[PATCH wayland-protocols] xdg-shell: Introduce xdg_toplevel capabilities

[Quentin Glidic]

On 15/07/2016 13:00, Jonas Ådahl wrote:
> The xdg_toplevel capabilities are meant to let the compositor know what
> configurations a client can be configured to. This is meant to make it
> possible to disallow a compositor to maximize, fullscreen etc a
> surface, which would otherwise mandate the client to configure the
> surface according to dimension in the xdg_toplevel.configure event.
>
> This makes it possible to create non-resizable surfaces as well as
> surfaces with only a certain aspect ratio allowed, by making them
> un-fullscreen:able and un-maximize:able.
>
> Signed-off-by: Jonas Ådahl <jadahl at gmail.com>
> ---
>
> This is an alternative solution to the s/must/should/ patch.
>
> I made a separate enum, because certain state enum entries make no sense to
> support or not, since they don't mandate anything (resize, activated so far).
>

I like this idea better than the s/must/should/ patch.

Since we do not reuse the existing enum, does that make sense to group 
similar features?
The fullscreen/maximized/tiled states are about obeying an arbitrary 
size, you can still support even if you do nothing more. Sure, a 
fullscreen surface would look weird with a title bar, but it is usable, 
and will be on top of everything, just like intended.
Thoughts?

Nit: it should be <request> not <entry>. ;-)

Cheers,

> Jonas
>
>  unstable/xdg-shell/xdg-shell-unstable-v6.xml | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
>
> diff --git a/unstable/xdg-shell/xdg-shell-unstable-v6.xml b/unstable/xdg-shell/xdg-shell-unstable-v6.xml
> index 563e39b..73944a8 100644
> --- a/unstable/xdg-shell/xdg-shell-unstable-v6.xml
> +++ b/unstable/xdg-shell/xdg-shell-unstable-v6.xml
> @@ -734,6 +734,29 @@
>        </entry>
>      </enum>
>
> +    <enum name="capabilities">
> +      <description summary="toplevel capabilities">
> +	Certain xdg_toplevel states mandate certain client capabilities. For
> +	example while a fullscreen:ed client is required to configure itself
> +	according to the dimension in the configure event, some clients may not
> +	have this ability due to various reasons.
> +      </description>
> +      <entry name="maximize" value="1"
> +	     summary="the toplevel can be maximized"/>
> +      <entry name="fullscreen" value="2"
> +	     summary="the toplevel can be fullscreened"/>
> +    </enum>
> +
> +    <entry name="set_capabilities">
> +      <description summary="set capabilities">
> +	Notify the compositor about what capabilities this xdg_toplevel
> +	supports. This request can only be issued once and if so must be done
> +	before the initial state is comitted. The default capabilities are no
> +	capabilities.
> +      </description>
> +      <arg name="caps" type="array" summary="array of toplevel capabilities"/>
> +    </entry>
> +
>      <request name="set_max_size">
>        <description summary="set the maximum size">
>  	Set a maximum size for the window.
>


-- 

Quentin “Sardem FF7” Glidic