[Mesa-dev] Handling component layouts in TGSI

[Marek Olšák]

Your proposition seems reasonable, but it's sad that drivers have to
deal with this.

Marek

On Mon, Jul 25, 2016 at 12:32 AM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> I was working on the component layouts stuff required for
> ARB_enhanced_layouts, and ran into an issue with representing this in
> TGSI.
>
> Right now when we indirectly index into arrays, we include an ArrayID
> to indicate which array it is we're indexing into.
>
> However with component layouts, we might have an array that spans
> components 0..2 of positions 0..10, and then another array that spans
> component 3 of positions 0..5 and another for component 3 of positions
> 6..10.
>
> I'm thinking that this will make sense to be represented as
>
> DECL IN[0..10](1).xyz
> DECL IN[0..5](2).w
> DECL IN[6..10](3).w
>
> And then accessing something like IN[4].xyzw would be fully legit,
> however indirect accesses would have to specify the array id, and only
> refer to the components of the declared array.
>
> Does this sound reasonable to everyone? Is there a better (read:
> simpler) way of handling this?
>
> Cheers,
>
>   -ilia
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/mesa-dev