // Create new edges
        for (int i = 0; i < newEdges.Length / 2; i++)
        {
            int point0 = newEdges[i * 2 + 0];
            int point1 = newEdges[i * 2 + 1];

            Edge edgeA = new Edge(edgesA[point0].point0, edgesA[point1].point0);
            Edge edgeB = new Edge(edgesB[point0].point0, edgesB[point1].point0);

            edgesA.Add(edgeA);
            edgesB.Add(edgeB);

            a.edges.Add(edgeA);
            b.edges.Add(edgeB);
        }

        // Create new triangles
        for (int i = 0; i < newTriangles.Length / 3; i++)
        {
            int point0 = newTriangles[i * 3 + 0];
            int point1 = newTriangles[i * 3 + 1];
            int point2 = newTriangles[i * 3 + 2];

            int edge0 = newTriangleEdges[i * 3 + 0];
            int edge1 = newTriangleEdges[i * 3 + 1];
            int edge2 = newTriangleEdges[i * 3 + 2];

            Triangle triangleA = new Triangle(verticesA[point0], verticesA[point2], verticesA[point1], edgesA[point0].point0, edgesA[point2].point0, edgesA[point1].point0, edgesA[edge2], edgesA[edge1], edgesA[edge0]);
            Triangle triangleB = new Triangle(verticesB[point0], verticesB[point1], verticesB[point2], edgesB[point0].point0, edgesB[point1].point0, edgesB[point2].point0, edgesB[edge0], edgesB[edge1], edgesB[edge2]);

            a.triangles.Add(triangleA);
            b.triangles.Add(triangleB);
        }
    }
    private void SplitTriangle(LegacyHull topHull, LegacyHull bottomHull, Edge topEdge0, Edge topEdge1, Edge topCutEdge, Edge bottomEdge0, Edge bottomEdge1, Edge bottomCutEdge, Edge bottomEdge2, int vertex0, int vertex1, int vertex2, float scalar0, float scalar1, int[] oldToNewVertex)
    {
        Vector3 n0 = normals[vertex0];
        Vector3 n1 = normals[vertex1];
        Vector3 n2 = normals[vertex2];

        Vector4 t0 = tangents[vertex0];
        Vector4 t1 = tangents[vertex1];
        Vector4 t2 = tangents[vertex2];

        Vector2 uv0 = uvs[vertex0];
        Vector2 uv1 = uvs[vertex1];
        Vector2 uv2 = uvs[vertex2];

        // Calculate the cut vertex data by interpolating original triangle values
        Vector3 cutNormal0 = new Vector3();

        cutNormal0.x = n0.x + (n1.x - n0.x) * scalar0;
        cutNormal0.y = n0.y + (n1.y - n0.y) * scalar0;
        cutNormal0.z = n0.z + (n1.z - n0.z) * scalar0;

        cutNormal0.Normalize();

        Vector3 cutNormal1 = new Vector3();

        cutNormal1.x = n1.x + (n2.x - n1.x) * scalar1;
        cutNormal1.y = n1.y + (n2.y - n1.y) * scalar1;
        cutNormal1.z = n1.z + (n2.z - n1.z) * scalar1;

        cutNormal1.Normalize();

        Vector4 cutTangent0 = new Vector4();

        cutTangent0.x = t0.x + (t1.x - t0.x) * scalar0;
        cutTangent0.y = t0.y + (t1.y - t0.y) * scalar0;
        cutTangent0.z = t0.z + (t1.z - t0.z) * scalar0;

        cutTangent0.Normalize();
        cutTangent0.w = t0.w;

        Vector4 cutTangent1 = new Vector4();

        cutTangent1.x = t1.x + (t2.x - t1.x) * scalar1;
        cutTangent1.y = t1.y + (t2.y - t1.y) * scalar1;
        cutTangent1.z = t1.z + (t2.z - t1.z) * scalar1;

        cutTangent1.Normalize();
        cutTangent1.w = t1.w;

        Vector2 cutUv0 = new Vector2();

        cutUv0.x = uv0.x + (uv1.x - uv0.x) * scalar0;
        cutUv0.y = uv0.y + (uv1.y - uv0.y) * scalar0;

        Vector2 cutUv1 = new Vector2();

        cutUv1.x = uv1.x + (uv2.x - uv1.x) * scalar1;
        cutUv1.y = uv1.y + (uv2.y - uv1.y) * scalar1;

