Upcoming Qt switch to OpenGL ES on arm64

[bret curtis]

Hi!

On Mon, Nov 26, 2018 at 11:40 AM Raphael Hertzog <hertzog at debian.org> wrote:
> >
> > What applications does Debian have in its repo that only support GLES?
>
> Wrong question. Maybe it makes sense for you at the application level for
> the application that are hooking into OpenGL directly. But we are speaking
> of having decent graphical performances for all Qt based-applications on
> hardware that only support GLES and not Desktop OpenGL.
>

This is the wrong assumption because if your hardware supports GLES,
then it also supports GL. It is only the proprietary
module/driver/firmware that exposes the GLES only. Take a look at all
the mesa drivers, they all support OpenGL and GLES.

> That kind of hardware does exist now and people who try to use Debian
> on it will be disappointed because even LXQt will feel sluggish on them.
>

The hardware that supports GLES also supports OpenGL because GLES is a
subset of OpenGL. I find it very hard to believe that the hardware
somehow performs differently, if anything, the difference probably
comes from the proprietary module/driver/firmware.

> This is not a easy decision to make, in the ideal world we would support
> both Qt stack but this is not realistic and we have to make a choice.
>

It is not an easy decision to make. I grant you that.

>
> In my opinion, Debian as a universal operating system should make choice
> #1 so that most hardware bought by most users work well with most
> applications. Getting 2% more applications or 20% more performance on the
> applications at the cost of 50% of the users not being able to use their
> hardware with decent performance is not the correct choice.
>

I find it hard to believe that Debian, as a universal operating
system, would sacrifice software and freedom because some 3rd party
software only supports GLES or that they implemented OpenGL poorly.

I do however understand that there is a time/effort trade off here. Qt
supports both already but only one or the other and currently not both
at the same time. My only question then becomes, what is going to
happen when support for Vulkan lands. Are we going to have the same
discussion? The work will eventually have to be done.

Cheers,
Bret