// Every face should be a triangle! So call Triangulate first
public void SplitInLeftAndRightMesh(HalfEdgeMesh left, HalfEdgeMesh right)
{
// Have to re-index everything :(
Dictionary <Vector3, short> leftVertDict = new Dictionary <Vector3, short>();
Dictionary <Vector3, short> rightVertDict = new Dictionary <Vector3, short>();
// First add the vertices, and get their indices
short lVertIdx = 0;
short rVertIdx = 0;
foreach (HEVertex v in vertices)
{
HEVertex newVL = new HEVertex {
v = v.v, heIndex = v.heIndex
};
HEVertex newVR = new HEVertex {
v = v.v, heIndex = v.heIndex
};
if (v.config == PlaneConfig.Left)
{
newVL.config = PlaneConfig.Left;
leftVertDict.Add(v.v, lVertIdx);
left.vertices.Add(newVL);
lVertIdx++;
}
else if (v.config == PlaneConfig.Right)
{
newVR.config = PlaneConfig.Right;
rightVertDict.Add(v.v, rVertIdx);
right.vertices.Add(newVR);
rVertIdx++;
}
else
{
newVR.config = PlaneConfig.On;
newVL.config = PlaneConfig.On;
leftVertDict.Add(v.v, lVertIdx);
left.vertices.Add(newVL);
lVertIdx++;
rightVertDict.Add(v.v, rVertIdx);
right.vertices.Add(newVR);
rVertIdx++;
}
}
// The dicts should map old idx -> new idx...
Dictionary <short, short> leftEdgeIdxMap = new Dictionary <short, short>();
Dictionary <short, short> rightEdgeIdxMap = new Dictionary <short, short>();
Dictionary <short, short> leftFaceIdxMap = new Dictionary <short, short>();
Dictionary <short, short> rightFaceIdxMap = new Dictionary <short, short>();
int lEdgeIdx = 0;
int lFaceIdx = 0;
int rEdgeIdx = 0;
int rFaceIdx = 0;
// Build the idx maps
foreach (HalfEdge h in halfEdges)
{
PlaneConfig pConfig = GetFaceConfig(faces[h.faceIndex]);
if (pConfig == PlaneConfig.Left)
{
leftEdgeIdxMap.Add(h.index, (short)lEdgeIdx);
left.halfEdges.Add(h.Copy());
lEdgeIdx++;
if (!leftFaceIdxMap.ContainsKey(h.faceIndex))
{
left.faces.Add(faces[h.faceIndex].Copy());
left.faces[lFaceIdx].heIndex = (short)(lEdgeIdx - 1);
leftFaceIdxMap.Add(h.faceIndex, (short)lFaceIdx);
lFaceIdx++;
}
}
else if (pConfig == PlaneConfig.Right)
{
rightEdgeIdxMap.Add(h.index, (short)rEdgeIdx);
right.halfEdges.Add(h.Copy());
rEdgeIdx++;
if (!rightFaceIdxMap.ContainsKey(h.faceIndex))
{
right.faces.Add(faces[h.faceIndex].Copy());
right.faces[rFaceIdx].heIndex = (short)(rEdgeIdx - 1);
rightFaceIdxMap.Add(h.faceIndex, (short)rFaceIdx);
rFaceIdx++;
}
}
else // On, not possible for a face?
{
// ...
