ATIs.
This is actually a test to see if this can be enabled on ATI cards.
According to various sources, newer ATI cards supporting GLSL 3.0
support gl_ClippingDistance in shaders, which is the forward compatible
way to do custom clipping.
This fix will bind 6 additional varying variables on ATIs, which may
lead to some shaders not compiling due to limiting out of those
variables, or to performance degradation. Also I do not have an ATI
handy to test.
Having those in mind, this commit may well be reverted later.
Clipping planes are usually 4 (6 is for cube clipping), but making
shaders depend on viewport state is really bad, and would lead to
recompilation, so I took the worst case here to avoid that.
Hopefully driver does some optimization there.
Clipping border causes a software fallback on ATIs. We have disabled it
in that case but from minor digging on the net seems like Intels support
this, so enable.
code is still unused, but the intention is to use this to solve the double sided
lighting problem on NVidia, and to make the materials work on OpenGL ES 2.0
eventually.
The code works and matches the fixed function lighting pretty much exactly, but
still needs optimizations. The actual integration in object draw will be
committed later when more fixing & testing, there's lots of different combinations
and unclear OpenGL state here.
* Shadow color now usable in the BGE
* Simplified the shadow panel while "Blender Game" renderer is active
* Added variance shadow maps for the BGE
* Buffered shadows on sun lamps in the BGE (orthographic)
* Light textures in the BGE
