improved tone mapping (uncharted tonemapper)

[Thomason1005]

i only recently came across the issues of linear tonemapping and noticed og suffers the same problems, as it oversaturates bright colors.

i roughly implemented the uncharted tonemapper described here:https://www.slideshare.net/ozlael/hable ... r-lighting

it isnt exactly as described (why would i expose after tonemapping?) but i think it removes the issue