/**
* Build neighbourly relations between vertices and wedges using the triangles of the model
**/
private void BuildNeighbourlyRelations(List <Wedge> wedges, Vertex[] vertices, int[] tris)
{
for (int i = 0; i != tris.Length; i += 3)
{
Vertex v0 = vertices[tris[i]];
Vertex v1 = vertices[tris[i + 1]];
Vertex v2 = vertices[tris[i + 2]];
Triangle triangle = new Triangle(v0, v1, v2);
//Set this triangle as an adjacent triangle for every vertex
v0.AddAdjacentTriangle(triangle);
v1.AddAdjacentTriangle(triangle);
v2.AddAdjacentTriangle(triangle);
Wedge w0 = GetWedgeHoldingVertex(wedges, v0);
Wedge w1 = GetWedgeHoldingVertex(wedges, v1);
Wedge w2 = GetWedgeHoldingVertex(wedges, v2);
w0.AddNeighbor(w1);
w0.AddNeighbor(w2);
w1.AddNeighbor(w0);
w1.AddNeighbor(w2);
w2.AddNeighbor(w0);
w2.AddNeighbor(w1);
}
}
public void AddNeighbor(Wedge neighbor)
{
if (!HasNeighbor(neighbor))
{
m_neighbors.Add(neighbor);
}
}
private void BuildWedges(List <Wedge> wedges, List <Vector3> verts, List <int> tris)
{
Vertex[] vertices = new Vertex[verts.Count];
//First sort vertices into wedges
for (int i = 0; i != verts.Count; i++)
{
Vertex vertex = new Vertex(verts[i], i);
vertices[i] = vertex;
Wedge wedge = WedgeForPosition(wedges, verts[i]);
if (wedge != null)
{
wedge.AddVertex(vertex);
}
else
{
wedge = new Wedge(verts[i], wedges.Count);
wedge.AddVertex(vertex);
wedges.Add(wedge);
}
}
//Build neighbourly relations between vertices and wedges using the triangles of the model
BuildNeighbourlyRelations(wedges, vertices, tris);
//Determine which triangles are adjacent to each wedge
//for (int i = 0; i != m_wedges.Count; i++)
//{
// m_wedges[i].InvalidateAdjacentTriangles();
//}
}
public void RemoveNeighbor(Wedge neighbor)
{
if (HasNeighbor(neighbor))
{
m_neighbors.Remove(neighbor);
}
}
} // orthogonal unit vector
public WedgeTriangle(Wedge w0, Wedge w1, Wedge w2)
{
m_wedges = new Wedge[3];
m_wedges[0] = w0;
m_wedges[1] = w1;
m_wedges[2] = w2;
ComputeNormal();
}
/**
* Collapse all vertices in this wedge using the m_mappedVertices list
**/
public void CollapseOnWedge(Wedge w)
{
//w = m_collapse;
//collapsed vertices
Vertex[] collapseVertices = new Vertex[m_collapsedVertices.Count];
int collapseVertexIdx = 0;
foreach (KeyValuePair <int, int> kvp in m_collapsedVertices)
{
Vertex vertex = GetVertexForID(kvp.Key);
Vertex collapseVertex = w.GetVertexForID(kvp.Value);
vertex.CollapseOnWedgeVertex(collapseVertex);
collapseVertices[collapseVertexIdx] = collapseVertex;
collapseVertexIdx++;
}
for (int i = 0; i != collapseVertices.Length; i++)
{
Vertex collapseVertex = collapseVertices[i];
//the collapse vertex does not have any adjacent triangles even after collapsing operation, delete it
if (collapseVertex.AdjacentTriangles.Count == 0)
{
w.RemoveVertex(collapseVertex);
this.m_deletedVertices.Add(collapseVertex.ID);
}
}
//for (int i = 0; i != m_collapsedVertices.Count; i++)
//{
// Vertex vertex = GetVertexForID(m_collapsedVertices[i].m_initialIndex);
// //if (vertex != null) //vertex has been deleted
// Vertex collapseVertex = w.GetVertexForID(m_collapsedVertices[i].m_collapsedIndex);
// vertex.CollapseOnWedgeVertex(collapseVertex);
// //the collapse vertex does not have any adjacent triangles even after collapsing operation, delete it
// if (collapseVertex.AdjacentTriangles.Count == 0)
// {
// w.RemoveVertex(collapseVertex);
// this.m_deletedVertices.Add(collapseVertex.ID);
// }
//}
//displaced vertices
for (int i = 0; i != m_displacedVertices.Count; i++)
{
Vertex vertex = GetVertexForID(m_displacedVertices[i].m_index);
//if (vertex != null)
w.AddVertex(vertex);
this.RemoveVertex(vertex);
}
}
/**
* Compute the cost to collapse a specific edge defined by vertices u and v
* **/
private float ComputeEdgeCollapseCost(Wedge u, Wedge v)
{
// if we collapse edge uv by moving u to v then how
// much different will the model change, i.e. how much "error".