}
}
// Update all the indices and stuff
// Edge case is if both vertices are ON the plane, then they don't have an opposite edge
// I think I will leave it and deal with it when triangulating the cap
foreach (KeyValuePair <short, short> kvp in leftEdgeIdxMap)
{
// The edge
left.halfEdges[kvp.Value].faceIndex = leftFaceIdxMap[halfEdges[kvp.Key].faceIndex];
left.halfEdges[kvp.Value].nextIndex = leftEdgeIdxMap[halfEdges[kvp.Key].nextIndex];
left.halfEdges[kvp.Value].verIndex = leftVertDict[vertices[halfEdges[kvp.Key].verIndex].v];
left.halfEdges[kvp.Value].index = kvp.Value;
// face done in loop above
// Update vertices edge index, doesn't matter if we overwrite
left.vertices[left.halfEdges[kvp.Value].verIndex].heIndex = kvp.Value;
}
foreach (KeyValuePair <short, short> kvp in rightEdgeIdxMap)
{
// The edge
right.halfEdges[kvp.Value].faceIndex = rightFaceIdxMap[halfEdges[kvp.Key].faceIndex];
right.halfEdges[kvp.Value].nextIndex = rightEdgeIdxMap[halfEdges[kvp.Key].nextIndex];
right.halfEdges[kvp.Value].verIndex = rightVertDict[vertices[halfEdges[kvp.Key].verIndex].v];
right.halfEdges[kvp.Value].index = kvp.Value;
// face done in loop above
// Update vertices edge index, doesn't matter if we overwrite
right.vertices[right.halfEdges[kvp.Value].verIndex].heIndex = kvp.Value;
}
}
public void CutWithPlane(Plane plane)
{
float sTime = Time.realtimeSinceStartup;
GameObject child = gameObject.transform.GetChild(0).gameObject;
meshFilter = child.GetComponent <MeshFilter>();
mesh = meshFilter.mesh;
InitHalfEdgeMesh();
bool[] visited = new bool[heMesh.halfEdges.Count];
List <HalfEdge> newHalfEdges = new List <HalfEdge>();
int s = heMesh.halfEdges.Count;
int rightCount = 0;
int leftCount = 0;
Vector3 newVertCoord = Vector3.zero;
int onCount = 0;
/*
* Dictionary<Vector3, Vector2> uvMap = new Dictionary<Vector3, Vector2>();
* List<Vector2> uvs = new List<Vector2>();
* mesh.GetUVs(0, uvs);
* for (int i = 0; i < mesh.vertices.Length; i++)
* {
* if (!uvMap.ContainsKey(mesh.vertices[i])) {
* uvMap.Add(mesh.vertices[i], uvs[i]);
* }
* }*/
for (int i = 0; i < s; i++)
{
if (visited[i])
{
continue;
}
// mark this and the opposite as visited
HalfEdge he = heMesh.halfEdges[i];
HalfEdge heOpp = heMesh.halfEdges[he.oppositeIndex];
visited[he.index] = true;
visited[heOpp.index] = true;
// Check if intersection with plane
Vector3 v0 = heMesh.vertices[he.verIndex].v;
Vector3 v1 = heMesh.vertices[heOpp.verIndex].v;
// First Set vertex plane config
Vector3 c0 = v0 - plane.point;
Vector3 c1 = v1 - plane.point;
float c0_dot = Vector3.Dot(c0, plane.normal);
float c1_dot = Vector3.Dot(c1, plane.normal);
float eps = 0.0001f;
if (Mathf.Abs(c0_dot) < eps)
{
heMesh.vertices[he.verIndex].config = PlaneConfig.On;
}
else if (c0_dot <= -eps)
{
heMesh.vertices[he.verIndex].config = PlaneConfig.Right;
rightCount++;
}
else if (c0_dot >= eps)
{
heMesh.vertices[he.verIndex].config = PlaneConfig.Left;
leftCount++;
}
if (Mathf.Abs(c1_dot) < eps)
{
heMesh.vertices[heOpp.verIndex].config = PlaneConfig.On;
}
else if (c1_dot <= -eps)
{
rightCount++;
heMesh.vertices[heOpp.verIndex].config = PlaneConfig.Right;
}
else if (c1_dot >= eps)
{
leftCount++;
heMesh.vertices[heOpp.verIndex].config = PlaneConfig.Left;
}
float t;
Vector3 iPoint = Plane.LinePlaneIntersect(plane, v0, v1, out t);
if (t > 1.0f - eps || t < 0.0f + eps)
{
// No intersection on line segment OR parallel with plane
continue;
}
// Debug.Log(t);
// add new intersection vertex to half-edge structure
HEVertex iVert = new HEVertex();
iVert.v = iPoint;
onCount += 1;
newVertCoord += iPoint;
iVert.heIndex = (short)heMesh.halfEdges.Count;
iVert.config = PlaneConfig.On;
heMesh.vertices.Add(iVert);
HalfEdge[] newHEs = HalfEdge.CreateFromTwo(he, heOpp, (short)heMesh.halfEdges.Count, (short)(heMesh.vertices.Count - 1));
heMesh.halfEdges.Add(newHEs[0]);
heMesh.halfEdges.Add(newHEs[1]);
iPoints.Add(iPoint);
}
if (leftCount == 0 || rightCount == 0)
{
// Do nothing!!!!
