/// <summary>
/// Optimizes navmesh by deleting some triangles
/// </summary>
/// <param name="itm"></param>
public IEnumerator OptimizeMesh()
{
C5.HashSet <Vector3> open = new C5.HashSet <Vector3>();
C5.HashSet <Triangle> openT = new C5.HashSet <Triangle>();
open.AddAll(vertex2Triangle.Keys);
while (!open.IsEmpty) //loop through all vertices
{
Vector3 current = open.Pop();
if (vertex2Triangle[current].Count < 3) //if less than 3, they cannot form a "circle"
{
continue;
}
openT.Clear();
openT.AddAll(vertex2Triangle[current]);
//Debug.Log("Opening " + current);
//start at arbitrary triangle
C5.IList <Triangle> circle = new C5.ArrayList <Triangle>();
circle.Add(openT.Pop());
//find connected circle
while (openT.Count > 0)
{
Triangle[] circleElement = openT.Intersect(triangleIncidence[circle.Last]).ToArray();
if (circleElement.Length < 1) //no candidate - break
{
break;
}
circle.Add(circleElement[0]);
openT.Remove(circle.Last);
}
if (openT.Count == 0 && triangleIncidence[circle.Last].Contains(circle.First))
{
//Debug.Log( "Unbroken: "+current );
//check height differences
bool isFlatEnough = true;
foreach (Triangle trg in vertex2Triangle[current])
{
foreach (Vector3 vct in trg.vertices)
{
if (Mathf.Abs(vct.y - current.y) > maxHeightDifference)
{
isFlatEnough = false;
}
}
}
if (!isFlatEnough)
{
continue;
}
ArrayList <Vector3> vctList = new ArrayList <Vector3>();
//remove old triangles
foreach (Triangle trg in circle) //ToArray() is to create a buffer (to prevent concurrent modification)
{
RemoveTriangle(trg);
for (int i = 0; i < 3; i++)
{
//find the CURRENT vertex - the one that is beeing removed
if (trg.vertices[i] == current)
{
//add the NEXT to the list
vctList.Add(trg.vertices[(i + 1) % 3]);
}
}
}
if (Outline.IsClockwise(vctList))
{
vctList.Reverse();
}
//build new triangles and add them
foreach (IEnumerable <int> newTriangles in Utils.TriangulatePolygon(vctList, Enumerable.Range(0, vctList.Count)).Chunks(3))
{
Triangle newTriag = new Triangle(newTriangles.Select(x => vctList[x]).ToArray());
AddTriangleByReference(newTriag);
}
//reopen used vertices
//open.AddAll(vctList); - maybe not necessary????
//yield return new WaitForSeconds(1);
yield return(null);
}
}
}
public IEnumerable <Mesh> ExtractMeshes()
{
List <Mesh> meshes = new List <Mesh>();
C5.HashSet <Triangle> untouched = new C5.HashSet <Triangle>();
untouched.AddAll(triangleIncidence.Keys);
Queue <Triangle> open = new Queue <Triangle>();
//the mesh that is beeing built
List <Vector3> vertices = new List <Vector3>();
Dictionary <Vector3, int> vertexToIndex = new Dictionary <Vector3, int>();
List <int> indices = new List <int>();
while (!untouched.IsEmpty)
{
if (open.Count == 0) //empty - open on a new slot
{
open.Enqueue(untouched.First());
untouched.Remove(open.First());
}
if (vertices.Count > 60000) //too many - split meshes
{
Mesh msh = new Mesh();
msh.vertices = vertices.ToArray();
msh.triangles = indices.ToArray();
meshes.Add(msh);
vertices.Clear();
vertexToIndex.Clear();
indices.Clear();
}
//one step of BFS
Triangle current = open.Dequeue();
foreach (Triangle expand in triangleIncidence[current])
{
if (untouched.Contains(expand))
{
open.Enqueue(expand);
untouched.Remove(expand);
}
}
//add to mesh
for (int i = 0; i < 3; i++)
{
if (vertexToIndex.ContainsKey(current.vertices[i]))
{
indices.Add(vertexToIndex[current.vertices[i]]);
}
else
{
vertices.Add(current.vertices[i]);
vertexToIndex[current.vertices[i]] = vertices.Count - 1;
indices.Add(vertices.Count - 1);
}
}
}
//buuild last mesh
Mesh msh2 = new Mesh();
msh2.vertices = vertices.ToArray();
msh2.triangles = indices.ToArray();
meshes.Add(msh2);
return(meshes);
}