// Texture, vertex normal, and border vertex code was removed
// to keep this demo as simple as possible.
// The method of determining cost was designed in order
// to exploit small and coplanar regions for
// effective polygon reduction.
// Is is possible to add some checks here to see if "folds"
// would be generated. i.e. normal of a remaining face gets
// flipped. I never seemed to run into this problem and
// therefore never added code to detect this case.
int i;
float edgelength = (v.m_position - u.m_position).magnitude;
float curvature = 0;
// find the "sides" triangles that are on the edge uv
List <WedgeTriangle> sides = u.GetSharedTrianglesWithWedge(v);
if (sides.Count < 2) //wedge u cannot be collapsed on v because this edge is non manifold (i.e does not have 2 adjacent triangle)
{
return(-1); //return a negative/invalid cost
}
// use the triangle facing most away from the sides
// to determine our curvature term
for (i = 0; i < u.AdjacentTriangles.Count; i++)
{
Vector3 n1 = u.AdjacentTriangles[i].m_normal;
float mincurv = 1; // curve for face i and closer side to it
for (int j = 0; j < sides.Count; j++)
{
// use dot product of face normals
Vector3 n2 = sides[j].m_normal;
float dotprod;
if (n1 == n2)
{
dotprod = 1;
}
else
{
dotprod = n1.x * n2.x + n1.y * n2.y + n1.z * n2.z;
}
mincurv = Mathf.Min(mincurv, (1 - dotprod) / 2.0f);
}
curvature = Mathf.Max(curvature, mincurv);
}
//Debug.Log("cost between " + u.ID + " and " + v.ID + " is " + edgelength * curvature);
// the more coplanar the lower the curvature term
return(edgelength * curvature);
}
public void Delete()
{
for (int i = 0; i < 3; i++)
{
Wedge wedge = m_wedges[i];
if (wedge != null)
{
wedge.RemoveAdjacentTriangle(this);
}
}
}
public void ReplaceWedge(Wedge vOld, Wedge vNew)
{
for (int i = 0; i != 3; i++)
{
if (vOld == m_wedges[i])
{
m_wedges[i] = vNew;
}
}
vNew.AddAdjacentTriangle(this);
ComputeNormal();
}
/**
* Core function of the algorithm
* **/
private void ProgressiveMesh(ModelData data, out int[] map, out int[] permutation)
{
PrepareMeshData(data.Verts, data.Tris);
ComputeAllEdgeCollapseCosts();
//for (int i = 0; i != m_wedges.Count; i++)
//{
// Wedge mn = m_wedges[i];
// if (mn.m_collapse != null)
// Debug.Log("wedge " + mn.ID + " costs " + mn.m_cost + " to collapse on " + mn.m_collapse.ID);
//}
map = new int[m_wedges.Count];
permutation = new int[m_wedges.Count];
// reduce the object down to nothing
while (m_wedges.Count > 0)
{
// get the next vertex to collapse
Wedge mn = MinimumCostEdge();
