private void StartMeshSimplification()
{
Mesh meshToSimplify = meshInput.sharedMesh;
meshInput.transform.gameObject.SetActive(false);
//
// Change data structure and normalize
//
//Mesh -> MyMesh
MyMesh myMeshToSimplify = new MyMesh(meshToSimplify);
//From local to global space
myMeshToSimplify.vertices = myMeshToSimplify.vertices.Select(x => meshInput.transform.TransformPoint(x.ToVector3()).ToMyVector3()).ToList();
//Normalize to 0-1
//this.normalizer = new Normalizer3(myMeshToSimplify.vertices);
//We only need to normalize the vertices
//myMeshToSimplify.vertices = normalizer.Normalize(myMeshToSimplify.vertices);
HalfEdgeData3 myMeshToSimplify_HalfEdge = new HalfEdgeData3(myMeshToSimplify, HalfEdgeData3.ConnectOppositeEdges.Fast);
//Start
VisualizeMergeEdgesQEM visualizeThisAlgorithm = GetComponent <VisualizeMergeEdgesQEM>();
visualizeThisAlgorithm.StartVisualizer(myMeshToSimplify_HalfEdge, maxEdgesToContract: 2450, maxError: Mathf.Infinity);
}
public void DisplayMeshMain(HalfEdgeData2 meshData, Normalizer2 normalizer)
{
//UnNormalize and to 3d
HalfEdgeData3 meshDataUnNormalized_3d = new HalfEdgeData3();
//We dont want to modify the original data
//HalfEdgeData2 meshDataUnNormalized = normalizer.UnNormalize(meshData);
HashSet <HalfEdgeFace2> faces_2d = meshData.faces;
foreach (HalfEdgeFace2 f in faces_2d)
{
MyVector2 p1 = f.edge.v.position;
MyVector2 p2 = f.edge.nextEdge.v.position;
MyVector2 p3 = f.edge.nextEdge.nextEdge.v.position;
p1 = normalizer.UnNormalize(p1);
p2 = normalizer.UnNormalize(p2);
p3 = normalizer.UnNormalize(p3);
meshDataUnNormalized_3d.AddTriangle(p1.ToMyVector3_Yis3D(), p2.ToMyVector3_Yis3D(), p3.ToMyVector3_Yis3D());
}
this.meshData = meshDataUnNormalized_3d.faces;
DisplayMesh(meshDataUnNormalized_3d.faces, displayMeshHere);
//Normalize again
//meshData = normalizer.Normalize(meshDataUnNormalized);
}
//Display a mesh, which is called from the coroutine when a mesh has changed
public void DisplayMesh(HashSet <HalfEdgeFace3> meshDataUnNormalized, MeshFilter mf)
{
//Generate a mesh
MyMesh myMesh = HalfEdgeData3.ConvertToMyMesh("Main visualization mesh", meshDataUnNormalized, MyMesh.MeshStyle.HardEdges);
Mesh mesh = myMesh.ConvertToUnityMesh(generateNormals: true);
mf.mesh = mesh;
//Debug.Log(mesh.triangles.Length);
}
//These points should be normalized
public void StartVisualizer(HashSet <MyVector3> points)
{
controller = GetComponent <VisualizerController3D>();
HalfEdgeData3 convexHull = new HalfEdgeData3();
//Generate the first tertahedron
IterativeHullAlgorithm3D.BuildFirstTetrahedron(points, convexHull);
//Main visualization algorithm
StartCoroutine(GenerateHull(points, convexHull));
}
private IEnumerator GenerateHull(HashSet <MyVector3> points, HalfEdgeData3 convexHull)
{
//PAUSE FOR VISUALIZATION
//Display what we have so far
controller.DisplayMeshMain(convexHull.faces);
controller.HideAllVisiblePoints(convexHull.verts);
yield return(new WaitForSeconds(10f));
//Add all other points one-by-one
List <MyVector3> pointsToAdd = new List <MyVector3>(points);
foreach (MyVector3 p in pointsToAdd)
{
//Is this point within the tetrahedron
bool isWithinHull = _Intersections.PointWithinConvexHull(p, convexHull);
if (isWithinHull)
{
points.Remove(p);
controller.HideVisiblePoint(p);
continue;
}
//PAUSE FOR VISUALIZATION
//Display active point
controller.DisplayActivePoint(p);
//Rotate camera to this point
//Important to turn this vector to 2d
Vector3 unity_pos = controller.normalizer.UnNormalize(p).ToVector3();
