public VertexTriangle GetFace(int index)
{
IndexTriangle t = _triangles[index];
FacePoint fp0 = _facePoints[t.Point0];
FacePoint fp1 = _facePoints[t.Point1];
FacePoint fp2 = _facePoints[t.Point2];
Vertex v0 = new Vertex(fp0, _buffers);
Vertex v1 = new Vertex(fp1, _buffers);
Vertex v2 = new Vertex(fp2, _buffers);
return(new VertexTriangle(v0, v1, v2));
}
public void GenerateBinormalTangentBuffers(int positionIndex, int uvIndex, bool addBinormals, bool addTangents)
{
IDataBuffer[] pBuffs = GetAllBuffersOfType(EBufferType.Position);
if (pBuffs.Length == 0)
{
Collada.WriteLine("No position buffers found.");
return;
}
if (!pBuffs.IndexInRange(positionIndex))
{
Collada.WriteLine("Position index out of range of available position buffers.");
return;
}
//IDataBuffer[] nBuffs = GetAllBuffersOfType(EBufferType.Normal);
//if (nBuffs.Length == 0)
//{
// Console.WriteLine("No normal buffers found.");
// return;
//}
//if (!nBuffs.IndexInRange(normalIndex))
//{
// Console.WriteLine("Normal index out of range of available normal buffers.");
// return;
//}
IDataBuffer[] tBuffs = GetAllBuffersOfType(EBufferType.TexCoord);
if (tBuffs.Length == 0)
{
Collada.WriteLine("No texcoord buffers found.");
return;
}
if (!tBuffs.IndexInRange(uvIndex))
{
Collada.WriteLine("UV index out of range of available texcoord buffers.");
return;
}
Vec3 pos1, pos2, pos3;
//Vec3 n0, n1, n2;
Vec2 uv1, uv2, uv3;
IDataBuffer pBuff = pBuffs[positionIndex];
//VertexBuffer nBuff = pBuffs[normalIndex];
IDataBuffer tBuff = tBuffs[uvIndex];
int pointCount = _triangles.Count * 3;
List <Vec3> binormals = new List <Vec3>(pointCount);
List <Vec3> tangents = new List <Vec3>(pointCount);
for (int i = 0; i < _triangles.Count; ++i)
{
IndexTriangle t = _triangles[i];
FacePoint fp0 = _facePoints[t.Point0];
FacePoint fp1 = _facePoints[t.Point1];
FacePoint fp2 = _facePoints[t.Point2];
pos1 = (Vec3)pBuff[fp0.BufferIndices[pBuff.Index]];
pos2 = (Vec3)pBuff[fp1.BufferIndices[pBuff.Index]];
pos3 = (Vec3)pBuff[fp2.BufferIndices[pBuff.Index]];
uv1 = (Vec2)tBuff[fp0.BufferIndices[tBuff.Index]];
uv2 = (Vec2)tBuff[fp1.BufferIndices[tBuff.Index]];
uv3 = (Vec2)tBuff[fp2.BufferIndices[tBuff.Index]];
Vec3 deltaPos1 = pos2 - pos1;
Vec3 deltaPos2 = pos3 - pos1;
Vec2 deltaUV1 = uv2 - uv1;
Vec2 deltaUV2 = uv3 - uv1;
Vec3 tangent;
Vec3 binormal;
float m = deltaUV1.X * deltaUV2.Y - deltaUV1.Y * deltaUV2.X;
if (m == 0.0f)
{
tangent = Vec3.UnitY;
binormal = Vec3.UnitY;
}
else
{
float r = 1.0f / m;
tangent = (deltaPos1 * deltaUV2.Y - deltaPos2 * deltaUV1.Y) * r;
binormal = (deltaPos2 * deltaUV1.X - deltaPos1 * deltaUV2.X) * r;
}
binormals.Add(binormal);
binormals.Add(binormal);
binormals.Add(binormal);
tangents.Add(tangent);
tangents.Add(tangent);
tangents.Add(tangent);
}
AddBuffer(binormals, EBufferType.Binormal);
AddBuffer(tangents, EBufferType.Tangent);
_bufferInfo.HasBinormals = true;
_bufferInfo.HasTangents = true;
}