// keep track of this vertex, i.e. the collapse ordering
permutation[mn.ID] = m_wedges.Count - 1;
// keep track of vertex to which we collapse to
map[m_wedges.Count - 1] = (mn.m_collapse != null) ? mn.m_collapse.ID : -1;
// Collapse this edge
Collapse(mn, mn.m_collapse);
//if (mn.m_collapse != null)
// Debug.Log("Wedge " + mn.ID + " collapses on wedge " + mn.m_collapse.ID + " with cost " + mn.m_cost);
//first time we encounter a wedge that cannot collapse, we store here the count of remaining wedges including the one we just try to collapse
if (mn.m_collapse == null && m_minRendereWedgesCount <= 3)
{
m_minRendereWedgesCount = m_wedges.Count + 1;
}
}
// reorder the map list based on the collapse ordering
for (int i = 0; i < map.Length; i++)
{
//map[i] = (map[i] == -1) ? 0 : permutation[map[i]];
if (map[i] >= 0)
{
map[i] = permutation[map[i]];
}
}
}
/**
* Build neighbourly relations between vertices and wedges using the triangles of the model
**/
private void BuildNeighbourlyRelations(List <Wedge> wedges, Vertex[] vertices, List <int> tris)
{
for (int i = 0; i != tris.Count; i += 3)
{
Vertex v0 = vertices[tris[i]];
Vertex v1 = vertices[tris[i + 1]];
Vertex v2 = vertices[tris[i + 2]];
Triangle triangle = new Triangle(v0, v1, v2);
//m_triangles.Add(triangle);
//Set this triangle as an adjacent triangle for every vertex
//v0.AddAdjacentTriangle(triangle);
//v1.AddAdjacentTriangle(triangle);
//v2.AddAdjacentTriangle(triangle);
//for each triangle vertex, set the 2 opposite points as neighbors
//v0.AddNeighbor(v1);
//v0.AddNeighbor(v2);
//v1.AddNeighbor(v0);
//v1.AddNeighbor(v2);
//v2.AddNeighbor(v0);
//v2.AddNeighbor(v1);
Wedge w0 = GetWedgeHoldingVertex(wedges, v0);
Wedge w1 = GetWedgeHoldingVertex(wedges, v1);
Wedge w2 = GetWedgeHoldingVertex(wedges, v2);
w0.AddNeighbor(w1);
w0.AddNeighbor(w2);
w1.AddNeighbor(w0);
w1.AddNeighbor(w2);
w2.AddNeighbor(w0);
w2.AddNeighbor(w1);
WedgeTriangle wedgeTriangle = new WedgeTriangle(w0, w1, w2);
wedgeTriangle.m_mappedVertexTriangle = triangle; //map here the vertex triangle to the wedge triangle
if (wedges == m_initialWedges) //populate the m_originalTriangles using the m_initialWedges list only
{
m_originalTriangles.Add(wedgeTriangle);
}
w0.AddAdjacentTriangle(wedgeTriangle);
w1.AddAdjacentTriangle(wedgeTriangle);
w2.AddAdjacentTriangle(wedgeTriangle);
}
}
/**
* Collapse the wedge u onto the wedge v
* **/
private void Collapse(Wedge u, Wedge v)
{
//Collapse the edge uv by moving wedge u onto v
// Actually remove tris on uv, then update tris that
// have u to have v, and then remove u.