return;
}
heMesh.Triangulate();
HalfEdgeMesh rightMesh = new HalfEdgeMesh();
HalfEdgeMesh leftMesh = new HalfEdgeMesh();
heMesh.SplitInLeftAndRightMesh(leftMesh, rightMesh);
GameObject copy = Instantiate(objectToCopy);
GameObject childCopy = copy.transform.GetChild(0).gameObject;
SliceableWithPlane copyDebug = copy.GetComponent <SliceableWithPlane>();
newVertCoord /= (float)onCount;
rightMesh.CapClipPlane(plane.normal, newVertCoord);
copyDebug.heMesh = rightMesh;
copyDebug.meshFilter = childCopy.GetComponent <MeshFilter>();
copyDebug.meshFilter.mesh = rightMesh.GetMesh();
// MeshFilter mfCpy = copy.GetComponent<MeshFilter>();
leftMesh.CapClipPlane(-plane.normal, newVertCoord);
meshFilter.mesh = leftMesh.GetMesh();
/*
* List<Vector2> newUVs = new List<Vector2>();
* foreach (Vector3 v in meshFilter.mesh.vertices)
* {
* if (!uvMap.ContainsKey(v))
* {
* newUVs.Add(Vector2.zero);
* } else
* {
* newUVs.Add(uvMap[v]);
* }
* }
* meshFilter.mesh.SetUVs(0, newUVs);
*/
copyDebug.cutPlane = cutPlane;
//heMesh.CreateStructureFromMesh(mesh);
//copyDebug.heMesh.CreateStructureFromMesh(copyDebug.meshFilter.mesh);
child.GetComponent <MeshCollider>().sharedMesh = null;
child.GetComponent <MeshCollider>().sharedMesh = meshFilter.mesh;
childCopy.GetComponent <MeshCollider>().sharedMesh = null;
childCopy.GetComponent <MeshCollider>().sharedMesh = copyDebug.meshFilter.mesh;
// child.GetComponent<MeshCollider>().gameObject.SetActive(true);
float eTime = Time.realtimeSinceStartup - sTime;
Debug.Log("Time taken = " + eTime);
}
public void CreateStructureFromMesh(Mesh mesh)
{
faces.Clear();
vertices.Clear();
halfEdges.Clear();
int[] meshTriangles = mesh.triangles;
Vector3[] meshVertices = mesh.vertices;
Vector3[] meshNormals = mesh.normals;
// One face per triangle. Add normals
for (int i = 0; i < meshTriangles.Length; i += 3)
{
HEFace f = new HEFace();
// Take the mean of the triangle normals
Vector3 n = meshNormals[meshTriangles[i]] + meshNormals[meshTriangles[i + 1]] + meshNormals[meshTriangles[i + 2]];
n = n / 3.0f;
f.normal = n.normalized;
faces.Add(f);
}
// Simplify mesh vertices i.e. remove duplicates.
// There are duplicate vertices since they have different normals
// Use a dictionary to store the vertices and their new indices
Dictionary <Vector3, int> d = new Dictionary <Vector3, int>();
List <Vector3> newVerts = new List <Vector3>();
List <int> newTris = new List <int>();
int newIdx = 0;
for (int i = 0; i < meshVertices.Length; i++)
{
if (!d.ContainsKey(meshVertices[i]))
{
d[meshVertices[i]] = newIdx;
newVerts.Add(meshVertices[i]);
newIdx++;
}
}
// Update the triangle indices to the new vertex indices.
for (int i = 0; i < meshTriangles.Length; i++)
{
newTris.Add(d[meshVertices[meshTriangles[i]]]);
}
// Set to updated values
meshVertices = newVerts.ToArray();
meshTriangles = newTris.ToArray();
// Init the vertices with vertex data, but not half-edge
for (int i = 0; i < meshVertices.Length; i++)
{
HEVertex vert = new HEVertex
{
v = meshVertices[i]
};
vertices.Add(vert);
}
// Dictionary for opposite lookup. Build in first loop over triangles, used in the second.