controller.cameraScript.SetWantedHeight(unity_pos.y);
unity_pos.y = 0f;
controller.cameraScript.SetWantedDirection((Vector3.zero - unity_pos).normalized);
yield return(new WaitForSeconds(2f));
//Find visible triangles and edges on the border between the visible and invisible triangles
HashSet <HalfEdgeFace3> visibleTriangles = null;
HashSet <HalfEdge3> borderEdges = null;
IterativeHullAlgorithm3D.FindVisibleTrianglesAndBorderEdgesFromPoint(p, convexHull, out visibleTriangles, out borderEdges);
//Remove all visible triangles
foreach (HalfEdgeFace3 triangle in visibleTriangles)
{
convexHull.DeleteFace(triangle);
}
//PAUSE FOR VISUALIZATION
//For visualization purposes we now need to create two meshes and then remove the triangles again
controller.DisplayMeshMain(convexHull.faces);
controller.DisplayMeshOther(visibleTriangles);
controller.HideAllVisiblePoints(convexHull.verts);
yield return(new WaitForSeconds(2f));
//PAUSE FOR VISUALIZATION
//Remove all now visible triangles that forms the hole
List <HalfEdgeFace3> visibleTrianglesList = new List <HalfEdgeFace3>(visibleTriangles);
for (int i = 0; i < visibleTrianglesList.Count; i++)
{
visibleTriangles.Remove(visibleTrianglesList[i]);
controller.DisplayMeshOther(visibleTriangles);
yield return(new WaitForSeconds(0.5f));
}
//Save all ned edges so we can connect them with an opposite edge
//To make it faster you can use the ideas in the Valve paper to get a sorted list of newEdges
HashSet <HalfEdge3> newEdges = new HashSet <HalfEdge3>();
foreach (HalfEdge3 borderEdge in borderEdges)
{
//Each edge is point TO a vertex
MyVector3 p1 = borderEdge.prevEdge.v.position;
MyVector3 p2 = borderEdge.v.position;
//The border edge belongs to a triangle which is invisible
//Because triangles are oriented clockwise, we have to add the vertices in the other direction
//to build a new triangle with the point
HalfEdgeFace3 newTriangle = convexHull.AddTriangle(p2, p1, p);
//PAUSE FOR VISUALIZATION
controller.DisplayMeshMain(convexHull.faces);
yield return(new WaitForSeconds(0.5f));
//Connect the new triangle with the opposite edge on the border
//When we create the face we give it a reference edge which goes to p2
//So the edge we want to connect is the next edge
HalfEdge3 edgeToConnect = newTriangle.edge.nextEdge;
edgeToConnect.oppositeEdge = borderEdge;
borderEdge.oppositeEdge = edgeToConnect;
//Two edges are still not connected, so save those
HalfEdge3 e1 = newTriangle.edge;
//HalfEdge3 e2 = newTriangle.edge.nextEdge;
HalfEdge3 e3 = newTriangle.edge.nextEdge.nextEdge;
newEdges.Add(e1);
//newEdges.Add(e2);
newEdges.Add(e3);
}
//Two edges in each triangle are still not connected with an opposite edge
foreach (HalfEdge3 e in newEdges)
{
if (e.oppositeEdge != null)
{
continue;
}
convexHull.TryFindOppositeEdge(e, newEdges);
}
//PAUSE FOR VISUALIZATION
//controller.DisplayMeshMain(convexHull.faces);
//yield return new WaitForSeconds(2f);
controller.HideVisiblePoint(p);
}
controller.HideActivePoint();
controller.cameraScript.SetWantedDirection(Vector3.zero);
controller.cameraScript.SetWantedHeight(0f);
//controller.DisplayMeshMain(convexHull.faces);
//yield return new WaitForSeconds(5f);
yield return(null);
}
void Start()
{
vertices_Unity = new HashSet <UnityEngine.Vector3>();
for (int i = 0; i < pointCount; i++)
{
UnityEngine.Vector3 point = srcMesh.mesh.GetRandomPointInsideNonConvex(srcMesh.GetComponent <Renderer>().bounds.center);
vertices_Unity.Add(point);
}
HashSet <Vector3> points = new HashSet <Vector3>(vertices_Unity.Select(x => x.ToMyVector3()));
