/*-----------------------------------------------------------------------------------------
*
* Computational and optimization stuff :
*
* -----------------------------------------------------------------------------------------*/
/// <summary>
/// Defragmentates mesh subsets with same materials
/// </summary>
public void DefragmentSubsets(Scene scene, bool takeFromTriangleMtrlIndices)
{
// if there are not shading groups,
// take them from per triangle material indices
if (!Subsets.Any() || takeFromTriangleMtrlIndices)
{
for (int i = 0; i < Triangles.Count; i++)
{
MeshSubset sg = new MeshSubset();
sg.MaterialIndex = Triangles[i].MaterialIndex;
sg.StartPrimitive = i;
sg.PrimitiveCount = 1;
Subsets.Add(sg);
//Console.Write( "*{0}", Triangles[i].MaterialIndex );
}
}
if (Subsets.Count == 1)
{
return;
}
List <List <MeshTriangle> > perMtrlTris = new List <List <MeshTriangle> >();
foreach (var mtrl in scene.Materials)
{
perMtrlTris.Add(new List <MeshTriangle>());
}
foreach (var sg in Subsets)
{
for (int i = sg.StartPrimitive; i < sg.StartPrimitive + sg.PrimitiveCount; i++)
{
perMtrlTris[sg.MaterialIndex].Add(Triangles[i]);
}
}
Subsets.Clear();
Triangles.Clear();
for (int i = 0; i < perMtrlTris.Count; i++)
{
var sg = new MeshSubset();
sg.MaterialIndex = i;
sg.StartPrimitive = Triangles.Count;
sg.PrimitiveCount = perMtrlTris[i].Count;
if (sg.PrimitiveCount == 0)
{
continue;
}
Triangles.AddRange(perMtrlTris[i]);
Subsets.Add(sg);
}
}