[waffle] Waffle and GL dispatch

[Chad Versace]

On Thu, Jun 26, 2014 at 05:46:56PM +0100, Eric Anholt wrote:
> Emil Velikov <emil.l.velikov at gmail.com> writes:
> > Not aiming at it atm, but just curious - which one would you consider as the
> > better option:
> >  - Convert waffle to use libepoxy, or
> >  - clone the current implementation into waffle and work from there ?
> 
> Make waffle link against libepoxy.

I don't want to import the libepoxy code into waffle. But I'm also not
fundamentally opposed to adding a written-from-scratch dispatch
mechanism to waffle. But, we should avoid adding any
written-from-scratch dispatch until (1) waffle's users (piglit,
apitrace, maybe a few more?) really need dispatch and (2) we've made
a real effort to make libepoxy work.

(There does exist a waffle user, Piglit, who *does* need dispatch, and
libepoxy today doesn't work for it, and I just recently rewrote large
hunks of Piglit's homebrew dispatch, but I digress... I'm still waiting
for libepoxy to become Piglit-friendly).

As for why Eric didn't add dispatch to waffle, it's because most users
just want dispatch and not the GLX/CGL/Android/EGL abstraction that
waffle provides. Any realworld app, like a game, needs much more from a
platform abstraction layer than what waffle provides and will ever
provide, such as input and audio. Since realworld games already have
chosen their own platform abstraction layer, it doesn't make sense to
require them to add another platform abstraction (waffle) to be able to
get sane GL dispatch.