        // Add the cut vertices to the hulls
        int topCutVertex0, topCutVertex1;

        topHull.AddVertex(topEdge0.point0.position, cutNormal0, cutTangent0, cutUv0, topEdge0.point0, out topCutVertex0);

        topHull.AddVertex(topEdge1.point0.position, cutNormal1, cutTangent1, cutUv1, topEdge1.point0, out topCutVertex1);

        int bottomCutVertex0, bottomCutVertex1;

        bottomHull.AddVertex(bottomEdge0.point0.position, cutNormal0, cutTangent0, cutUv0, bottomEdge0.point0, out bottomCutVertex0);

        bottomHull.AddVertex(bottomEdge1.point0.position, cutNormal1, cutTangent1, cutUv1, bottomEdge1.point0, out bottomCutVertex1);

        // Create the top of the original triangle
        Triangle topTriangle = new Triangle(topCutVertex0, oldToNewVertex[vertex1], topCutVertex1, topEdge0.point0, topEdge0.point1, topEdge1.point0, topEdge0, topEdge1, topCutEdge);

        topHull.triangles.Add(topTriangle);

        // Create the bottom of the original triangle
        Edge bottomCrossEdge = new Edge(bottomEdge0.point1, bottomEdge1.point0);

        Triangle bottomTriangle0 = new Triangle(oldToNewVertex[vertex0], bottomCutVertex0, bottomCutVertex1, bottomEdge0.point1, bottomEdge0.point0, bottomEdge1.point0, bottomEdge0, bottomCutEdge, bottomCrossEdge);
        Triangle bottomTriangle1 = new Triangle(oldToNewVertex[vertex0], bottomCutVertex1, oldToNewVertex[vertex2], bottomEdge0.point1, bottomEdge1.point0, bottomEdge1.point1, bottomCrossEdge, bottomEdge1, bottomEdge2);

        bottomHull.edges.Add(bottomCrossEdge);
        bottomHull.triangles.Add(bottomTriangle0);
        bottomHull.triangles.Add(bottomTriangle1);
    }
    private void AssignTriangles(LegacyHull a, LegacyHull b, bool[] pointAbovePlane, bool[] edgeIntersectsPlane, EdgeHit[] edgeHits, int[] oldToNewVertex, out IList <Edge> cutEdgesA, out IList <Edge> cutEdgesB)
    {
        cutEdgesA = new List <Edge>();
        cutEdgesB = new List <Edge>();

        foreach (Triangle triangle in triangles)
        {
            bool abovePlane0 = pointAbovePlane[triangle.point0.index];
            bool abovePlane1 = pointAbovePlane[triangle.point1.index];
            bool abovePlane2 = pointAbovePlane[triangle.point2.index];

            if (abovePlane0 && abovePlane1 && abovePlane2)
            {
                // Assign this triangle to hull A
                triangle.vertex0 = oldToNewVertex[triangle.vertex0];
                triangle.vertex1 = oldToNewVertex[triangle.vertex1];
                triangle.vertex2 = oldToNewVertex[triangle.vertex2];

                a.triangles.Add(triangle);
            }
            else if (!abovePlane0 && !abovePlane1 && !abovePlane2)
            {
                // Assign this triangle to hull B
                triangle.vertex0 = oldToNewVertex[triangle.vertex0];
                triangle.vertex1 = oldToNewVertex[triangle.vertex1];
                triangle.vertex2 = oldToNewVertex[triangle.vertex2];

                b.triangles.Add(triangle);
            }
            else
            {
                // Split triangle
                Point topPoint;
                Edge  edge0, edge1, edge2;
                int   vertex0, vertex1, vertex2;

                if (edgeIntersectsPlane[triangle.edge0.index] && edgeIntersectsPlane[triangle.edge1.index])
                {
                    topPoint = triangle.point1;
                    edge0    = triangle.edge0;
                    edge1    = triangle.edge1;
                    edge2    = triangle.edge2;
                    vertex0  = triangle.vertex0;
                    vertex1  = triangle.vertex1;
                    vertex2  = triangle.vertex2;
                }
                else if (edgeIntersectsPlane[triangle.edge1.index] && edgeIntersectsPlane[triangle.edge2.index])
                {
                    topPoint = triangle.point2;
                    edge0    = triangle.edge1;
                    edge1    = triangle.edge2;
                    edge2    = triangle.edge0;
                    vertex0  = triangle.vertex1;
                    vertex1  = triangle.vertex2;
                    vertex2  = triangle.vertex0;
                }
                else
                {
                    topPoint = triangle.point0;
                    edge0    = triangle.edge2;
                    edge1    = triangle.edge0;
                    edge2    = triangle.edge1;
                    vertex0  = triangle.vertex2;
                    vertex1  = triangle.vertex0;
                    vertex2  = triangle.vertex1;
                }

