Mostly accurate Palette Tonemapping

[Dark-Assassin]

Mostly accurate palette tonemapping for GZDoom.

Currently supports Doom, Heretic, Hexen, and Strife

Screenshots:

GZDoom with this mod:
https://raw.githubusercontent.com/AJMJ2012/XPaletteTonemap/main/screenshots/xtonemap.png

Original Doom:
https://raw.githubusercontent.com/AJMJ2012/XPaletteTonemap/main/screenshots/dos.png

GZDoom's inbuilt tonemap:
https://raw.githubusercontent.com/AJMJ2012/XPaletteTonemap/main/screenshots/gzpalette.png

• GZDoom rendering at 320x200 and lighting mode "Software"

Github: https://github.com/AJMJ2012/XPaletteTonemap

Edit: For those who would want to see what it looks like with the "Vanilla" light mode.
https://cdn.discordapp.com/attachments/401474936188829706/849477203318014032/Screenshot_Doom_20210602_120849.png

[Caligari87]

I know we talked about it on Discord, but I'm insanely curious why palette tonemapping with "Software" lightmode looks closer to DOS Doom, when it's been accepted for years that this lighting mode was inferior and inaccurate. The "Vanilla" lightmode most definitely looks too dark even though it's supposedly more mathematically accurate to the original.

Perhaps that's why Randi brightened the "Software" light mode, because ZDoom didn't have true-color at the time and the actual formula ends up darker for some reason?

[Dark-Assassin]

Added dithering.