Constraining cursor to RandR crtcs

[Colin Guthrie]

Keith Packard wrote:
> On Mon, 2007-04-02 at 10:49 +0100, Colin Guthrie wrote:
> 
>> I had the following layout
>> +---------------------------------+---------------------------------+
>> |                                 |                                 |
>> |                                 |                                 |
>> |                                 |                                 |
>> |                                 |                                 |
>> |                                 |                                 |
>> |                                 |                                 |
>> |                              3  | 4                               |
>> +---------------------------------+                                 |
>>                                   |                                 |
>>                                   |                                 |
>>                                2  | 1                               |
>>                                   +---------------------------------+
>>

> The other alternative is to just confine the cursor to the visible
> region in this case -- make it 'impossible' to move from 1 to 2, and
> just block the cursor at 1. That seems better to me, and makes it much
> more like the existing root window where you simply cannot move outside
> of the window at all.

Hmm, nice idea. Yes I like that I think.

> What would remain with this solution is a way to get between disjoint
> areas of the screen -- two CRTCs separated by a blank space would become
> effectively isolated.

Yeah, that is indeed a problem. I guess you have to ask why things would
be configured this way tho (with blank space separation). If someone
chooses to configure their display in this way it is possibly
(probably?) because one of their displays is dedicated for something -
e.g. presentations, video, TV etc. and the mouse is not really needed on
that area anyway. In such circumstances it could be the window manager's
job to do any switching of mouse from screen to screen via some keyboard
shortcut (e.g. modifier+scroll up/down or modifier+key up/down)

I'm probably guessing/assuming wildly here, but how often is it that
there are gaps (or that there /needs/ to be gaps) in the display areas?


Or perhaps the simpler (conceptually) solution is just to make it
impossible to define areas with a gap? What is lost if this is the case?

Col.