public Matrix4f SetToLookAt(Vector3f dir, Vector3f up)
{
this.SetToIdentity();
l_vez.Set(dir);
l_vez.NormalizeStore();
l_vex.Set(dir);
l_vex.NormalizeStore();
l_vex.CrossStore(up);
l_vex.NormalizeStore();
l_vey.Set(l_vex);
l_vey.CrossStore(l_vez);
l_vey.NormalizeStore();
this.values[Matrix4f.m00] = l_vex.x;
this.values[Matrix4f.m01] = l_vex.y;
this.values[Matrix4f.m02] = l_vex.z;
this.values[Matrix4f.m10] = l_vey.x;
this.values[Matrix4f.m11] = l_vey.y;
this.values[Matrix4f.m12] = l_vey.z;
this.values[Matrix4f.m20] = l_vez.x;
this.values[Matrix4f.m21] = l_vez.y;
this.values[Matrix4f.m22] = l_vez.z;
return(this);
}
public static void CalculateTangents(List<Vertex> vertices, List<int> indices)
{
for (int i = 0; i < indices.Count; i += 3)
{
try
{
Vertex v0 = vertices[indices[i]];
Vertex v1 = vertices[indices[i + 1]];
Vertex v2 = vertices[indices[i + 2]];
Vector2f uv0 = v0.GetTexCoord0();
Vector2f uv1 = v1.GetTexCoord0();
Vector2f uv2 = v2.GetTexCoord0();
Vector3f edge1 = v1.GetPosition().Subtract(v0.GetPosition());
Vector3f edge2 = v2.GetPosition().Subtract(v0.GetPosition());
Vector2f edge1uv = uv1.Subtract(uv0);
Vector2f edge2uv = uv2.Subtract(uv0);
float cp = edge1uv.y * edge2uv.x - edge1uv.x * edge2uv.y;
if (cp != 0.0f)
{
float mul = 1.0f / cp;
Vector3f tangent = new Vector3f().Set(edge1.Multiply(-edge2uv.y).AddStore(edge2.Multiply(edge1uv.y)));
tangent.MultiplyStore(mul);
Vector3f bitangent = new Vector3f().Set(edge1.Multiply(-edge2uv.x).AddStore(edge2.Multiply(edge1uv.x)));
bitangent.MultiplyStore(mul);
tangent.NormalizeStore();
bitangent.NormalizeStore();
v0.SetTangent(tangent);
v1.SetTangent(tangent);
v2.SetTangent(tangent);
v0.SetBitangent(bitangent);
v1.SetBitangent(bitangent);
v2.SetBitangent(bitangent);
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
}