// key is v0v1
Dictionary <string, List <short> > edgeMap = new Dictionary <string, List <short> >();
// Start with creating the halfedges and filling in everything except oppositite
for (int i = 0; i < meshTriangles.Length; i += 3)
{
// Stored 3-by-3 indices. e.g. 0,1,2 forms the first triangle.
short i0 = (short)i;
short i1 = (short)(i + 1);
short i2 = (short)(i + 2);
// Triangles are in clockwise order in Unity
HalfEdge h0 = new HalfEdge();
HalfEdge h1 = new HalfEdge();
HalfEdge h2 = new HalfEdge();
h0.index = i0;
h1.index = i1;
h2.index = i2;
h0.faceIndex = (short)(i0 / 3);
h1.faceIndex = (short)(i0 / 3);
h2.faceIndex = (short)(i0 / 3);
h0.verIndex = (short)meshTriangles[i];
h1.verIndex = (short)meshTriangles[i + 1];
h2.verIndex = (short)meshTriangles[i + 2];
// Set the vertices halfedge index. It doesn't matter if we overwrite previously set values.
vertices[meshTriangles[i]].heIndex = i0;
vertices[meshTriangles[i + 1]].heIndex = i1;
vertices[meshTriangles[i + 2]].heIndex = i2;
// next entries. Unity wants clockwise order of vertices
h0.nextIndex = h1.index;
h1.nextIndex = h2.index;
h2.nextIndex = h0.index;
// Add them!
halfEdges.Add(h0);
halfEdges.Add(h1);
halfEdges.Add(h2);
// set face HalfEdge index. i0 is a multiple of 3
faces[i0 / 3].heIndex = i0;
// Fill edgemap, three times :)
string sum;
// This check is required so the ordering is consistent
if (h0.verIndex >= h1.verIndex)
{
sum = h0.verIndex.ToString() + h1.verIndex.ToString();
}
else
{
sum = h1.verIndex.ToString() + h0.verIndex.ToString();
}
if (!edgeMap.ContainsKey(sum))
{
List <short> l = new List <short>();
// add the face index
l.Add(i0);
edgeMap.Add(sum, l);
}
else
{
edgeMap[sum].Add(i0);
}
if (h1.verIndex >= h2.verIndex)
{
sum = h1.verIndex.ToString() + h2.verIndex.ToString();
}
else
{
sum = h2.verIndex.ToString() + h1.verIndex.ToString();
}
if (!edgeMap.ContainsKey(sum))
{
List <short> l = new List <short>();
// add the face index
l.Add(i1);
edgeMap.Add(sum, l);
}
else
{
edgeMap[sum].Add(i1);
}
if (h0.verIndex >= h2.verIndex)
{
sum = h0.verIndex.ToString() + h2.verIndex.ToString();
}
else
{
sum = h2.verIndex.ToString() + h0.verIndex.ToString();
}
if (!edgeMap.ContainsKey(sum))
{
List <short> l = new List <short>();
// add the face index
l.Add(i2);
edgeMap.Add(sum, l);
}
else
{
edgeMap[sum].Add(i2);
}
}
// Fill the opposite entries
for (int i = 0; i < meshTriangles.Length; i += 3)
{
// each edge is shared between exactly two faces
// Stored 3-by-3 indices. e.g. 0,1,2 forms the first triangle.
short i0 = (short)i;
short i1 = (short)(i + 1);
short i2 = (short)(i + 2);
HalfEdge h0 = halfEdges[i0];
HalfEdge h1 = halfEdges[i1];
HalfEdge h2 = halfEdges[i2];
// First edge
// Use our edgeMap to find opposites
string sum;
if (h0.verIndex >= h1.verIndex)
{
sum = h0.verIndex.ToString() + h1.verIndex.ToString();
}
else
{
sum = h1.verIndex.ToString() + h0.verIndex.ToString();
}
List <short> l = edgeMap[sum];
short h0Idx = l[0];
short h1Idx = l[1];
halfEdges[h0Idx].oppositeIndex = h1Idx;
halfEdges[h1Idx].oppositeIndex = h0Idx;
// Second edge
if (h1.verIndex >= h2.verIndex)
{
sum = h1.verIndex.ToString() + h2.verIndex.ToString();
}
else
{
sum = h2.verIndex.ToString() + h1.verIndex.ToString();
}
l = edgeMap[sum];
h0Idx = l[0];
h1Idx = l[1];
halfEdges[h0Idx].oppositeIndex = h1Idx;
halfEdges[h1Idx].oppositeIndex = h0Idx;
// Third edge
if (h0.verIndex >= h2.verIndex)
{
sum = h0.verIndex.ToString() + h2.verIndex.ToString();
}
else
{
sum = h2.verIndex.ToString() + h0.verIndex.ToString();
}
l = edgeMap[sum];
h0Idx = l[0];
h1Idx = l[1];
halfEdges[h0Idx].oppositeIndex = h1Idx;
halfEdges[h1Idx].oppositeIndex = h0Idx;
}
}
public void CapClipPlane(Vector3 planeNormal, Vector3 newVertCoord)
{
// VERY IMPORTANT: Changes the half-edge structure but it is not a complete structure!
