/// <summary>
/// Repacks all of the spherical harmonics coefficients used by probes to be used in shaders
/// </summary>
/// <param name="rawCoefficients">The input spherical harmonic coefficients</param>
/// <returns>The repacked coefficients, ready to be used in shaders</returns>
public static SphericalHarmonicsCoefficients RepackForShaders(this SphericalHarmonicsL2 rawCoefficients)
{
// https://docs.unity3d.com/Manual/LightProbes-TechnicalInformation.html -> http://www.ppsloan.org/publications/StupidSH36.pdf -> Appendix A10 : "Shader/CPU code for Irradiance Environment Maps"
SphericalHarmonicsCoefficients repackedCoefficients = new SphericalHarmonicsCoefficients();
repackedCoefficients.firstBandCoefficients = rawCoefficients.RepackFirstBandForShaders();
repackedCoefficients.shBr.x = rawCoefficients[0, 4];
repackedCoefficients.shBr.y = rawCoefficients[0, 5];
repackedCoefficients.shBr.z = rawCoefficients[0, 6] * 3.0f;
repackedCoefficients.shBr.w = rawCoefficients[0, 7];
repackedCoefficients.shBg.x = rawCoefficients[1, 4];
repackedCoefficients.shBg.y = rawCoefficients[1, 5];
repackedCoefficients.shBg.z = rawCoefficients[1, 6] * 3.0f;
repackedCoefficients.shBg.w = rawCoefficients[1, 7];
repackedCoefficients.shBb.x = rawCoefficients[2, 4];
repackedCoefficients.shBb.y = rawCoefficients[2, 5];
repackedCoefficients.shBb.z = rawCoefficients[2, 6] * 3.0f;
repackedCoefficients.shBb.w = rawCoefficients[2, 7];
repackedCoefficients.shC.x = rawCoefficients[0, 8];
repackedCoefficients.shC.y = rawCoefficients[1, 8];
repackedCoefficients.shC.z = rawCoefficients[2, 8];
repackedCoefficients.shC.w = 1.0f;
return(repackedCoefficients);
}
/// <summary>
/// Updates the spherical harmonics coefficients
/// </summary>
public void Update()
{
_coefficients = RenderSettings.ambientProbe.RepackForShaders();
}