This is a slighty revised version of id Software original code. Icculus
code may have some advantages on broken drivers or underpowered GPUs.
Today it's just a performance hook. This is a first step in fixing #147.
This is based on work submitted by Scott "pickle" Smith. It's said that
vertex arrays are somewhat faster and more compatible than the old way.
This may remove support of some very, very old GPUs like the Riva128.
This is based upon the original OpenGL ES patch by Scott "pickle"
Smith. This change gives about the same frame rate on an 750TI but
about 3% more frames on an Ivy Bridge IGP with Mesa3D...
Multitexturing was enabled by default in 0f7b422. It gives a small but
on todays hardware neglectable performance boost, but caused several
problems over the years. For example gl_showtris doesn't work with it
and there's at least one render glitch in city3.bsp.
Retexturing support is now always on (you can still switch it off with
the gl_retexturing CVAR), as we don't have the additional libjpeg
dependency anymore.
stb_image is used for tga, jpg and the newly supported png, so the
old tga and jpeg loading code has been removed.
I furthermore cleaned up the somehow messy and possibly slightly broken
retexturing selection code in R_FindImage()
Check and use GL_ARB_texture_non_power_of_two and use it if present to allow using all textures unscaled. This makes a huge visual improvement since most skins are not power-of-two textures.
Conflicts:
src/client/refresh/header/local.h
MSAA was a long wanted and often requested feature. Just set set the
desired number of samples with gl_msaa_samples and do a vid_restart.
This code is based upon work done in Hecatomb.
Those extensions have become part of ARB about 15 years ago and most if
not all video cards still in use should support the ARB versions. I
believe that at least parts of this code were disfunctional.
This removes the need to define the old qgl function names to the
official OpenGL names. The OpenGL functions are now called directly
without any abstraction.