// No oppositeIndices are added. Can be made complete by generating the mesh and then turn the mesh
// into a half-edge structure. Major hack and major performance loss.
// Idea:
// Cap the clip by generating a new vertex at the center of the clipping area.
// Then take all faces with two ON vertices and create a new face :- )
// Then do MeshFromHalfedge -> and back again for a good half-edge structure....
// Calculate new vertex pos
Vector3 centerVert = new Vector3(0.0f, 0.0f, 0.0f);
foreach (HEVertex v in vertices)
{
if (v.config == PlaneConfig.On)
{
centerVert += v.v;
}
}
centerVert = centerVert / (float)vertices.Count;
HEVertex newVert = new HEVertex
{
v = newVertCoord,
config = PlaneConfig.On
};
vertices.Add(newVert);
short verIdx = (short)(vertices.Count - 1);
// Get all faces with two ON vertices
Dictionary <short, List <short> > onFaces = GetTwoOnFaces();
foreach (KeyValuePair <short, List <short> > kvp in onFaces)
{
// Make new face
HalfEdge h0 = new HalfEdge();
HalfEdge h1 = new HalfEdge();
HalfEdge h2 = new HalfEdge();
short heIdx = (short)(halfEdges.Count);
h0.index = heIdx;
h1.index = (short)(heIdx + 1);
h2.index = (short)(heIdx + 2);
h0.nextIndex = h1.index;
h1.nextIndex = h2.index;
h2.nextIndex = h0.index;
h0.verIndex = kvp.Value[0];
h1.verIndex = verIdx;
h2.verIndex = kvp.Value[1];
// check correct winding order
Vector3 v1 = (vertices[h1.verIndex].v - vertices[h0.verIndex].v).normalized;
Vector3 v2 = (vertices[h2.verIndex].v - vertices[h0.verIndex].v).normalized;
Vector3 c = Vector3.Cross(v1, v2).normalized;
Vector3 diff = c - planeNormal;
float diff_m = diff.magnitude;
// Debug.Log("Cross = " + (Vector3.Cross(v1.normalized, v2.normalized) - planeNormal.normalized).magnitude + ". Normal = " + planeNormal + ". " + (Vector3.Cross(v1.normalized, v2.normalized)));
if (diff_m >= 0.01f)
{
h0.nextIndex = h2.index;
h1.nextIndex = h0.index;
h2.nextIndex = h1.index;
}
HEFace newFace = new HEFace
{
heIndex = h0.index,
normal = planeNormal
};
short faceIdx = (short)faces.Count;
h0.faceIndex = faceIdx;
h1.faceIndex = faceIdx;
h2.faceIndex = faceIdx;
halfEdges.Add(h0);
halfEdges.Add(h1);
halfEdges.Add(h2);
faces.Add(newFace);
}
}
/**
* Splits a vertex in two along a plane. Returns true if the vertex can be split, false otherwise. Does not create new border
* edges inside the tear in order to prevent non-manifold vertices emerging, so it is only suitable for realtime cloth tearing.
* \param vertex the vertex to split.
* \param splitPlane plane to split the vertex at.
* \param newVertex the newly created vertex after the split operation has been performed.
* \param vertices new mesh vertices list after the split operation.
* \param removedEdges list of edge ids removed after splitting the vertex.
* \param addedEdges list of edge ids added after splitting the vertex.
* \param oldAndNewEdges a dictionary relating old and new edge ids.
*/
public bool SplitVertex(HEVertex vertex, Plane splitPlane, out HEVertex newVertex, out Vector3[] vertices, out HashSet<int> removedEdges, out HashSet<int> addedEdges, out Dictionary<int,int> oldAndNewEdges)
{
// initialize return values:
removedEdges = new HashSet<int>();
addedEdges = new HashSet<int>();
oldAndNewEdges = new Dictionary<int,int>();
newVertex = null;
// initialize face lists for each side of the split plane.