if (v == null)
{
// u is a vertex all by itself so just delete it
u.Delete();
m_wedges.Remove(u);
return;
}
// delete triangles on edge uv:
List <WedgeTriangle> uvSharedTriangles = u.GetSharedTrianglesWithWedge(v);
for (int i = 0; i != uvSharedTriangles.Count; i++)
{
uvSharedTriangles[i].Delete();
}
// update remaining triangles to have v instead of u
for (int i = 0; i != u.AdjacentTriangles.Count; i++)
{
u.AdjacentTriangles[i].ReplaceWedge(u, v);
}
//add u neighbors to v and add v as a new neighbor of u neighbors
for (int i = 0; i != u.Neighbors.Count; i++)
{
if (u.Neighbors[i] != v)
{
v.AddNeighbor(u.Neighbors[i]);
u.Neighbors[i].AddNeighbor(v);
}
}
u.Delete();
m_wedges.Remove(u);
// recompute the edge collapse costs for neighboring vertices
for (int i = 0; i < u.Neighbors.Count; i++)
{
ComputeEdgeCostAtWedge(u.Neighbors[i]);
}
}
/**
* Tell if this vertex can collapse on one of the vertices of the parameter 'wedge'
* Return the Vertex on which this vertex can collapse on
**/
public Vertex FindVertexToCollapseOn(Wedge wedge)
{
if (wedge == null)
{
return(null);
}
for (int i = 0; i != wedge.Vertices.Count; i++)
{
if (wedge.Vertices[i].ShareTriangleWithVertex(this))
{
return(wedge.Vertices[i]);
}
}
return(null);
}
/**
* Return the triangles shared by two wedges.
**/
public List <WedgeTriangle> GetSharedTrianglesWithWedge(Wedge wedge)
{
List <WedgeTriangle> sharedTriangles = new List <WedgeTriangle>();
for (int i = 0; i < m_adjacentTriangles.Count; i++)
{
for (int j = 0; j != wedge.m_adjacentTriangles.Count; j++)
{
if (m_adjacentTriangles[i] == wedge.m_adjacentTriangles[j])
{
sharedTriangles.Add(m_adjacentTriangles[i]);
}
}
}
return(sharedTriangles);
}
/**
* Core function of the algorithm
* **/
private void ProgressiveMesh(ModelData data, out int[] map, out int[] permutation)
{
PrepareMeshData(data);
ComputeAllEdgeCollapseCosts();
//int[] mapArray = new int[m_wedges.Count]; // allocate space
//int[] permutationArray = new int[m_wedges.Count]; // allocate space
map = new int[m_wedges.Count];
permutation = new int[m_wedges.Count];
// reduce the object down to nothing
while (m_wedges.Count > 0)
{
// get the next vertex to collapse
Wedge mn = MinimumCostEdge();
//if (mn.m_collapse != null)
// Debug.Log("collapsing wedge " + mn.ID + " on wedge " + mn.m_collapse.ID + " with cost " + mn.m_cost);
// keep track of this vertex, i.e. the collapse ordering
permutation[mn.ID] = m_wedges.Count - 1;
// keep track of vertex to which we collapse to
map[m_wedges.Count - 1] = (mn.m_collapse != null) ? mn.m_collapse.ID : -1;
// Collapse this edge
Collapse(mn, mn.m_collapse);
//copy mapped, displaced and deleted vertices to the wedge that will remain alive
Wedge persistentWedge = WedgeForID(m_initialWedges, mn.ID);
persistentWedge.m_collapsedVertices = mn.m_collapsedVertices;
persistentWedge.m_displacedVertices = mn.m_displacedVertices;
persistentWedge.m_deletedVertices = mn.m_deletedVertices;
}
// reorder the map list based on the collapse ordering
for (int i = 0; i < map.Length; i++)
{
//map[i] = (map[i] == -1) ? 0 : permutation[map[i]];
if (map[i] >= 0)
{
map[i] = permutation[map[i]];
}
}
}
private void BuildWedges(List <Wedge> wedges, ModelData data)
{
Vertex[] vertices = new Vertex[data.Verts.Length];
//First sort vertices into wedges
for (int i = 0; i != data.Verts.Length; i++)
{
Vertex vertex = new Vertex(data.Verts[i], i);
if (data.Colors != null && data.Colors.Length > 0)
{
vertex.m_color = data.Colors[i];
}
