/// <summary>
/// Generate a spherical harmonic from the faces of a cubemap, treating each pixel as a light source and averaging the result.
/// </summary>
public static SphericalHarmonicL2RGB GenerateSphericalHarmonicFromCubeMap(
Vector3[] colourDataPositiveX,
Vector3[] colourDataNegativeX,
Vector3[] colourDataPositiveY,
Vector3[] colourDataNegativeY,
Vector3[] colourDataPositiveZ,
Vector3[] colourDataNegativeZ)
{
if (colourDataPositiveX == null ||
colourDataNegativeX == null ||
colourDataPositiveY == null ||
colourDataNegativeY == null ||
colourDataPositiveZ == null ||
colourDataNegativeZ == null)
{
throw new ArgumentNullException();
}
SphericalHarmonicL2RGB sh = new SphericalHarmonicL2RGB();
Vector3[][] source =
{
colourDataPositiveX,
colourDataNegativeX,
colourDataPositiveY,
colourDataNegativeY,
colourDataPositiveZ,
colourDataNegativeZ,
};
//extract the 6 faces of the cubemap.
for (int face = 0; face < 6; face++)
{
int size = (int)(Math.Sqrt(source[face].Length) + 0.5);
if (size * size != source[face].Length)
{
throw new ArgumentException("Cubemap face is an unexpected (non square) size");
}
Microsoft.Xna.Framework.Graphics.CubeMapFace faceId = (Microsoft.Xna.Framework.Graphics.CubeMapFace)face;
//get the transformation for this face,
Matrix cubeFaceMatrix;
Xen.Graphics.DrawTargetTextureCube.GetCubeMapFaceMatrix(faceId, out cubeFaceMatrix);
//extract the spherical harmonic for this face and accumulate it.
sh += ExtractSphericalHarmonicForCubeFace(cubeFaceMatrix, source[face], size);
}
//average out over the sphere
return(sh.GetWeightedAverageLightInputFromSphere());
}
/// <summary>
/// Generate a spherical harmonic from the faces of a cubemap, treating each pixel as a light source and averaging the result.
/// </summary>
public static SphericalHarmonicL2RGB GenerateSphericalHarmonicFromCubeMap(
Vector3[] colourDataPositiveX,
Vector3[] colourDataNegativeX,
Vector3[] colourDataPositiveY,
Vector3[] colourDataNegativeY,
Vector3[] colourDataPositiveZ,
Vector3[] colourDataNegativeZ)
{
if (colourDataPositiveX == null ||
colourDataNegativeX == null ||
colourDataPositiveY == null ||
colourDataNegativeY == null ||
colourDataPositiveZ == null ||
colourDataNegativeZ == null)
throw new ArgumentNullException();
SphericalHarmonicL2RGB sh = new SphericalHarmonicL2RGB();
Vector3[][] source = {
colourDataPositiveX,
colourDataNegativeX,
colourDataPositiveY,
colourDataNegativeY,
colourDataPositiveZ,
colourDataNegativeZ,
};
//extract the 6 faces of the cubemap.
for (int face = 0; face < 6; face++)
{
int size = (int)(Math.Sqrt(source[face].Length) + 0.5);
if (size * size != source[face].Length)
throw new ArgumentException("Cubemap face is an unexpected (non square) size");
Microsoft.Xna.Framework.Graphics.CubeMapFace faceId = (Microsoft.Xna.Framework.Graphics.CubeMapFace)face;
//get the transformation for this face,
Matrix cubeFaceMatrix;
Xen.Graphics.DrawTargetTextureCube.GetCubeMapFaceMatrix(faceId, out cubeFaceMatrix);
//extract the spherical harmonic for this face and accumulate it.
sh += ExtractSphericalHarmonicForCubeFace(cubeFaceMatrix, source[face], size);
}
//average out over the sphere
return sh.GetWeightedAverageLightInputFromSphere();
}
