Basic Tonemapper

[TheIronLefty]

Hello,

I recently saw that you commited a very basic tonemapper that is based on Filmic from 2010 blogpost, I wanted to ask why not consider simple ACES or AgX?

I do understand that MJP's refitting ACES implementation is bit big and not really (simplistic), but I do I have a custom ACES curve that i can PR if this is fine :).

[zeux]

I actually tried a few ACES and AgX variants initially but ended up going back to tried and true filmic for now, as I preferred the look and simplicity.

[zeux]

And yeah I tried the ACES code by Stephen Hill as well, it was part of this set: https://github.com/mrdoob/three.js/blob/dev/src/renderers/shaders/ShaderChunk/tonemapping_pars_fragment.glsl.js. I also tried Khronos's PBR Neutral operator, which I liked the least; I think the next best option I liked after filmic operator was AgX (with no look component), but it was much more complex and wasn't obviously better on the current scene & shading setup. This could be revisited in the future of course!

[TheIronLefty]

This is the custom ACES curve tonemapper i was talking about, it's by my friend Marlon, you can try it out and see if it fits to your liking.

float3 nautilus(float3 c)
{
    // Nautilus fit of ACES
    // By Nolram
    
    float a = 2.51f;
    float b = 0.03f;
    float y = 2.43f;
    float d = 0.59f;
    float e = 0.14f;
    return clamp((c * (a * c + b)) / (c * (y * c + d) + e), 0.0, 1.0);
}