Multiple head cursor collision detection

[Mihai Draghicioiu]

Hi guys! I have a triple monitor setup (see
http://lists.freedesktop.org/archives/xorg/2011-January/052383.html
for more details), with the leftmost and rightmost monitors being
setup to be slightly below the middle monitor's top line (see
http://img819.imageshack.us/img819/5999/triplehead.png), and my
problem is that when i move the cursor along the top edge of the
middle monitor, and hit the right or left edge and the cursor is about
to enter one of the side monitors, instead of stopping at the right
edge of the middle monitor, the cursor y position is set to the top of
the side monitor. On Windows, the cursor stops at the edge of the
monitor, and to enter the lateral monitors, one has to lower the
cursor until it's low enough to enter the other monitor. Vertically,
this works fine. If the cursor is in one of the side monitors and i
try to move it upwards, it stops at the top edge of the monitor. If I
move the cursor along the top edge until it enters the middle monitor,
after it enters it, I can move it up some more until it reaches the
topmost edge of the middle monitor. This is correct, in my view. The
incorrect situation is when i move the cursor along the top edge of
the middle monitor and the y position is warped.

So my question is whether i can get this to work like it does in
Windows. This is more correct, in my opinion. This is also more
useful, because with my window manager (and others too, probably), i
can just move the cursor to the top right corner (and have it slide
along the edges until it hits the corner, so all i have to do is move
the mouse diagonally). Let me try to illustrate:
http://img218.imageshack.us/img218/7996/cursorn.png (the blue and
purple lines illustrate where the cursor ends up).

I hope my question is clear. I have a feeling that this has never been
implemented in X.

Thanks!