Normalizer3 normalizer = new Normalizer3(new List <Vector3>(points));
HashSet <Vector3> points_normalized = normalizer.Normalize(points);
//Convex Hull
HalfEdgeData3 convexHull_normalized = _ConvexHull.Iterative_3D(points_normalized, removeUnwantedTriangles: false, normalizer);
//HalfEdgeData3 convexHull_unnormalized = _ConvexHull.Iterative_3D(points, removeUnwantedTriangles: false, normalizer);
var tmp = convexHull_normalized.ConvertToMyMesh("Triangulated Points", MyMesh.MeshStyle.HardEdges);
delaunayMesh = tmp.ConvertToUnityMesh(true);
// if (convexHull_normalized == null)
// {
// Debug.LogError("ConvexHull is null");
// return;
// }
//
HashSet <VoronoiCell3> voronoiCells_normalized = _Voronoi.Delaunay3DToVoronoi(convexHull_normalized);
HalfEdgeData3 convexHull = normalizer.UnNormalize(convexHull_normalized);
MyMesh myMesh = convexHull.ConvertToMyMesh("convex hull aka delaunay triangulation", MyMesh.MeshStyle.HardEdges);
delaunayMesh = myMesh.ConvertToUnityMesh(generateNormals: false);
//Voronoi
HashSet <VoronoiCell3> voronoiCells = normalizer.UnNormalize(voronoiCells_normalized);
//Generate a mesh for each separate cell
voronoiCellsMeshes = GenerateVoronoiCellsMeshes(voronoiCells);
foreach (var mesh in voronoiCellsMeshes)
{
GameObject go = new GameObject();
var meshfilter = go.AddComponent <MeshFilter>();
var renderer = go.AddComponent <MeshRenderer>();
renderer.sharedMaterial = material;
meshfilter.mesh = mesh;
go.transform.parent = gameObject.transform;
}
//Generate a single mesh for all cells where each vertex has a color belonging to that cell
//Now we can display the mesh with an unlit shader where each vertex is associated with a color belonging to that cell
//The problem is that the voronoi cell is not a flat surface on the mesh
//But it looks flat if we are using an unlit shader
// Mesh oneMesh = GenerateAndDisplaySingleMesh(voronoiCellsMeshes);
//
// if (meshFilter != null)
// {
// meshFilter.mesh = oneMesh;
// }
// else
// {
// Debug.LogError("Meshfilter is null");
// }
}
//
// Add the constraints to the delaunay triangulation
//
//timer is for debugging
private IEnumerator AddConstraints(HalfEdgeData2 triangleData, List <MyVector2> constraints, bool shouldRemoveTriangles, Normalizer2 normalizer, System.Diagnostics.Stopwatch timer = null)
{
//Validate the data
if (constraints == null)
{
yield return(null);
}
//
// PAUSE AND VISUALIZE
//
//Show the constraint with a line mesh
HashSet <Triangle2> lineTriangles = _GenerateMesh.ConnectedLineSegments(constraints, width: 0.01f, isConnected: true);
//UnNormalized and to half-edge 3 (also move each vertex up a little or will intersect with the underlying mesh)
HalfEdgeData3 lineData = new HalfEdgeData3();
foreach (Triangle2 t in lineTriangles)
{
MyVector2 p1 = t.p1;
MyVector2 p2 = t.p2;
MyVector2 p3 = t.p3;
p1 = normalizer.UnNormalize(p1);
p2 = normalizer.UnNormalize(p2);
p3 = normalizer.UnNormalize(p3);
lineData.AddTriangle(p1.ToMyVector3_Yis3D(0.1f), p2.ToMyVector3_Yis3D(0.1f), p3.ToMyVector3_Yis3D(0.1f));
}
visualizeController.DisplayMeshOtherUnNormalized(lineData.faces);
yield return(new WaitForSeconds(2f));
//Get a list with all edges
//This is faster than first searching for unique edges
//The report suggest we should do a triangle walk, but it will not work if the mesh has holes
//The mesh has holes because we remove triangles while adding constraints one-by-one
//so maybe better to remove triangles after we added all constraints...
