public Vector3[] GenerateTriangleAdjacencyBuffer(Mesh mesh)
{
// dla kazdego trojkata - okresl adjacency
var adjacencyInfos = new List <AdjacencyInformation>();
var vertices = mesh.vertices;
var triangles = mesh.triangles;
var normals = mesh.normals;
var positionToIndexDict = vertices
.Select((v, i) => new { v, i })
.GroupBy(c => c.v)
.ToDictionary(
c => c.Key,
c => c.Select(k => k.i).ToList());
var indexToTriangleDict = triangles
.Select((v, i) => new { triangleIndex = i / 3, v })
.GroupBy(c => c.v)
.ToDictionary(c => c.Key, c => c.Select(k => k.triangleIndex).ToList());
for (int triangleIndex = 0; triangleIndex < triangles.Length / 3; triangleIndex++)
{
var index0 = triangles[triangleIndex * 3 + 0];
var vertex0 = vertices[index0];
var index1 = triangles[triangleIndex * 3 + 1];
var vertex1 = vertices[index1];
var index2 = triangles[triangleIndex * 3 + 2];
var vertex2 = vertices[index2];
var otherTrianglesOfVertex0 = FindOtherTrianglesOfVertex(positionToIndexDict, indexToTriangleDict, vertex0, triangleIndex);
var otherTrianglesOfVertex1 = FindOtherTrianglesOfVertex(positionToIndexDict, indexToTriangleDict, vertex1, triangleIndex);
var otherTrianglesOfVertex2 = FindOtherTrianglesOfVertex(positionToIndexDict, indexToTriangleDict, vertex2, triangleIndex);
AdjacencyInformation info = new AdjacencyInformation();
FillAdjacencyInformation(vertices, triangles, normals, otherTrianglesOfVertex0, otherTrianglesOfVertex1, triangleIndex, index0, index1, info, 0);
FillAdjacencyInformation(vertices, triangles, normals, otherTrianglesOfVertex1, otherTrianglesOfVertex2, triangleIndex, index1, index2, info, 1);
FillAdjacencyInformation(vertices, triangles, normals, otherTrianglesOfVertex2, otherTrianglesOfVertex0, triangleIndex, index2, index0, info, 2);
info.SetNormal(0, positionToIndexDict[vertex0].Select(i => normals[i]).Aggregate((sum, next) => sum + next).normalized);
info.SetNormal(1, positionToIndexDict[vertex1].Select(i => normals[i]).Aggregate((sum, next) => sum + next).normalized);
info.SetNormal(2, positionToIndexDict[vertex2].Select(i => normals[i]).Aggregate((sum, next) => sum + next).normalized);
adjacencyInfos.Add(info);
}
var buffer = new Vector3[adjacencyInfos.Count * 6];
for (int i = 0; i < adjacencyInfos.Count; i++)
{
adjacencyInfos[i].WriteToBuffer(buffer, i);
}
return(buffer);
}
private static void FillAdjacencyInformation(Vector3[] vertices, int[] triangles, Vector3[] normals,
List <int> otherTrianglesOfVertexA, List <int> otherTrianglesOfVertexB, int triangleIndex,
int indexA, int indexB, AdjacencyInformation info, int indexInInfo)
{
var commonTrianglesOfEdge0 = otherTrianglesOfVertexA.Intersect(otherTrianglesOfVertexB).ToList();
if (commonTrianglesOfEdge0.Count > 1)
{
Debug.Log("W139 More than one common triangles of edge of triangle ");
}
if (commonTrianglesOfEdge0.Count == 0)
{
Debug.Log("W138 No common triangles at edge of triangle");
info.SetPosition(indexInInfo, Vector3.negativeInfinity);
}
else
{
var adjacentTriangle = commonTrianglesOfEdge0[0];
var tv = new List <int>()
{
triangles[adjacentTriangle * 3 + 0],
triangles[adjacentTriangle * 3 + 1],
triangles[adjacentTriangle * 3 + 2],
}.Select(c => new { v = c, pos = vertices[c] })
.Where(c => c.pos != vertices[indexA] && c.pos != vertices[indexB])
.ToList();
if (tv.Count != 1)
{
Debug.Log("W135 TV list has not one but " + tv.Count);
info.SetPosition(indexInInfo, Vector3.negativeInfinity);
}
else
{
var thirdVertex = tv.First().v;
info.SetPosition(indexInInfo, vertices[thirdVertex]);
}
}
}