Add scalable linear light texture for shaders

Certain scaling filters are designed to operate in non-gamma (i.e. linear) color space. Manually trying to calculate linear light in shader code interferes with mpv's color conversions and might break things. I want to be able to request a scalable linear texture from mpv, process it, and give it back to mpv for necessary color conversions.

Alternatively, if you can suggest me a proper shader code that won't break things, I could use that. I tried implementing mpv's sRGB to linear and vice-versa conversions in shader code, and it mostly worked fine, but I have encountered some cases where it causes artifacts. If I hook and process MAIN with the code below, I get artifacts. I don't understand much of the color theory, but I presume it is because MAIN is not sRGB but RGB. Is that correct?

vec3 srgb_to_linear(vec3 col) {
	return mix(col * 1.0 / 12.92,  pow((col + 0.055) / 1.055, vec3(2.4)), ivec3(lessThan(vec3(0.04045), col)));
}

vec3 linear_to_srgb(vec3 col) {
	return mix(col * 12.92, 1.055 * pow(col, vec3(1.0 / 2.4)) - 0.055, ivec3(lessThanEqual(vec3(0.0031308), col)));
}

No file, test, or entry point is named. Start by tracing mpv's shader and color-conversion handling, then determine how a scalable linear texture could cross that pipeline without introducing artifacts. Done would require an agreed design and either the requested texture support or a validated shader-based alternative.