if (data.UVs != null && data.UVs.Length > 0)
{
vertex.m_uv = data.UVs[i];
}
vertices[i] = vertex;
Wedge wedge = WedgeForPosition(wedges, data.Verts[i]);
if (wedge != null)
{
wedge.AddVertex(vertex);
}
else
{
wedge = new Wedge(data.Verts[i], wedges.Count);
wedge.AddVertex(vertex);
wedges.Add(wedge);
}
}
//Build neighbourly relations between vertices and wedges using the triangles of the model
BuildNeighbourlyRelations(wedges, vertices, data.Tris);
//Determine which triangles are adjacent to each wedge
for (int i = 0; i != m_wedges.Count; i++)
{
m_wedges[i].InvalidateAdjacentTriangles();
}
}
/**
* Compute the cost to collapse a specific edge to one of its neighbors (the one with the least cost is chosen)
* **/
private void ComputeEdgeCostAtWedge(Wedge w)
{
// compute the edge collapse cost for all edges that start
// from vertex v. Since we are only interested in reducing
// the object by selecting the min cost edge at each step, we
// only cache the cost of the least cost edge at this vertex
// (in member variable collapse) as well as the value of the
// cost (in member variable objdist).
if (w.Neighbors.Count == 0)
{
// v doesn't have neighbors so it costs nothing to collapse
w.m_collapse = null;
w.m_cost = 0;
return;
}
w.m_cost = 1000000;
w.m_collapse = null;
// search all neighboring edges for "least cost" edge
for (int i = 0; i < w.Neighbors.Count; i++)
{
float dist;
dist = ComputeEdgeCollapseCost(w, w.Neighbors[i]);
if (dist < 0) //non-manifold edge
{
w.m_collapse = null;
w.m_cost = 0;
}
else
{
if (dist < w.m_cost)
{
w.m_collapse = w.Neighbors[i]; // candidate for edge collapse
w.m_cost = dist; // cost of the collapse
}
}
}
}
/**
* Return the vertex with the 'least cost' to collapse
* **/
private Wedge MinimumCostEdge()
{
// Find the edge that when collapsed will affect model the least.
// This funtion actually returns a Vertex, the second vertex
// of the edge (collapse candidate) is stored in the vertex data.
// Serious optimization opportunity here: this function currently
// does a sequential search through an unsorted list :-(
// Our algorithm could be O(n*lg(n)) instead of O(n*n)
Wedge mn = null;
float minCost = float.MaxValue;
for (int i = 0; i < m_wedges.Count; i++)
{
if (m_wedges[i].m_collapse == null)
{
continue;
}
if (m_wedges[i].m_cost == 0) //zero cost, take the first wedge we encounter
{
return(m_wedges[i]);
}
if (m_wedges[i].m_cost < minCost)
{
mn = m_wedges[i];
minCost = m_wedges[i].m_cost;
}
}
if (mn == null) //we spent all wedges that collapse, only wedges with null collapse remain so return the first one
{
mn = m_wedges[0];
}
return(mn);
}
public bool HasNeighbor(Wedge neighbor)
{
return(m_neighbors.Contains(neighbor));
}
/**
* Return a list of vertices and indices where player has specified a maximum count of vertices for the initial model
**/
public void CutMeshPolygons(out ModelData cutData, int maxWedges, bool bStopWatch = false)
{
//no work to do here
if (maxWedges >= m_initialWedges.Count)
{
cutData = m_data;
return;
}
//list of vertices deleted during the process of collapsing
//System.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();
//sw.Start();
//int counter = 0;
//while (counter < 1E04)
//{
// FindDeletedVertices(maxWedges);
// counter++;
//}
//sw.Stop();
//Debug.Log("V1 took " + sw.ElapsedMilliseconds + " ms");
//sw = new System.Diagnostics.Stopwatch();
//sw.Start();
//counter = 0;
//while (counter < 1E04)
//{
// FindDeletedVertices2(maxWedges);
// counter++;
//}
//sw.Stop();