List<HEFace> side1Faces = new List<HEFace>();
List<HEFace> side2Faces = new List<HEFace>();
HashSet<int> side2Edges = new HashSet<int>();
// Get a copy of mesh vertices:
vertices = input.vertices;
// classify adjacent faces depending on which side of the cut plane they reside in:
foreach(HEFace face in GetNeighbourFacesEnumerator(vertex)){
int v1 = heEdges[face.edges[0]].startVertex;
int v2 = heEdges[face.edges[1]].startVertex;
int v3 = heEdges[face.edges[2]].startVertex;
//Skip this face if it doesnt contain the splitted vertex.
if (v1 != vertex.index && v2 != vertex.index && v3 != vertex.index) continue;
Vector3 faceCenter = (vertices[heVertices[v1].physicalIDs[0]] +
vertices[heVertices[v2].physicalIDs[0]] +
vertices[heVertices[v3].physicalIDs[0]]) / 3.0f;
if (splitPlane.GetSide(faceCenter)){
side1Faces.Add(face);
}else{
side2Faces.Add(face);
foreach(int e in face.edges)
side2Edges.Add(e);
}
}
// If the vertex cant be split, return false.
if (side1Faces.Count == 0 || side2Faces.Count == 0) return false;
// create new mesh vertex and triangle buffers:
vertices = new Vector3[input.vertexCount+1];
Array.Copy(input.vertices,vertices,input.vertexCount);
int[] triangles = input.triangles;
// create a new vertex:
newVertex = new HEVertex(input.vertexCount);
newVertex.index = heVertices.Count;
heVertices.Add(newVertex);
// add the new vertex to the mesh vertices buffer:
vertices[input.vertexCount] = vertices[vertex.physicalIDs[0]];
// Copy uvs, colors and other mesh info.
Vector2[] uv = null;
Vector2[] uv2 = null;
Vector2[] uv3 = null;
Vector2[] uv4 = null;
Color32[] colors = null;
if (input.uv.Length > 0){
uv = new Vector2[input.uv.Length+1];
Array.Copy(input.uv,uv,input.uv.Length);
uv[input.uv.Length] = uv[vertex.physicalIDs[0]]; //TODO: could cause copying uvs from the other side of the cut...
}
if (input.uv2.Length > 0){
uv2 = new Vector2[input.uv2.Length+1];
Array.Copy(input.uv2,uv2,input.uv2.Length);
uv2[input.uv2.Length] = uv2[vertex.physicalIDs[0]];
}
if (input.uv3.Length > 0){
uv3 = new Vector2[input.uv3.Length+1];
Array.Copy(input.uv3,uv3,input.uv3.Length);
uv3[input.uv3.Length] = uv3[vertex.physicalIDs[0]];
}
if (input.uv4.Length > 0){
uv4 = new Vector2[input.uv4.Length+1];
Array.Copy(input.uv4,uv4,input.uv4.Length);
uv4[input.uv4.Length] = uv4[vertex.physicalIDs[0]];
}
if (input.colors32.Length > 0){
colors = new Color32[input.colors32.Length+1];
Array.Copy(input.colors32,colors,input.colors32.Length);
colors[input.colors32.Length] = colors[vertex.physicalIDs[0]];
}
// rearrange edges at side 1:
foreach(HEFace face in side1Faces){
// find half edges that start or end at the split vertex:
HEEdge edgeIn = heEdges[Array.Find<int>(face.edges,e => heEdges[e].endVertex == vertex.index)];
HEEdge edgeOut = heEdges[Array.Find<int>(face.edges,e => heEdges[e].startVertex == vertex.index)];
