I decided to make a quick eye adaption filter using my knowledge of how it works. It turned out to work very well. It is using the latest UPBGE features which include full HDR(to prevent color banding) aswell as mipmaps for efficient average brightness detection.
In case if you see big exprossure diferences at diferent parts of screen, you may increase the mip map level and hope that it won’t mess it up at lower resolutions. Feel free to play around with it:)
DOWNLOAD: http://pasteall.org/blend/index.php?id=45926
BLENDERARTISTS.ORG THREAD (with up to date downloads and shader code): https://blenderartists.org/forum/showthread.php?418056-UPBGE-HDR-Eye-Adaption-Filter
Textures from textures.com
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