//Debug.Log("V2 took " + sw.ElapsedMilliseconds + " ms");
System.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();
if (bStopWatch)
{
sw = new System.Diagnostics.Stopwatch();
sw.Start();
}
//List<int> deletedVertices = FindDeletedVertices(maxWedges);
int[] deletedVertices = FindDeletedVertices(maxWedges);
//list of vertices displaced during the process of collapsing
List <DisplacedVertex> displacedVertices = FindDisplacedVertices(maxWedges);
//map vertices that have collapsed
List <CollapsedVertex> collapsedVertices = MapVertices(maxWedges);
//copy IDs of collapsed and deleted vertices into an array and sort it by ascending order
int[] dismissedVerticesIDs = new int[collapsedVertices.Count + deletedVertices.Length];
for (int i = 0; i != collapsedVertices.Count; i++)
{
dismissedVerticesIDs[i] = collapsedVertices[i].m_initialIndex;
}
for (int i = collapsedVertices.Count; i != dismissedVerticesIDs.Length; i++)
{
dismissedVerticesIDs[i] = deletedVertices[i - collapsedVertices.Count];
}
if (dismissedVerticesIDs.Length > 1)
{
System.Array.Sort(dismissedVerticesIDs);
}
if (bStopWatch)
{
sw.Stop();
Debug.Log("STEP1 took " + sw.ElapsedMilliseconds + " ms");
}
if (bStopWatch)
{
sw = new System.Diagnostics.Stopwatch();
sw.Start();
}
//Traverse wedges (untouched and collapsed ones) and fill in the vertices array by shifting one vertex according to the previous sorted array
Vertex[] cutVertices = new Vertex[m_data.Verts.Length];
int maxID = -1;
for (int i = 0; i != m_initialWedges.Count; i++)
{
Wedge wedge = m_initialWedges[i];
for (int j = 0; j != wedge.Vertices.Count; j++)
{
Vertex vertex = wedge.Vertices[j];
//create a copy of this vertex to maintain intact the original one
Vertex copiedVertex = new Vertex();
copiedVertex.m_position = vertex.m_position;
copiedVertex.ID = vertex.ID;
copiedVertex.m_color = vertex.m_color;
copiedVertex.m_uv = vertex.m_uv;
//test if the vertex collapsed or has been deleted
bool bDismissVertex = false;
for (int p = 0; p != dismissedVerticesIDs.Length; p++)
{
if (dismissedVerticesIDs[p] == copiedVertex.ID)
{
bDismissVertex = true;
}
}
if (!bDismissVertex)
{
//test if it has been displaced and update its position accordingly
for (int p = 0; p != displacedVertices.Count; p++)
{
if (displacedVertices[p].m_index == copiedVertex.ID)
{
copiedVertex.m_position = displacedVertices[p].m_targetPosition;
break;
}
}
//compute the new id of this vertex and populate the new vertex array
int id = GetShiftedID(dismissedVerticesIDs, copiedVertex.ID);
if (id > maxID)
{
maxID = id;
}
if (cutVertices[id] == null)
{
cutVertices[id] = copiedVertex;
}
}
}
}
//use the maximum vertex index to crop the array
System.Array.Resize(ref cutVertices, maxID + 1);
if (bStopWatch)
{
sw.Stop();
Debug.Log("STEP2 took " + sw.ElapsedMilliseconds + " ms");
}
//now build the triangle list
List <int> triangles = new List <int>();
for (int i = 0; i != m_data.Tris.Length; i += 3)
{
int p0 = m_data.Tris[i];
int p1 = m_data.Tris[i + 1];
int p2 = m_data.Tris[i + 2];
//first check if all triangle vertices still exist
bool bDismissTriangle = false;
for (int p = 0; p != deletedVertices.Length; p++)
{
if (p0 == deletedVertices[p] || p1 == deletedVertices[p] || p2 == deletedVertices[p])
{
bDismissTriangle = true;
break;
}
}
if (bDismissTriangle)
{
continue;
}
//if this triangle is valid, find the correct ID for each vertex
p0 = GetShiftedID(dismissedVerticesIDs, GetCollapseIDForID(collapsedVertices, p0));
