On Sat, 2012-04-28 at 13:02 -0700, Kenneth Graunke wrote: > On 04/28/2012 12:24 PM, Vadim Girlin wrote: > > On Sat, 2012-04-28 at 11:42 -0700, Kenneth Graunke wrote: > >> On 04/28/2012 11:20 AM, Vadim Girlin wrote: > >>> According to GLSL 1.30 specification, initial value for all uniforms > >>> without initializer is 0. Some applications rely on this behaviour, > >>> e.g. google's MapGL doesn't set all sampler uniforms. > >>> > >>> (see https://bugs.freedesktop.org/show_bug.cgi?id=49088 ) > >>> > >>> Signed-off-by: Vadim Girlin<vadimgir...@gmail.com> > >>> --- > >>> > >>> Tested with r600g only - no regressions. > >> > >> Awesome find! I was at a complete loss here. :) > >> > >> It turns out this is in the 1.20 spec too; it looks like 1.10 doesn't > >> say (but that isn't too surprising). I might add a comment: > >> > >> /* From the GLSL 1.20 specification, page 24, section 4.3.5 "Uniform": > >> * "The link time initial value is either the value of the variable's > >> * initializer, or 0 if no initializer present. Sampler types cannot > >> * have initializers." > >> */ > >> > >> Also, do you really need the memsets in ir_to_mesa and st_glsl_to_tgsi? > >> Everything should go through the linker, so that seems somewhat > >> redundant. I tested with just the link_uniforms change and that was > >> enough to fix MapsGL on i965/Sandybridge. > > > > Without the memset in the st_glsl_to_tgsi firefox crashed with MapGL. > > Probably some code in the state tracker relies on the synchronized > > values of the SamplerUnits arrays in the gl_program and > > gl_shader_program. Also, _mesa_uniform function compares these arrays to > > check for update, and some piglit test failed due to the following > > problem: > > > > First array is initialized: 0, 0, 0, ... > > Second (without memset) : 0, 1, 2, ... > > > > The app calls Uniform1i to set sampler[1] to 1, so we do first[1]=1, but > > then it's equal with second[1] and update is not detected. > > > > Vadim > > Ah, okay...I missed that one was operating on the gl_shader_program > while the other was setting the parallel structure in the gl_program. > > I can believe that you'd need that, then. >
BTW, it seems there is a patch from Ian for this issue on the list: http://lists.freedesktop.org/archives/mesa-dev/2012-April/020767.html Vadim _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
