srgb_gamma.glsl

// sRGB to/from linear-space conversions, by Ian Taylor
// source: http://chilliant.blogspot.be/2012/08/srgb-approximations-for-hlsl.html

// Alternate LinearToGamma(), without pow():
// srgb = 0.585122381 * sqrt(linear) +
//        0.783140355 * sqrt(sqrt(linear)) -
//        0.368262736 * sqrt(sqrt(sqrt(linear)));

vec3 LinearToGamma(in vec3 linear) {
	return max(1.055f * pow3(linear, 0.416666667f) - 0.055f, 0);
}

vec3 GammaToLinear(in vec3 sRGB) {
	return 0.012522878f * sRGB +
	       0.682171111f * sRGB * sRGB +
	       0.305306011f * sRGB * sRGB * sRGB;
}

float LinearToGammaF(in float linear) {
	return max(1.055f * pow(linear, 0.416666667f) - 0.055f, 0);
}

float GammaToLinearF(in float sRGB) {
	return 0.012522878f * sRGB +
	       0.682171111f * sRGB * sRGB +
	       0.305306011f * sRGB * sRGB * sRGB;
}