p1 = GetShiftedID(dismissedVerticesIDs, GetCollapseIDForID(collapsedVertices, p1));
p2 = GetShiftedID(dismissedVerticesIDs, GetCollapseIDForID(collapsedVertices, p2));
//one-dimensional (flat) triangle, dismiss it
if (p0 == p1 || p1 == p2 || p2 == p0)
{
continue;
}
//accumulate triangle normal for each vertex
Triangle triangle = new Triangle(cutVertices[p0], cutVertices[p1], cutVertices[p2]);
//cutVertices[p0].AccumulateNormalFromTriangle(triangle.m_normal);
//cutVertices[p1].AccumulateNormalFromTriangle(triangle.m_normal);
//cutVertices[p2].AccumulateNormalFromTriangle(triangle.m_normal);
triangles.Add(p0);
triangles.Add(p1);
triangles.Add(p2);
}
//extract data from the Vertex array
Vector3[] outputVertices = new Vector3[cutVertices.Length];
//Vector3[] outputNormals = new Vector3[cutVertices.Length];
Color[] outputColors = (m_data.Colors != null) ? new Color[cutVertices.Length] : null;
Vector2[] outputUVs = (m_data.UVs != null) ? new Vector2[cutVertices.Length] : null;
for (int i = 0; i != outputVertices.Length; i++)
{
//vertices
outputVertices[i] = cutVertices[i].m_position;
//normals
//outputNormals[i] = cutVertices[i].GetAccumulationNormal();
//colors
if (outputColors != null)
{
outputColors[i] = cutVertices[i].m_color;
}
//uv
if (outputUVs != null)
{
outputUVs[i] = cutVertices[i].m_uv;
}
}
cutData = new ModelData(outputVertices, triangles.ToArray());
//cutData.Normals = outputNormals;
cutData.Colors = outputColors;
cutData.UVs = outputUVs;
}
/**
* Map the vertices of all the wedges that have been cut down beyond the maxWedges limit
**/
private List <CollapsedVertex> MapVertices(int maxWedges)
{
List <CollapsedVertex> collapsedVertices = new List <CollapsedVertex>();
for (int i = m_initialWedges.Count - 1; i != maxWedges - 1; i--)
{
Wedge wedge = m_initialWedges[i];
List <Vertex> wedgeVerticesCopy = new List <Vertex>(wedge.Vertices);
for (int v = 0; v != wedgeVerticesCopy.Count; v++)
{
Wedge collapseWedge = wedge; //reset the wedge to the actual wedge holding this vertex
CollapsedVertex collapsedVertex = new CollapsedVertex(-1, -1);
Vertex vertex = wedgeVerticesCopy[v];
collapsedVertex.m_initialIndex = vertex.ID;
int stopIndex = 0;
while (collapseWedge.ID >= maxWedges && stopIndex < 100)
{
if (collapseWedge.m_collapse == null)
{
break;
}
//Vertex collapseVertex = vertex.FindVertexToCollapseOn(collapseWedge.m_collapse);
Vertex collapseVertex = collapseWedge.MapVertex(vertex);
if (collapseVertex != null)
{
vertex = collapseVertex;
collapsedVertex.m_collapsedIndex = collapseVertex.ID;
}
//collapseWedge = collapseWedge.m_collapse;
//int nextWedgeIndex = m_collapseMap[collapseWedge.ID];
//if (nextWedgeIndex >= 0)
// collapseWedge = m_initialWedges[m_collapseMap[collapseWedge.ID]];
//else
// break;
int nextWedgeIndex = m_collapseMap[collapseWedge.ID];
if (nextWedgeIndex == 0)
{
break;
}
else
{
collapseWedge = collapseWedge.m_collapse;
}
//if (collapseWedge != null)
//{
// //set the vertex position as the position of the last wedge it collapsed to or been moved to
// collapsedVertex.m_position = collapseWedge.m_position;
//}
stopIndex++;
}
if (stopIndex >= 99)
{
Debug.Log("stopIndex:" + stopIndex);
}
if (collapsedVertex.m_collapsedIndex >= 0)
{
collapsedVertices.Add(collapsedVertex);
}
}
}
return(collapsedVertices);
}
/**
* Collapse the wedge u onto the wedge v
* **/
private void Collapse(Wedge u, Wedge v)
{
// Collapse the edge uv by moving vertex u onto v
// Actually remove tris on uv, then update tris that
// have u to have v, and then remove u.
