Re: Review: FULLSCREEN_MONITORS Hint

[Grant Patterson <grantp vmware com>]

Dana Jansens wrote:
>  >
>  > _NET_WM_FULLSCREEN_MONITORS, CARDINAL[]/32
>
> Other hints with a fixed list size would describe this as:
>   _NET_WM_FULLSCREEN_MONITORS, CARDINAL[4]/32
>
>  Maybe this should do the same for consistency.

Sure.
>  >  ]]></programlisting>
>  >        <para>
>  >  A read-only list of 4 monitor indices indicating the top, bottom, left, and
>  >  right edges of the window when fullscreened. The indices are from
>
>
> "when the fullscreen state is enabled" or something might be better
>  here.  Fullscreened isn't really an adjective.
Fixed.
>  >  An empty list indicates that the Window Manager will obey normal fullscreen
>  >
>  > conventions, as if the property did not exist.
>
>
> Why do you specify this behavior, as opposed to just having the
>  property removed from the window entirely?
This is just left over from when we listed all monitors to be included; I've 
removed it.

>  >    other data.l[] elements = 0
>
>
> There are no other data.l[] elements, only 5.  That said, the data.s[]
>  elements should be more than enough and allow for more things to be
>  added in the future, but I realize every other hint exclusively uses
>  data.l[].  Anyone else have an opinion about this?
I like the idea of using the 16-bit elements so there's room for expansion. 
While I can't see any reason for this now, there might be some flags an app 
would want to set to further define window manager behavior. Changed.

New hint:


    <sect2>
		<title>_NET_WM_FULLSCREEN_MONITORS</title>
		<programlisting><![CDATA[
_NET_WM_FULLSCREEN_MONITORS, CARDINAL[4]/16
]]></programlisting>
      <para>
A read-only list of 4 monitor indices indicating the top, bottom, left, and
right edges of the window when the fullscreen state is enabled. The indices
are from the set returned by the Xinerama extension.
      </para>
      <para>
Windows transient for the window with _NET_WM_FULLSCREEN_MONITORS set, such as
those with type _NEW_WM_WINDOW_TYPE_DIALOG, are generally expected to be
positioned (e.g. centered) with respect to only one of the monitors. This
might be the monitor containing the mouse pointer or the monitor containing the
non-full-screen window.
      </para>
      <para>
A Client wishing to change this list MUST send a _NET_WM_FULLSCREEN_MONITORS
client message to the root window. The Window Manager MUST
keep this list updated to reflect the current state of the window.
      </para>
<programlisting><![CDATA[
  window  = the respective client window
  message_type = _NET_WM_FULLSCREEN_MONITORS
  format = 16
  data.s[0] = the monitor whose top edge defines the top edge of the fullscreen 
window
  data.s[1] = the monitor whose bottom edge defines the bottom edge of the 
fullscreen window
  data.s[2] = the monitor whose left edge defines the left edge of the 
fullscreen window
  data.s[3] = the monitor whose right edge defines the right edge of the 
fullscreen window
  data.s[4] = source indication
  other data.s[] elements = 0
]]></programlisting>
      <para>
See <xref linkend="sourceindication"/> for details on the source indication.
      </para>
      <para>
Virtual machine software may use this hint to have a virtual operating system
instance that sees multiple monitors. The application window stretches over
several monitors, giving the appearance that these monitors have been taken
over by the guest virtual machine.
      </para>
      <para>
This hint might also be used by a movie or presentation application allowing
users to display the media spanned over several monitors.
      </para>
      <para>
In both cases, the application would have some user interface allowing users
to configure which monitors the application fullscreens to. The window manager
need not provide such an interface, though it could.
      </para>
      <para>
In the event of a change in monitor configuration, the application is
responsible for re-computing the monitors on which it wants to appear.
The window manager may continue using the same monitor indices as before
or simply clear the list, returning to "normal" fullscreen.
      </para>
   	</sect2>

--- ../wm-spec-old.xml	2007-10-19 13:52:44.773627000 -0700
+++ wm-spec-1.4.xml	2008-03-04 18:55:55.613681000 -0800
@@ -1629,6 +1629,64 @@
 window.
 		</para>
 	</sect2>
+    <sect2>
+		<title>_NET_WM_FULLSCREEN_MONITORS</title>
+		<programlisting><![CDATA[
+_NET_WM_FULLSCREEN_MONITORS, CARDINAL[4]/16
+]]></programlisting>
+      <para>
+A read-only list of 4 monitor indices indicating the top, bottom, left, and
+right edges of the window when the fullscreen state is enabled. The indices
+are from the set returned by the Xinerama extension.
+      </para>
+      <para>
+Windows transient for the window with _NET_WM_FULLSCREEN_MONITORS set, such as
+those with type _NEW_WM_WINDOW_TYPE_DIALOG, are generally expected to be
+positioned (e.g. centered) with respect to only one of the monitors. This
+might be the monitor containing the mouse pointer or the monitor containing the
+non-full-screen window.
+      </para>
+      <para>
+A Client wishing to change this list MUST send a _NET_WM_FULLSCREEN_MONITORS
+client message to the root window. The Window Manager MUST
+keep this list updated to reflect the current state of the window.
+      </para>
+<programlisting><![CDATA[
+  window  = the respective client window
+  message_type = _NET_WM_FULLSCREEN_MONITORS
+  format = 16
+  data.s[0] = the monitor whose top edge defines the top edge of the fullscreen window
+  data.s[1] = the monitor whose bottom edge defines the bottom edge of the fullscreen window
+  data.s[2] = the monitor whose left edge defines the left edge of the fullscreen window
+  data.s[3] = the monitor whose right edge defines the right edge of the fullscreen window
+  data.s[4] = source indication
+  other data.s[] elements = 0
+]]></programlisting>
+      <para>
+See <xref linkend="sourceindication"/> for details on the source indication.
+      </para>
+      <para>
+Virtual machine software may use this hint to have a virtual operating system
+instance that sees multiple monitors. The application window stretches over
+several monitors, giving the appearance that these monitors have been taken
+over by the guest virtual machine.
+      </para>
+      <para>
+This hint might also be used by a movie or presentation application allowing
+users to display the media spanned over several monitors.
+      </para>
+      <para>
+In both cases, the application would have some user interface allowing users
+to configure which monitors the application fullscreens to. The window manager
+need not provide such an interface, though it could.
+      </para>
+      <para>
+In the event of a change in monitor configuration, the application is
+responsible for re-computing the monitors on which it wants to appear.
+The window manager may continue using the same monitor indices as before
+or simply clear the list, returning to "normal" fullscreen.
+      </para>
+   	</sect2>
 </sect1>