HashSet <HalfEdge2> edges = triangleData.edges;
//The steps numbering is from the report
//Step 1. Loop over each constrained edge. For each of these edges, do steps 2-4
for (int i = 0; i < constraints.Count; i++)
{
//Let each constrained edge be defined by the vertices:
MyVector2 c_p1 = constraints[i];
MyVector2 c_p2 = constraints[MathUtility.ClampListIndex(i + 1, constraints.Count)];
//Check if this constraint already exists in the triangulation,
//if so we are happy and dont need to worry about this edge
//timer.Start();
if (IsEdgeInListOfEdges(edges, c_p1, c_p2))
{
continue;
}
//timer.Stop();
//Step 2. Find all edges in the current triangulation that intersects with this constraint
//Is returning unique edges only, so not one edge going in the opposite direction
//timer.Start();
Queue <HalfEdge2> intersectingEdges = FindIntersectingEdges_BruteForce(edges, c_p1, c_p2);
//timer.Stop();
//Debug.Log("Intersecting edges: " + intersectingEdges.Count);
//Step 3. Remove intersecting edges by flipping triangles
//This takes 0 seconds so is not bottleneck
//timer.Start();
List <HalfEdge2> newEdges = new List <HalfEdge2>();
yield return(StartCoroutine(RemoveIntersectingEdges(c_p1, c_p2, intersectingEdges, newEdges, triangleData, normalizer)));
//timer.Stop();
//Step 4. Try to restore delaunay triangulation
//Because we have constraints we will never get a delaunay triangulation
//This takes 0 seconds so is not bottleneck
//timer.Start();
yield return(StartCoroutine(RestoreDelaunayTriangulation(c_p1, c_p2, newEdges, triangleData, normalizer)));
//timer.Stop();
}
//Step 5. Remove superfluous triangles, such as the triangles "inside" the constraints
if (shouldRemoveTriangles)
{
//timer.Start();
yield return(StartCoroutine(RemoveSuperfluousTriangles(triangleData, constraints, normalizer)));
//timer.Stop();
}
//return triangleData;
//
// PAUSE AND VISUALIZE
//
visualizeController.HideMeshOther();
yield return(new WaitForSeconds(2f));
}
//Generates points, delaunay triangulation, and voronoi diagram
public void Generate()
{
if (radius <= 0f)
{
radius = 0.01f;
}
if (numberOfPoints < 4)
{
numberOfPoints = 4;
}
//Get random points in 3d space
points_Unity = TestAlgorithmsHelpMethods.GenerateRandomPointsOnSphere(seed, radius, numberOfPoints);
//To MyVector3
HashSet <MyVector3> points = new HashSet <MyVector3>(points_Unity.Select(x => x.ToMyVector3()));
//Normalize
Normalizer3 normalizer = new Normalizer3(new List <MyVector3>(points));
HashSet <MyVector3> points_normalized = normalizer.Normalize(points);
System.Diagnostics.Stopwatch timer = new System.Diagnostics.Stopwatch();
//
// Generate the convex hull, which is the same as the Delaunay triangulation of points on the sphere
//
//Iterative algorithm
timer.Start();
HalfEdgeData3 convexHull_normalized = _ConvexHull.Iterative_3D(points_normalized, removeUnwantedTriangles: false, normalizer);
timer.Stop();
Debug.Log($"Generated a 3d convex hull in {timer.ElapsedMilliseconds / 1000f} seconds");
if (convexHull_normalized == null)
{
return;
}
//
// Generate the voronoi diagram from the delaunay triangulation
//
timer.Restart();
HashSet <VoronoiCell3> voronoiCells_normalized = _Voronoi.Delaunay3DToVoronoi(convexHull_normalized);
timer.Stop();
Debug.Log($"Generated a 3d voronoi diagram in {timer.ElapsedMilliseconds / 1000f} seconds");
if (voronoiCells_normalized == null)
{
return;
}
//
// Display
//
//Delaunay
HalfEdgeData3 convexHull = normalizer.UnNormalize(convexHull_normalized);