if (v == null)
{
// u is a vertex all by itself so just delete it
u.Delete();
m_wedges.Remove(u);
return;
}
//Find vertices that will collapse or be displaced
for (int i = 0; i != u.Vertices.Count; i++)
{
Vertex vertex = u.Vertices[i];
Vertex collapseVertex = vertex.FindVertexToCollapseOn(v); //the vertex it will collapse on if it exists
if (collapseVertex != null)
{
u.m_collapsedVertices.Add(vertex.ID, collapseVertex.ID); //no exception will be thrown as unique IDs are inserted into that dictionary
//CollapsedVertex collapsedVertex = new CollapsedVertex(vertex.ID, collapseVertex.ID);
//u.m_collapsedVertices.Add(collapsedVertex);
}
else
{
DisplacedVertex displacedVertex = new DisplacedVertex();
displacedVertex.m_index = vertex.ID;
displacedVertex.m_targetPosition = v.m_position;
u.m_displacedVertices.Add(displacedVertex);
}
}
//delete triangles on edge[u - v]
List <Triangle> sharedTriangles = u.GetSharedTrianglesWithWedge(v);
for (int i = 0; i != sharedTriangles.Count; i++)
{
//delete the triangle
sharedTriangles[i].Delete();
for (int j = 0; j != sharedTriangles[i].Vertices.Length; j++)
{
Vertex vertex = sharedTriangles[i].Vertices[j];
if (!u.HasVertex(vertex) && !v.HasVertex(vertex)) //the third wedge that is not u or v holds this vertex
{
if (vertex.AdjacentTriangles.Count == 0) //vertex is isolated, remove it
{
//find the wedge and remove the vertex from its internal list
GetWedgeHoldingVertex(m_wedges, vertex).RemoveVertex(vertex);
//add the vertex ID to the list of vertices deleted during the operation of collapsing u onto v
u.m_deletedVertices.Add(vertex.ID);
}
}
}
}
//perform the actual collapse
u.CollapseOnWedge(v);
//add u neighbors to v and add v as a new neighbor of u neighbors
for (int i = 0; i != u.Neighbors.Count; i++)
{
if (u.Neighbors[i] != v)
{
v.AddNeighbor(u.Neighbors[i]);
u.Neighbors[i].AddNeighbor(v);
}
}
//neighbors of wedge u are likely to have lost one triangle through one of their vertex so invalidate them
for (int i = 0; i != u.Neighbors.Count; i++)
{
u.Neighbors[i].InvalidateAdjacentTriangles();
}
//delete the wedge and remove it from global list
u.Delete();
m_wedges.Remove(u);
// recompute the edge collapse costs for neighboring wedges
for (int i = 0; i < u.Neighbors.Count; i++)
{
ComputeEdgeCostAtWedge(u.Neighbors[i]);
}
}
public bool HasWedge(Wedge w)
{
return(m_wedges[0] == w || m_wedges[1] == w || m_wedges[2] == w);
}
