[PATCH] wined3d: Implement icb dcl support in GLSL.

[Henri Verbeet]

On 13 June 2016 at 20:32, Józef Kucia <joseph.kucia at gmail.com> wrote:
> This implementation has some issues, e.g. a generated GLSL shader will
> produce a compilation error when the immediate constant buffer
> contains an unsigned integer which represents NaN. Morever, from
> testing a similar implementation, it seems that some drivers don't
> handle shaders with huge arrays very well and such shaders perform
> poorly. My current impression is that we should implement immediate
> constant buffers using a uniform variable.
>
Which drivers are that? Using uniforms does have some advantages, but
it also means the GLSL compiler potentially has less opportunities for
optimisation. Perhaps that's ok if we can safely assume any such
optimisations would have already been done by the HLSL compiler.
There's also the consideration that accessing uniforms can potentially
have higher latency than accessing immediate values, although I'm not
aware of any hardware that supports arrays of immediate values, as
opposed to single (vec4) values.