/// <summary>
///
/// </summary>
/// <param name="v0"></param>
/// <param name="v1"></param>
/// <returns></returns>
int ClassifyVertexPair(MeshVertex v0, MeshVertex v1)
{
int res = 0;
if (v0.Position.X < v1.Position.X)
{
res |= 0x1;
}
if (v0.Position.Y < v1.Position.Y)
{
res |= 0x2;
}
if (v0.Position.Z < v1.Position.Z)
{
res |= 0x4;
}
return(res);
}
/// <summary>
/// Inserts node to oct tree
/// </summary>
int InsertVertex(ref OctNode node, MeshVertex v, float tolerance)
{
if (node == null)
{
node = new OctNode(); node.index = Vertices.Count;
Vertices.Add(v);
return(node.index);
}
if (CompareVertexPair(Vertices[node.index], v, tolerance))
{
return(node.index);
}
int r = ClassifyVertexPair(Vertices[node.index], v);
return(InsertVertex(ref node.nodes[r], v, tolerance * tolerance));
}
/// <summary>
/// Merges vertices
/// </summary>
public void MergeVertices(float tolerance)
{
OctNode root = null;
List <MeshVertex> oldVertices = new List <MeshVertex>(Vertices);
Vertices.Clear();
for (int i = 0; i < Triangles.Count; i++)
{
MeshVertex v0 = oldVertices[Triangles[i].Index0];
MeshVertex v1 = oldVertices[Triangles[i].Index1];
MeshVertex v2 = oldVertices[Triangles[i].Index2];
int i0 = InsertVertex(ref root, v0, tolerance);
int i1 = InsertVertex(ref root, v1, tolerance);
int i2 = InsertVertex(ref root, v2, tolerance);
int mtrl = Triangles[i].MaterialIndex;
Triangles[i] = new MeshTriangle(i0, i1, i2, mtrl);
}
}
/*-----------------------------------------------------------------------------------------
*
* Tangent space :
*
* -----------------------------------------------------------------------------------------*/
/// <summary>
/// Computes tangent frame
/// </summary>
public void ComputeTangentFrame()
{
for (int i = 0; i < TriangleCount; i++)
{
var tri = Triangles[i];
var inds = new[] { tri.Index0, tri.Index1, tri.Index2 };
for (uint j = 0; j < 3; j++)
{
MeshVertex vert0 = Vertices[inds[(0 + j) % 3]];
MeshVertex vert1 = Vertices[inds[(1 + j) % 3]];
MeshVertex vert2 = Vertices[inds[(2 + j) % 3]];
Vector3 v0 = vert1.Position - vert0.Position;
Vector3 v1 = vert2.Position - vert0.Position;
Vector2 t0 = vert1.TexCoord0 - vert0.TexCoord0;
Vector2 t1 = vert2.TexCoord0 - vert0.TexCoord0;
{ // X :
float det = t0.X * t1.Y - t1.X * t0.Y;
float dett = v0.X * t1.Y - v1.X * t0.Y;
float detb = t0.X * v1.X - t1.X * v0.X;
//if (Math.Abs(det)<float.Epsilon) Log.Warning("Tri is too small");
vert0.Tangent.X = dett / det;
vert0.Binormal.X = detb / det;
}
{ // Y :
float det = t0.X * t1.Y - t1.X * t0.Y;
float dett = v0.Y * t1.Y - v1.Y * t0.Y;
float detb = t0.X * v1.Y - t1.X * v0.Y;
//if (Math.Abs(det)<float.Epsilon) Log.Warning("Tri is too small");
vert0.Tangent.Y = dett / det;
vert0.Binormal.Y = detb / det;
}
{ // Z :
float det = t0.X * t1.Y - t1.X * t0.Y;
float dett = v0.Z * t1.Y - v1.Z * t0.Y;
float detb = t0.X * v1.Z - t1.X * v0.Z;
//if (Math.Abs(det)<float.Epsilon) Log.Warning("Tri is too small");
vert0.Tangent.Z = dett / det;
vert0.Binormal.Z = detb / det;
}
//vert0.Normal = Vector3.Cross(v1, v0);
if (vert0.Tangent.Length() > float.Epsilon * 8)
{
vert0.Tangent.Normalize();
}
if (vert0.Binormal.Length() > float.Epsilon * 8)
{
vert0.Binormal.Normalize();
}
if (vert0.Normal.Length() > float.Epsilon * 8)
{
vert0.Normal.Normalize();
}
//vert0.Tangent.Normalize() ;
//vert0.Binormal.Normalize() ;
//vert0.Normal.Normalize() ;
Vector3 temp;
temp = Vector3.Cross(vert0.Tangent, vert0.Normal);
vert0.Tangent = Vector3.Cross(vert0.Normal, temp);
temp = Vector3.Cross(vert0.Binormal, vert0.Normal);
vert0.Binormal = Vector3.Cross(vert0.Normal, temp); //*/
// assign vertex
Vertices[inds[(0 + j) % 3]] = vert0;
}
}
}
/// <summary> /// /// </summary> /// <param name="vertex"></param> /// <returns></returns> public abstract TVertex Convert(MeshVertex vertex);
