//Return a unity mesh in a left-handed coordinate system
public UnityMesh ToUnityMesh()
{
UnityMesh result = new UnityMesh(this.Name, this.UniqueIdentifier);
Vector3[] vertices = new Vector3[VertexList.Length];
//Flip z component of all Vector3 in vertex list
for (int i = 0; i < VertexList.Length; i++)
{
vertices[i] = new Vector3(VertexList[i].x, VertexList[i].y, -VertexList[i].z);
}
result.VertexList = vertices;
Vector3[] normals = new Vector3[NormalList.Length];
//Flip z component of all Vector3 in normal list
for (int i = 0; i < NormalList.Length; i++)
{
normals[i] = new Vector3(NormalList[i].x, NormalList[i].y, -NormalList[i].z);
}
result.NormalList = normals;
int[] triangles = new int[TriangleList.Length];
//Flip the order of triangle vertices. v0,v1,v2 -> v0,v2,v1.
for (int i = 0; i < TriangleList.Length; i += 3)
{
triangles[i] = TriangleList[i];
triangles[i + 1] = TriangleList[i + 2];
triangles[i + 2] = TriangleList[i + 1];
}
result.TriangleList = triangles;
return(result);
}
//Creates a list of lists with BlenderMeshes. The inner list contains multipe BlenderMeshes for one object with max. 2^16 vertices, because of Unitys limitation.
public static List <List <UnityMesh> > createSubmeshesForUnity(List <BlenderMesh> blenderMesh)
{
List <List <UnityMesh> > result = new List <List <UnityMesh> >();
//Iterate all complete meshes found in file
foreach (BlenderMesh completeBlenderMesh in blenderMesh)
{
UnityMesh completeMesh = completeBlenderMesh.ToUnityMesh();
List <UnityMesh> outterListElement = new List <UnityMesh>();
result.Add(outterListElement);
int maxVerts = 6000;//65534; //TODO ? magic number, performs well
int positionTriangleList = 0;
//Go over the complete triangle list of mesh
while (positionTriangleList < completeMesh.TriangleList.Length)
{
UnityMesh newMesh = new UnityMesh(completeMesh.Name, completeMesh.UniqueIdentifier); //Create submesh
outterListElement.Add(newMesh);
List <Vector3> vertList = new List <Vector3>(); //Create vertices list for submesh
List <Vector3> normList = new List <Vector3>(); //Create normal list for submesh
List <int> triangles = new List <int>(); //Create triangle list for submesh
int[] findVertexIndex = new int[completeMesh.VertexList.Length]; //for optimization, key: vertex index of complete mesh, value: vertex index of new mesh
for (int i = 0; i < findVertexIndex.Length; i++) //memset() faster?
{
findVertexIndex[i] = -1;
}
//Write vertex, normal and triangle infos in variables until maxVert is reached or end of TriangleList is reached
while (vertList.Count < maxVerts - 3 && positionTriangleList < completeMesh.TriangleList.Length)
{
for (int i = 0; i < 3; i++)
{
int indexCurrentVertex = completeMesh.TriangleList[positionTriangleList];
int newIndex = findVertexIndex[indexCurrentVertex];
if (newIndex == -1)
{
vertList.Add(completeMesh.VertexList[indexCurrentVertex]);
normList.Add(completeMesh.NormalList[indexCurrentVertex]);
findVertexIndex[indexCurrentVertex] = vertList.Count - 1;
triangles.Add(vertList.Count - 1);
}
else
{
triangles.Add(newIndex);
}
positionTriangleList++;
}
}
newMesh.VertexList = vertList.ToArray();
newMesh.NormalList = normList.ToArray();
newMesh.TriangleList = triangles.ToArray();
}
}
return(result);
}