int oldInID = ObiUtils.Pair(edgeIn.startVertex,edgeIn.endVertex);
int oldOutID = ObiUtils.Pair(edgeOut.startVertex,edgeOut.endVertex);
if (ShouldRemoveEdge(edgeIn,side2Edges.Contains(edgeIn.pair)))
removedEdges.Add(oldInID);
if (ShouldRemoveEdge(edgeOut,side2Edges.Contains(edgeOut.pair)))
removedEdges.Add(oldOutID);
// stitch half edges to new vertex
edgeIn.endVertex = newVertex.index;
edgeOut.startVertex = newVertex.index;
newVertex.halfEdgeIndex = edgeOut.index;
int newInID = ObiUtils.Pair(edgeIn.startVertex,edgeIn.endVertex);
int newOutID = ObiUtils.Pair(edgeOut.startVertex,edgeOut.endVertex);
addedEdges.Add(newInID);
addedEdges.Add(newOutID);
if (!oldAndNewEdges.ContainsKey(newInID))
oldAndNewEdges.Add(newInID,oldInID);
if (!oldAndNewEdges.ContainsKey(newOutID))
oldAndNewEdges.Add(newOutID,oldOutID);
// update mesh triangle buffer to point at new vertex where needed:
if (triangles[face.index*3] == vertex.physicalIDs[0]) triangles[face.index*3] = newVertex.physicalIDs[0];
if (triangles[face.index*3+1] == vertex.physicalIDs[0]) triangles[face.index*3+1] = newVertex.physicalIDs[0];
if (triangles[face.index*3+2] == vertex.physicalIDs[0]) triangles[face.index*3+2] = newVertex.physicalIDs[0];
}
// update input mesh:
input.vertices = vertices;
input.triangles = triangles;
if (uv != null)
input.uv = uv;
if (uv2 != null)
input.uv2 = uv2;
if (uv3 != null)
input.uv3 = uv3;
if (uv4 != null)
input.uv4 = uv4;
if (colors != null)
input.colors32 = colors;
_closed = false;
_modified = true;
return true;
}
public IEnumerable<HEVertex> GetNeighbourVerticesEnumerator(HEVertex vertex)
{
HEEdge startEdge = heEdges[vertex.halfEdgeIndex];
HEEdge edge = startEdge;
do{
edge = heEdges[edge.pair];
yield return heVertices[edge.startVertex];
edge = heEdges[edge.nextEdgeIndex];
} while (edge != startEdge);
}
public IEnumerable<HEFace> GetNeighbourFacesEnumerator(HEVertex vertex)
{
HEEdge startEdge = heEdges[vertex.halfEdgeIndex];
HEEdge edge = startEdge;
do{
edge = heEdges[edge.pair];
if (edge.faceIndex > -1)
yield return heFaces[edge.faceIndex];
edge = heEdges[edge.nextEdgeIndex];
} while (edge != startEdge);
}
/**
* Analyzes the input mesh and populates the half-edge structure. Can be called as many times you want (for examples if the original mesh is modified).
*/
public IEnumerator Generate()
{
if (input != null){
heFaces.Clear();
heVertices.Clear();
heEdges.Clear();
_area = 0;
_modified = false;
Dictionary<Vector3, HEVertex> vertexBuffer = new Dictionary<Vector3, HEVertex>();
Dictionary<KeyValuePair<int,int>,HEEdge> edgeBuffer = new Dictionary<KeyValuePair<int,int>,HEEdge>();
// Get copies of vertex and triangle buffers:
Vector3[] vertices = input.vertices;
int[] triangles = input.triangles;
// first, create vertices:
for(int i = 0; i < vertices.Length; i++){
//if the vertex already exists, add physical vertex index to it.
