I've recently configured a multi screen setup in my linux box.
So i decided to try out the multi screen functions provided by openoffice in
order to keep the presentation editor in the first screen while showing the
presentation on the second screen. But i was greeted by extremely bad
performances: pratically the animations are so slow that i can see only one
frame per second making them really bad.
So i did various tries and these were my results:
impress editor in screen 1 and presentation in screen 2: bad performance
impress editor in screen 2 and presentation in screen 1: bad performance
impress editor in screen 2 and presentation in screen 2: acceptable performance
impress editor in screen 1 and presentation in screen 1: acceptable performance
these were done with separate x screens (no xinerama) and it seems only in the
case the impress editor lies in a different screen can cause the problem
if i enabled xinerama support these problems disappeared and performance are
acceptable in any configuration but this isn't a solution!

===>>>To reproduce the problem just go in NVIDIA settings application and in x
server display configuration configure the second monitor to be on the right of
the first and as "Separate X screen" don't enable xinerama, save the xorg.conf
file and restart xserver. Then open openoffice impress and make a presentation
(whathever add a slide effect in the presentation wizard i used the latest
effect listed diagonal squares) then go to (translation from italian)
presentation => presentation setup and choose a the second monitor (different
than the one were the impress window is) and then try starting a presentation
you will notice extremely crappy performance for a modern computer.

This is my configuration
- Intel T7300 cpu @ 2ghz (dynamic cpu freq scaling)
- NVIDIA 8600 M GT gpu with 173.08 drivers
- an intel centrino duo overall architecture
- Ubuntu 7.10 gutsy
- kernel 2.6.25
- gnome 2.20.1 enviroment
- monitor one is 1280x800 (DVI internal link/TFT) , monitor two 1024x768 (VGA/CRT).
i will update to hardy in the next days so i will update the bug when i will be
able to check openoffice 2.4 but as i can't see anything related to double
monitors in changelogs and performance improvements lists most probably the
problem is still there.
Thanks for the attention.