MyMesh myMesh = convexHull.ConvertToMyMesh("convex hull aka delaunay triangulation", MyMesh.MeshStyle.HardEdges);
delaunayMesh = myMesh.ConvertToUnityMesh(generateNormals: false);
//Voronoi
HashSet <VoronoiCell3> voronoiCells = normalizer.UnNormalize(voronoiCells_normalized);
//Generate a mesh for each separate cell
voronoiCellsMeshes = GenerateVoronoiCellsMeshes(voronoiCells);
//Generate a single mesh for all cells where each vertex has a color belonging to that cell
//Now we can display the mesh with an unlit shader where each vertex is associated with a color belonging to that cell
//The problem is that the voronoi cell is not a flat surface on the mesh
//But it looks flat if we are using an unlit shader
Mesh oneMesh = GenerateAndDisplaySingleMesh(voronoiCellsMeshes);
if (meshFilter != null)
{
meshFilter.mesh = oneMesh;
}
}
public void SimplifyMesh()
{
//Has to be sharedMesh if we are using Editor tools
Mesh meshToSimplify = meshFilterToSimplify.sharedMesh;
//
// Change data structure and normalize
//
//Mesh -> MyMesh
MyMesh myMeshToSimplify = new MyMesh(meshToSimplify);
//Normalize to 0-1
Normalizer3 normalizer = new Normalizer3(myMeshToSimplify.vertices);
//We only need to normalize the vertices
myMeshToSimplify.vertices = normalizer.Normalize(myMeshToSimplify.vertices);
HalfEdgeData3 myMeshToSimplify_HalfEdge = new HalfEdgeData3(myMeshToSimplify, HalfEdgeData3.ConnectOppositeEdges.Fast);
//
// Simplify
//
System.Diagnostics.Stopwatch timer = new System.Diagnostics.Stopwatch();
timer.Start();
HalfEdgeData3 mySimplifiedMesh_HalfEdge = MeshSimplification_QEM.Simplify(myMeshToSimplify_HalfEdge, maxEdgesToContract: 2400, maxError: Mathf.Infinity, normalizeTriangles: true);
timer.Stop();
Debug.Log($"It took {timer.ElapsedMilliseconds / 1000f} seconds to simplify the mesh");
//
// Change data structure and un-normalize
//
timer.Reset();
timer.Start();
//From half-edge to mesh
MyMesh mySimplifiedMesh = mySimplifiedMesh_HalfEdge.ConvertToMyMesh("Simplified mesh", MyMesh.MeshStyle.HardEdges);
//Un-Normalize
mySimplifiedMesh.vertices = normalizer.UnNormalize(mySimplifiedMesh.vertices);
//Convert to global space
Transform trans = meshFilterToSimplify.transform;
mySimplifiedMesh.vertices = mySimplifiedMesh.vertices.Select(x => trans.TransformPoint(x.ToVector3()).ToMyVector3()).ToList();
//Convert to mesh
Mesh unitySimplifiedMesh = mySimplifiedMesh.ConvertToUnityMesh(generateNormals: true, meshName: "simplified mesh");
//Attach to new game object
meshFilterToShowSimplifiedMesh.mesh = unitySimplifiedMesh;
timer.Stop();
Debug.Log($"It took {timer.ElapsedMilliseconds / 1000f} seconds to finalize the mesh after simplifying");
}
public void StartVisualizer(HalfEdgeData3 halfEdgeMeshData, int maxEdgesToContract, float maxError, bool normalizeTriangles = false)
{
controller = GetComponent <VisualizerController3D>();
//
// Compute the Q matrices for all the initial vertices
//
//Put the result in a lookup dictionary
//This assumes we have no floating point precision issues, so vertices at the same position have to be at the same position
Dictionary <MyVector3, Matrix4x4> qMatrices = new Dictionary <MyVector3, Matrix4x4>();
HashSet <HalfEdgeVertex3> vertices = halfEdgeMeshData.verts;
//timer.Start();
//0.142 seconds for the bunny (0.012 for dictionary lookup, 0.024 to calculate the Q matrices, 0.087 to find edges going to vertex)
foreach (HalfEdgeVertex3 v in vertices)
{
//Have we already calculated a Q matrix for this vertex?
