[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [50282] trunk/blender/source/blender: Fix #32404: GLSL normal maps using float images were incorrectly getting

[Antony Riakiotakis]

Hi brecht, this commit most likely causes this bug when texture
painting http://blenderartists.org/forum/showthread.php?269851-Texture-Paint-Layer-Manager-add-on-Bump-problem.

The issue happens because when texture painting we always colour
correct float images. There are a few ways to solve this:

- Get the information about colour correcting or not in texture paint
as well (during stroke operator initialization). This requires looking
up the active object's material and texture slots. It can be done
though the issue might get complicated if the image is shared,
assigned to colour in another material. Which version of the GPU
texture (colour corrected or not) will be used then?

- Always upload in sRGB space and do the reverse conversion in bump
shading code. This will eat away some performance but it's the most
"exact" solution IMO.

- Never colour correct images and UI elements and use sRGB
framebuffers in openGL :p. This has the drawback of not being able to
customize the display space and relying too much on graphics driver
correctness. But there are times (like this) where it just keeps
popping into my mind :)