HEVertex vertex;
if (vertexBuffer.TryGetValue(vertices[i], out vertex)){
vertex.physicalIDs.Add(i);
}else{
vertex = new HEVertex(i);
}
vertexBuffer[vertices[i]] = vertex;
if (i % 200 == 0)
yield return new CoroutineJob.ProgressInfo("Half-edge: analyzing vertices...",i/(float)vertices.Length);
}
// assign unique indices to vertices:
int index = 0;
foreach(KeyValuePair<Vector3,HEVertex> pair in vertexBuffer){
((HEVertex)pair.Value).index = index;
heVertices.Add(pair.Value);
if (index % 200 == 0)
yield return new CoroutineJob.ProgressInfo("Half-edge: assigning indices...",index/(float)vertices.Length);
index++;
}
// build half edge structure:
for(int i = 0; i<triangles.Length;i+=3){
Vector3 pos1 = vertices[triangles[i]];
Vector3 pos2 = vertices[triangles[i+1]];
Vector3 pos3 = vertices[triangles[i+2]];
HEVertex v1 = vertexBuffer[pos1];
HEVertex v2 = vertexBuffer[pos2];
HEVertex v3 = vertexBuffer[pos3];
// create half edges:
HEEdge e1 = new HEEdge();
e1.index = heEdges.Count;
e1.indexOnFace = 0;
e1.faceIndex = heFaces.Count;
e1.endVertex = v1.index;
e1.startVertex = v2.index;
HEEdge e2 = new HEEdge();
e2.index = heEdges.Count+1;
e2.indexOnFace = 1;
e2.faceIndex = heFaces.Count;
e2.endVertex = v2.index;
e2.startVertex = v3.index;
HEEdge e3 = new HEEdge();
e3.index = heEdges.Count+2;
e3.indexOnFace = 2;
e3.faceIndex = heFaces.Count;
e3.endVertex = v3.index;
e3.startVertex = v1.index;
// link half edges together:
e1.nextEdgeIndex = e3.index;
e2.nextEdgeIndex = e1.index;
e3.nextEdgeIndex = e2.index;
// vertex outgoing half edge indices:
v1.halfEdgeIndex = e3.index;
v2.halfEdgeIndex = e1.index;
v3.halfEdgeIndex = e2.index;
// add edges:
heEdges.Add(e1);
heEdges.Add(e2);
heEdges.Add(e3);
// populate and add face:
HEFace face = new HEFace();
face.edges[0] = e1.index;
face.edges[1] = e2.index;
face.edges[2] = e3.index;
face.area = ObiUtils.TriangleArea(pos1,pos2,pos3);
_area += face.area;
_volume += Vector3.Dot(Vector3.Cross(pos1,pos2),pos3)/6f;
face.index = heFaces.Count;
heFaces.Add(face);
try{
edgeBuffer.Add(new KeyValuePair<int,int>(v1.index,v2.index),e1);
edgeBuffer.Add(new KeyValuePair<int,int>(v2.index,v3.index),e2);
edgeBuffer.Add(new KeyValuePair<int,int>(v3.index,v1.index),e3);
}catch{
Debug.LogError("Your mesh is non manifold, and thus cannot be processed by Obi: more than 1 edge joining the same pair of vertices.");
heFaces.Clear();
heVertices.Clear();
heEdges.Clear();
_area = 0;
yield break;
}
if (i % 500 == 0)
yield return new CoroutineJob.ProgressInfo("Half-edge: generating edges and faces...",i/(float)triangles.Length);
}
List<HEEdge> borderEdges = new List<HEEdge>(); //edges belonging to a mesh border.
// stitch half edge pairs together:
index = 0;
foreach(KeyValuePair<KeyValuePair<int,int>,HEEdge> pair in edgeBuffer){
KeyValuePair<int,int> edgeKey = new KeyValuePair<int,int>(pair.Key.Value,pair.Key.Key);
HEEdge edge = null;
if (edgeBuffer.TryGetValue(edgeKey, out edge)){
((HEEdge)pair.Value).pair = edge.index;
}else{
//create border edge:
HEEdge e = new HEEdge();
e.index = heEdges.Count;
e.endVertex = ((HEEdge)pair.Value).startVertex;
e.startVertex = ((HEEdge)pair.Value).endVertex;
heVertices[e.startVertex].halfEdgeIndex = e.index;
e.pair = ((HEEdge)pair.Value).index;
((HEEdge)pair.Value).pair = e.index;
heEdges.Add(e);
borderEdges.Add(e);
}
if (index % 1000 == 0)
yield return new CoroutineJob.ProgressInfo("Half-edge: stitching half-edges...",index/(float)edgeBuffer.Count);
index++;
}
_closed = borderEdges.Count == 0;
// link together border edges:
foreach(HEEdge edge in borderEdges){
edge.nextEdgeIndex = heVertices[edge.endVertex].halfEdgeIndex;
}
}else{
Debug.LogWarning("Tried to generate adjacency info for an empty mesh.");
}
}
public bool AreLinked(HEVertex v1, HEVertex v2)
{
HEEdge startEdge = heEdges[v1.halfEdgeIndex];
HEEdge edge = startEdge;
do{
edge = heEdges[edge.pair];
if (edge.startVertex == v2.index)
return true;
edge = heEdges[edge.nextEdgeIndex];
} while (edge != startEdge);
return false;
}