//Remember that we have multiple vertices at the same position in the half-edge data structure
//timer.Start();
if (qMatrices.ContainsKey(v.position))
{
continue;
}
//timer.Stop();
//Calculate the Q matrix for this vertex
//timer.Start();
//Find all edges meeting at this vertex
HashSet <HalfEdge3> edgesPointingToThisVertex = v.GetEdgesPointingToVertex(halfEdgeMeshData);
//timer.Stop();
//timer.Start();
Matrix4x4 Q = MeshSimplification_QEM.CalculateQMatrix(edgesPointingToThisVertex, normalizeTriangles);
//timer.Stop();
qMatrices.Add(v.position, Q);
}
//timer.Stop();
//
// Select all valid pairs that can be contracted
//
List <HalfEdge3> validPairs = new List <HalfEdge3>(halfEdgeMeshData.edges);
//
// Compute the cost of contraction for each pair
//
HashSet <QEM_Edge> QEM_edges = new HashSet <QEM_Edge>();
//We need a lookup table to faster remove and update QEM_edges
Dictionary <HalfEdge3, QEM_Edge> halfEdge_QEM_Lookup = new Dictionary <HalfEdge3, QEM_Edge>();
foreach (HalfEdge3 halfEdge in validPairs)
{
MyVector3 p1 = halfEdge.prevEdge.v.position;
MyVector3 p2 = halfEdge.v.position;
Matrix4x4 Q1 = qMatrices[p1];
Matrix4x4 Q2 = qMatrices[p2];
QEM_Edge QEM_edge = new QEM_Edge(halfEdge, Q1, Q2);
QEM_edges.Add(QEM_edge);
halfEdge_QEM_Lookup.Add(halfEdge, QEM_edge);
}
//
// Sort all pairs, with the minimum cost pair at the top
//
//The fastest way to keep the data sorted is to use a heap
Heap <QEM_Edge> sorted_QEM_edges = new Heap <QEM_Edge>(QEM_edges.Count);
foreach (QEM_Edge e in QEM_edges)
{
sorted_QEM_edges.Add(e);
}
//Main visualization algorithm coroutine
StartCoroutine(QEMLoop(halfEdgeMeshData, sorted_QEM_edges, qMatrices, halfEdge_QEM_Lookup, maxEdgesToContract, maxError, normalizeTriangles));
}
private IEnumerator QEMLoop(HalfEdgeData3 halfEdgeMeshData, Heap <QEM_Edge> sorted_QEM_edges, Dictionary <MyVector3, Matrix4x4> qMatrices, Dictionary <HalfEdge3, QEM_Edge> halfEdge_QEM_Lookup, int maxEdgesToContract, float maxError, bool normalizeTriangles = false)
{
//PAUSE FOR VISUALIZATION
//Display what we have so far
controller.DisplayMeshMain(halfEdgeMeshData.faces);
controller.displayStuffUI.text = "Triangles: " + halfEdgeMeshData.faces.Count.ToString();
yield return(new WaitForSeconds(5f));
//
// Start contracting edges
//
//For each edge we want to remove
for (int i = 0; i < maxEdgesToContract; i++)
{
//Check that we can simplify the mesh
//The smallest mesh we can have is a tetrahedron with 4 faces, itherwise we get a flat triangle
if (halfEdgeMeshData.faces.Count <= 4)
{
Debug.Log($"Cant contract more than {i} edges");
break;
}
//
// Remove the pair (v1,v2) of the least cost and contract the pair
//
//timer.Start();
QEM_Edge smallestErrorEdge = sorted_QEM_edges.RemoveFirst();
//This means an edge in this face has already been contracted
//We are never removing edges from the heap after contracting and edges,
//so we do it this way for now, which is maybe better?
