OpenGL 3.3 and less hate for Open Source drivers

[BielBdeLuna]

there are two extensions that are not from the core profile, but the engine seems to not use them (maybe are from the old idTech4 engine in Doom3 times) those two:

• GL_ARB_texture_compression (for the s3tc compression, that doom3 used but maybe d3BFG doesn't use any-more (?) )
• GL_ARB_vertex_buffer_object

the code doesn't seem to use those extensions any further than checking for their existence

[kortemik]

@DanielGibson comments?

[BielBdeLuna]

r_useOpenGL32 no longer exists now. r_selectOpenGL is the same but it adds OpenGL 3.3 core profile

[BielBdeLuna]

confirmed: s3tc compression used in vanilla doom3 in image_load.cpp but no longer in use in ID's doom3-BFG:

https://github.com/TTimo/doom3.gpl/blob/master/neo/renderer/Image_load.cpp#L276

as well as the usage of VertexBufferObjectAvailable in that case named ARBVertexBufferObjectAvailable in draw_r200.cpp (that's for OpenGL 1.3 limited Ati Radeon r200, this stuff is old! it can't play the BFG version of the engine) obiously no longer present in OpenTech nor doom3BFG:

https://github.com/TTimo/doom3.gpl/blob/master/neo/renderer/draw_r200.cpp#L485

so both checks aren't used but make the code fail unneedlessly!

[BielBdeLuna]

now it really works! I had a very stupid but important error in the code added by me, in which I forced it to run at OpenGL 3.x even if r_selectOpenGL had a higher value, and so while it used OpenGL 3.3 it never compiled the CG to anything further than GLSL ES. Now instead, it compiles the CG to both GLSL 1.5 and 3.3 following whatever r_selectOpenGL states. so now it works as it should! :)

[BielBdeLuna]

a more important change have happened since then, I'll be back with a future pull request!