                EdgeHit edgeHit0 = edgeHits[edge0.index];
                EdgeHit edgeHit1 = edgeHits[edge1.index];

                // Convert edge hit scalars to the triangle winding order
                float scalar0 = topPoint == edge0.point1 ? edgeHit0.scalar : 1.0f - edgeHit0.scalar;
                float scalar1 = topPoint == edge1.point0 ? edgeHit1.scalar : 1.0f - edgeHit1.scalar;

                Edge cutEdgeA, cutEdgeB;

                if (pointAbovePlane[topPoint.index])
                {
                    // Assign top triangle to hull A, bottom triangle to hull B
                    cutEdgeA = new Edge(edgeHit1.splitA.point0, edgeHit0.splitA.point0);
                    cutEdgeB = new Edge(edgeHit1.splitB.point0, edgeHit0.splitB.point0);

                    a.edges.Add(cutEdgeA);
                    b.edges.Add(cutEdgeB);

                    SplitTriangle(a, b, edgeHit0.splitA, edgeHit1.splitA, cutEdgeA, edgeHit0.splitB, edgeHit1.splitB, cutEdgeB, edge2, vertex0, vertex1, vertex2, scalar0, scalar1, oldToNewVertex);
                }
                else
                {
                    // Assign top triangle to hull B, bottom triangle to hull A
                    cutEdgeA = new Edge(edgeHit0.splitA.point0, edgeHit1.splitA.point0);
                    cutEdgeB = new Edge(edgeHit0.splitB.point0, edgeHit1.splitB.point0);

                    a.edges.Add(cutEdgeA);
                    b.edges.Add(cutEdgeB);

                    SplitTriangle(b, a, edgeHit0.splitB, edgeHit1.splitB, cutEdgeB, edgeHit0.splitA, edgeHit1.splitA, cutEdgeA, edge2, vertex0, vertex1, vertex2, scalar0, scalar1, oldToNewVertex);
                }

                cutEdgesA.Add(cutEdgeA);
                cutEdgesB.Add(cutEdgeB);
            }
        }
    }
    private void AssignEdges(LegacyHull a, LegacyHull b, bool[] pointAbovePlane, Vector3 pointOnPlane, Vector3 planeNormal, out bool[] edgeIntersectsPlane, out EdgeHit[] edgeHits)
    {
        edgeIntersectsPlane = new bool[edges.Count];
        edgeHits            = new EdgeHit[edges.Count];

        foreach (Edge edge in edges)
        {
            bool abovePlane0 = pointAbovePlane[edge.point0.index];
            bool abovePlane1 = pointAbovePlane[edge.point1.index];

            if (abovePlane0 && abovePlane1)
            {
                // Assign this edge to hull A
                a.edges.Add(edge);
            }
            else if (!abovePlane0 && !abovePlane1)
            {
                // Assign this edge to hull B
                b.edges.Add(edge);
            }
            else
            {
                // Split edge
                float denominator = Vector3.Dot(edge.line, planeNormal);
                float scalar      = Mathf.Clamp01(Vector3.Dot(pointOnPlane - edge.point0.position, planeNormal) / denominator);

                Vector3 intersection = edge.point0.position + edge.line * scalar;

                // Create new points
                Point pointA = new Point(intersection);
                Point pointB = new Point(intersection);

                a.points.Add(pointA);
                b.points.Add(pointB);

                // Create new edges
                Edge splitA, splitB;

                if (pointAbovePlane[edge.point0.index])
                {
                    splitA = new Edge(pointA, edge.point0);
                    splitB = new Edge(pointB, edge.point1);
                }
                else
                {
                    splitA = new Edge(pointA, edge.point1);
                    splitB = new Edge(pointB, edge.point0);
                }

                a.edges.Add(splitA);
                b.edges.Add(splitB);

                // Set flags
                edgeIntersectsPlane[edge.index] = true;

                edgeHits[edge.index]        = new EdgeHit();
                edgeHits[edge.index].scalar = scalar;
                edgeHits[edge.index].splitA = splitA;
                edgeHits[edge.index].splitB = splitB;
            }
        }
    }