RFC : xdg_surface_present() look-and-feel and implementation

[Bill Spitzak]

On 07/29/2014 11:40 AM, Manuel Bachmann wrote:

> When creating a xdg_surface, the surface will not be mapped (i.e. shown)
> by desktop-shell anymore. It will only be if xdg_surface_present() has
> been called once.

There seems to be a design goal in Wayland to prevent clients from 
making surfaces that they never map. So it would be better if creation + 
commit of a surface did the same thing as present. Also this does not 
break existing clients.

There is nothing special about the first time the surface wants 
attention (other than historical legacy). The desktop should be allowed 
to turn this into a notification just like it would on subsequent calls.

> If called twice, or more, the request will send an event to
> desktop-shell, so it can display a notification.

This is not controlled by a count, but by whether a window is already 
visible or already in the notification state. Clients should be able to 
send a lot of these in a row. They cannot reliably test if they are 
invisible and send the request only then, as there is a race condition.

I also think the term "present" is not a great idea. This should be 
exactly the same as "raise" or "show" or "activate" or any number of 
other terms, but I have never seen the word "present" used before. I 
would reuse an existing term. One reason is to prevent somebody else 
from adding a redundant api for that term, because they did not realize 
"present" is the thing they are looking for.