if (smallestErrorEdge.halfEdge.face == null)
{
//This edge wasn't contracted so don't add it to iteration
i -= 1;
continue;
}
if (smallestErrorEdge.qem > maxError)
{
Debug.Log($"Cant contract more than {i} edges because reached max error");
break;
}
//timer.Stop();
//timer.Start();
//Get the half-edge we want to contract
HalfEdge3 edgeToContract = smallestErrorEdge.halfEdge;
//Need to save the endpoints so we can remove the old Q matrices from the pos-matrix lookup table
Edge3 contractedEdgeEndpoints = new Edge3(edgeToContract.prevEdge.v.position, edgeToContract.v.position);
//Contract edge
HashSet <HalfEdge3> edgesPointingToNewVertex = halfEdgeMeshData.ContractTriangleHalfEdge(edgeToContract, smallestErrorEdge.mergePosition);
//timer.Stop();
//
// Remove all QEM_edges that belonged to the faces we contracted
//
//This is not needed if we check if an edge in the triangle has already been contracted
/*
* //timer.Start();
*
* //This edge doesnt exist anymore, so remove it from the lookup
* halfEdge_QEM_Lookup.Remove(edgeToContract);
*
* //Remove the two edges that were a part of the triangle of the edge we contracted
* RemoveHalfEdgeFromQEMEdges(edgeToContract.nextEdge, QEM_edges, halfEdge_QEM_Lookup);
* RemoveHalfEdgeFromQEMEdges(edgeToContract.nextEdge.nextEdge, QEM_edges, halfEdge_QEM_Lookup);
*
* //Remove the three edges belonging to the triangle on the opposite side of the edge we contracted
* //If there was an opposite side...
* if (edgeToContract.oppositeEdge != null)
* {
* HalfEdge3 oppositeEdge = edgeToContract.oppositeEdge;
*
* RemoveHalfEdgeFromQEMEdges(oppositeEdge, QEM_edges, halfEdge_QEM_Lookup);
* RemoveHalfEdgeFromQEMEdges(oppositeEdge.nextEdge, QEM_edges, halfEdge_QEM_Lookup);
* RemoveHalfEdgeFromQEMEdges(oppositeEdge.nextEdge.nextEdge, QEM_edges, halfEdge_QEM_Lookup);
* }
* //timer.Stop();
*/
//Remove the edges start and end vertices from the pos-matrix lookup table
qMatrices.Remove(contractedEdgeEndpoints.p1);
qMatrices.Remove(contractedEdgeEndpoints.p2);
//timer.Stop();
//
// Update all QEM_edges that is now connected with the new contracted vertex because their errors have changed
//
//The contracted position has a new Q matrix
Matrix4x4 QNew = MeshSimplification_QEM.CalculateQMatrix(edgesPointingToNewVertex, normalizeTriangles);
//Add the Q matrix to the pos-matrix lookup table
qMatrices.Add(smallestErrorEdge.mergePosition, QNew);
//Update the error of the QEM_edges of the edges that pointed to and from one of the two old Q matrices
//Those edges are the same edges that points to the new vertex and goes from the new vertex
//timer.Start();
foreach (HalfEdge3 edgeToV in edgesPointingToNewVertex)
{
//The edge going from the new vertex is the next edge of the edge going to the vertex
HalfEdge3 edgeFromV = edgeToV.nextEdge;
//To
QEM_Edge QEM_edgeToV = halfEdge_QEM_Lookup[edgeToV];
Edge3 edgeToV_endPoints = QEM_edgeToV.GetEdgeEndPoints();
Matrix4x4 Q1_edgeToV = qMatrices[edgeToV_endPoints.p1];
Matrix4x4 Q2_edgeToV = QNew;
QEM_edgeToV.UpdateEdge(edgeToV, Q1_edgeToV, Q2_edgeToV);
