Constraining cursor to RandR crtcs

[Colin Guthrie]

Andy Ritger wrote:
> NVIDIA's TwinView implementation suffers from the same problem --
> that the cursor can be in a region of the screen that is not visible.
> I don't think I've seen many user complaints from that.  I assume users
> just wiggle the mouse around until it finds its way back into a visible
> portion of the screen.

I remember when I was using an nvidia twinview setup and I had this
"issue" too.

I had the following layout
+---------------------------------+---------------------------------+
|                                 |                                 |
|                                 |                                 |
|                                 |                                 |
|                                 |                                 |
|                                 |                                 |
|                                 |                                 |
|                              3  | 4                               |
+---------------------------------+                                 |
                                  |                                 |
                                  |                                 |
                               2  | 1                               |
                                  +---------------------------------+


If I moved the mouse from point 1 to point 2, the cursor would be hidden
from me. I did indeed just wiggle it until I could see it again.

If the mouse were to warp from point 1 to point 3 as I moved it towards
point 2, then this would have been nice I think. However, if I had just
moved the mouse one tiny pixel into the dead space when I didn't mean
to, (e.g. some app on the right screen had a button at it's bottom left
corner) and subsequently moved it back to the right screen only to find
my cursor now in point 4, I would have found this quite annoying.

Unless moving from 1 -> 2 (warp) 3 -> back towards 4 quickly -> (unwarp)
1 happened (e.g. with some sort of fuzziness to determine when to
"unwarp" then I could see it getting quite annoying.

So while I like the principle of the auto-warp, I think it needs to be
done flexibly to allow user control (e.g. turn it off) and also to have
some degree of intelligence (with configurable thresholds etc.

Just my €0.02

Col.