Basic for/while loops work now.
Only one level of loop nesting is supported at this time (same for if/else).
The progs/glsl/mandelbrot demo works, but the colors are too dim.
Now only the samplers that are actually used by texture() functions are
saved in the uniform variable list. Before, we could run out of samplers
if too many were declared while only some of them were actually used.
The max texture coord units is still 8. All the fixed-function paths are
still limited to 8 too. But GLSL shaders can use more samplers now.
Note that some texcoord-related data structures are declared to be 16
elements in size rather than 8. This just simplifies the code in a few
places; the extra elements aren't accessible to the user.
These changes haven't been extensively tested yet, but sanity checking has
been done.
It should be possible to increase the max image units/samplers to 32 without
doing anything special. Beyond that we'll need longer bitfields in a few
places.
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.