sorted_QEM_edges.UpdateItem(QEM_edgeToV);
//From
QEM_Edge QEM_edgeFromV = halfEdge_QEM_Lookup[edgeFromV];
Edge3 edgeFromV_endPoints = QEM_edgeFromV.GetEdgeEndPoints();
Matrix4x4 Q1_edgeFromV = QNew;
Matrix4x4 Q2_edgeFromV = qMatrices[edgeFromV_endPoints.p2];
QEM_edgeFromV.UpdateEdge(edgeFromV, Q1_edgeFromV, Q2_edgeFromV);
sorted_QEM_edges.UpdateItem(QEM_edgeFromV);
}
//timer.Stop();
//PAUSE FOR VISUALIZATION
//Display what we have so far
controller.DisplayMeshMain(halfEdgeMeshData.faces);
controller.displayStuffUI.text = "Triangles: " + halfEdgeMeshData.faces.Count.ToString();
yield return(new WaitForSeconds(0.02f));
}
}
//Called from editor script
public void GenerateHull()
{
//Get random points in 3d space
HashSet <Vector3> points_Unity = TestAlgorithmsHelpMethods.GenerateRandomPoints3D(seed, halfMapSize, numberOfPoints);
//HashSet<Vector3> points_Unity = GetCubeTestPoints();
//Points from a mesh
/*
* Transform meshTrans = constructHullFromThisMesh.transform;
*
* List<Vector3> vertices = new List<Vector3>(constructHullFromThisMesh.sharedMesh.vertices);
*
* //Local to global space
* List<Vector3> verticesGlobal = vertices.Select(x => meshTrans.TransformPoint(x)).ToList();
*
* HashSet<Vector3> points_Unity = new HashSet<Vector3>(verticesGlobal);
*/
//To stress-test these algorithms, generate points on a sphere because all of those should be on the hull
//HashSet<Vector3> points_Unity = TestAlgorithmsHelpMethods.GenerateRandomPointsOnSphere(seed, radius: 1f, numberOfPoints);
//To MyVector3
HashSet <MyVector3> points = new HashSet <MyVector3>(points_Unity.Select(x => x.ToMyVector3()));
//Normalize
Normalizer3 normalizer = new Normalizer3(new List <MyVector3>(points));
HashSet <MyVector3> points_normalized = normalizer.Normalize(points);
//
// Generate the convex hull
//
//Algorithm 1. Iterative algorithm
System.Diagnostics.Stopwatch timer = new System.Diagnostics.Stopwatch();
timer.Start();
HalfEdgeData3 convexHull_normalized = _ConvexHull.Iterative_3D(points_normalized, removeUnwantedTriangles, normalizer);
timer.Stop();
Debug.Log($"Generated a 3d convex hull in {timer.ElapsedMilliseconds / 1000f} seconds with {convexHull_normalized.faces.Count} triangles");
//
// Display
//
//Points
//TestAlgorithmsHelpMethods.DisplayPoints(points_Unity, 0.01f, Color.black);
//Hull mesh
if (convexHull_normalized != null)
{
HalfEdgeData3 convexHull = normalizer.UnNormalize(convexHull_normalized);
MyMesh myMesh = convexHull.ConvertToMyMesh("convex hull", MyMesh.MeshStyle.HardEdges);
//To unity mesh
Mesh convexHullMesh = myMesh.ConvertToUnityMesh(generateNormals: false, myMesh.meshName);
//Using gizmos to display mesh in 3d space gives a bad result
//TestAlgorithmsHelpMethods.DisplayMeshWithRandomColors(convexHullMesh, 0);
//Better to add it to a gameobject
//Use Shaded Wireframe to see the triangles
meshFilter.mesh = convexHullMesh;
//Points on the hull
//These are shining thorugh the mesh
//TestAlgorithmsHelpMethods.DisplayMeshCorners(convexHullMesh, 0.01f, Color.black);
}
}