This lets us avoid software fallbacks when clients forget to turn some state
off (engine demo) or just do crazy things to test conformance (OGLC).
This should probably be brought into mesa generic code so other drivers can
make use of it.
Bug #19016.
This allows code such as "vec4 a = gl_LightSource[i].ambient;" to work.
When a built-in uniform array is indexed with a variable index we need to
"unroll" the whole array into the parameter list (aka constant buffer) because
we don't know which elements may be accessed at compile-time. In the case of
the gl_LightSource array of size [8], we emit 64 state references into the
parameter array (8 elements times 8 vec4s per gl_LightSourceParameters
struct).
Previously, we only allowed constant-indexed references to uniform arrays
(such as gl_LightSource[2].position) which resulted in a single state reference
being added to the parameter array, not 64. We still optimize this case.
Users should be aware that using "gl_LightSource[i].ambient" in their shaders
is a bit expensive since state validation will involve updating all 64
light source entries in the parameter list.
MSVC may not support full C99, but supports more than plain C90. And
-pedantic without -std=c99 generates too many spurious warnings
(specially C++ style comments) to be of any use.
Note that using certain C99 features in the cross-platform parts of Gallium
is still not possible; namely mid-of-scope variable declarations and named
structure initializers will break MSVC builds.
We'd come up with a negative remainder, while we were looking for the positive
version of it in the loop conditional. And, since the "did we hit our target"
break was disabled for the target_msc == 0 ("Just make the divisor/remainder
work") path, we'd never exit.
Simplify the code by just using int64_t all over instead of trying to do it
in a u32 space.
Previously fog parameter and specular color are packed into the
same dword. Note specular color should be packed in BGRA for device,
so if fog parameter and specular color all are present, fog parameter
will dirty the alpha term of specular color. This fixes rendering
issue when playing 'Yo Frankie' on 915/945.