public static void ComputeTangent(ref VertexPNTTB srcVert, VertexPNTTB vert1, VertexPNTTB vert2)
{
Vector4 d0 = vert1.Position - srcVert.Position;
Vector4 d1 = vert2.Position - srcVert.Position;
Vector2 s = vert1.Texcoord - srcVert.Texcoord;
Vector2 t = vert2.Texcoord - srcVert.Texcoord;
float r = 1.0F / (t.X * s.Y - t.Y * s.X);
Vector3 tangent = new Vector3(s.Y * d1.X - t.Y * d0.X, s.Y * d1.Y - t.Y * d0.Y, s.Y * d1.Z - t.Y * d0.Z) * r;
srcVert.Tangent = Vector3.Normalize(tangent - srcVert.Normal * Vector3.Dot(srcVert.Normal, tangent));
}
void ParseSMDTriangles(StreamReader file)
{
if (this.modelGroups != null)
return;
SortedList<string, List<VertexPNTTB>> vertexLists = new SortedList<string, List<VertexPNTTB>>();
SortedList<string, List<ushort>> indicesList = new SortedList<string, List<ushort>>();
while (!file.EndOfStream)
{
string text = file.ReadLine();
if (text == "end")
{
break;
}
string materialName = text.Split('.')[0];
if (!vertexLists.ContainsKey(materialName))
{
vertexLists.Add(materialName, new List<VertexPNTTB>());
indicesList.Add(materialName, new List<ushort>());
}
VertexPNTTB[] vertices = new VertexPNTTB[3];
for (int i = 0; i < 3; i++)
{
text = file.ReadLine();
string[] data = text.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
Vector4 bone = new Vector4(int.Parse(data[0]), 0, 0, 0);
Vector4 boneWeights = new Vector4(1.0f, 0, 0, 0);
Vector3 pos;
pos.X = float.Parse(data[1]);
pos.Y = float.Parse(data[2]);
pos.Z = float.Parse(data[3]);
Vector3 normal;
normal.X = float.Parse(data[4]);
normal.Y = float.Parse(data[5]);
normal.Z = float.Parse(data[6]);
normal.Normalize();
Vector2 texcoord;
texcoord.X = float.Parse(data[7]);
texcoord.Y = float.Parse(data[8]);
if (data.Length > 10) //Code for multiple blendweights
{
int boneBlendCount = int.Parse(data[9]);
for (int m = 0; m < boneBlendCount; m++)
{
int index = m * 2 + 10;
switch (m)
{
case 0:
bone.Y = int.Parse(data[index]);
boneWeights.Y = float.Parse(data[index + 1]);
break;
case 1:
bone.Z = int.Parse(data[index]);
boneWeights.Z = float.Parse(data[index + 1]);
break;
case 2:
bone.W = int.Parse(data[index]);
boneWeights.W = float.Parse(data[index + 1]);
break;
}
}
float sum = Vector4.Dot(boneWeights, Vector4.One);
boneWeights.X = 1.0f - sum;
}
vertices[i] = new VertexPNTTB(pos, normal, texcoord, bone, boneWeights, Vector3.Zero);
indicesList[materialName].Add((ushort)(vertexLists[materialName].Count+i));
}
//Compute our tangent vectors
MathUtils.ComputeTangent(ref vertices[0], vertices[1], vertices[2]);
MathUtils.ComputeTangent(ref vertices[1], vertices[2], vertices[0]);
MathUtils.ComputeTangent(ref vertices[2], vertices[0], vertices[1]);
vertexLists[materialName].AddRange(vertices);
}
this.modelGroups = new ModelPart[vertexLists.Keys.Count];
for (int i = 0; i < vertexLists.Keys.Count; i++)
{
string key = vertexLists.Keys[i];
VertexBuffer vertexBuffer = new VertexBuffer(GFX.Device, vertexLists[key].Count * VertexPNTTB.SizeInBytes, BufferUsage.WriteOnly);
vertexBuffer.SetData<VertexPNTTB>(vertexLists[key].ToArray());
IndexBuffer indexBuffer = new IndexBuffer(GFX.Device, sizeof(ushort) * indicesList[key].Count, BufferUsage.WriteOnly, IndexElementSize.SixteenBits);
indexBuffer.SetData<ushort>(indicesList[key].ToArray());
Vector3 pos = new Vector3(vertexLists[key][0].Position.X, vertexLists[key][0].Position.Y, vertexLists[key][0].Position.Z);
BoundingBox bounds = new BoundingBox(pos, pos);
for (int j = 0; j < vertexLists[key].Count; j++)
{
pos = new Vector3(vertexLists[key][j].Position.X, vertexLists[key][j].Position.Y, vertexLists[key][j].Position.Z);
bounds.Max = Vector3.Max(bounds.Max, pos);
bounds.Min = Vector3.Min(bounds.Min, pos);
}
modelGroups[i] = new ModelPart(key, vertexBuffer, indexBuffer, bounds);
}
}