Will my modified ACES Tonemap work the same as the original one?
Yeah… right… I know I can just look for the differences on my own… "How I wish?" sorry but can't do.
As an amateur, I can't tell the differences with the original ACES and the ACES that I've modified (more like the short version of it).
vec3 tMACES(vec3 sample) {
sample = mat3(0.59719, 0.076, 0.0284, 0.35458, 0.90834, 0.13383, 0.04823, 0.01566, 0.83777) * sample;
sample = (sample * (sample + 0.0245786) - 0.000090537) / (sample * (0.983729 * sample + 0.432951) + 0.238081);
return mat3(1.60475, -0.10208, -0.00327, -0.53108, 1.10813, -0.07276, -0.07367, -0.00605, 1.07602) * sample;
}
Wondering what the original looks like?
// source: https://github.com/selfshadow/ltc_code/blob/master/webgl/shaders/ltc/ltc_blit.fs
vec3 RRTAndODTFit( vec3 v ) {
vec3 a = v * ( v + 0.0245786 ) - 0.000090537;
vec3 b = v * ( 0.983729 * v + 0.4329510 ) + 0.238081;
return a / b;
}
// this implementation of ACES is modified to accommodate a brighter viewing environment.
// the scale factor of 1/0.6 is subjective. see discussion in #19621.
vec3 ACESFilmicToneMapping( vec3 color ) {
// sRGB => XYZ => D65_2_D60 => AP1 => RRT_SAT
const mat3 ACESInputMat = mat3(
vec3( 0.59719, 0.07600, 0.02840 ), // transposed from source
vec3( 0.35458, 0.90834, 0.13383 ),
vec3( 0.04823, 0.01566, 0.83777 )
);
// ODT_SAT => XYZ => D60_2_D65 => sRGB
const mat3 ACESOutputMat = mat3(
vec3( 1.60475, -0.10208, -0.00327 ), // transposed from source
vec3( -0.53108, 1.10813, -0.07276 ),
vec3( -0.07367, -0.00605, 1.07602 )
);
color *= toneMappingExposure / 0.6;
color = ACESInputMat * color;
// Apply RRT and ODT
color = RRTAndODTFit( color );
color = ACESOutputMat * color;
// Clamp to [0, 1]
return saturate( color );
}
Don't trust the code above? Click here then.
Helpful tips is much appreciated.
