Re: Projector Wall
Thanks for posting, Jaxxon,
I can do some Twinview if I want -- I'm using three 9800 GTs to get six video outputs. Earlier in my testing (very early on) I tried Twinview + Xinerama and still noticed it I think, but I may revisit that.
I've spent about the last 8 hours straight in lab trying all the permutations of Nvidia X config settings and several Xgl settings right now. Several driver versions (180.60, 169.12, 173.something), switching from kernel 2.6.24 to 2.6.29, to no avail.
I'm pretty good at reproducing the problem now. Did you watch my video? It is much more blatant if I simply initiate an Xgl window inside of a normal Xinerama-only X session and lay it across a boundary between video outputs. If I do that and spawn a terminal inside, the terminal will not redraw correctly across the boundaries. I could produce a better video now.
I have not found very much googling around. One guy over on the Ubuntu forums mentioned he had smearing like mine, but it went away with Compiz. In my case, Compiz does not appear to be obtaining the correct texture for the window contents perhaps. Or maybe, rather, the video card does not think it is receiving the right texture. It seems like a subtle redraw issue.
I've tried the GlyphCache and InitialPixmapPlacement nvidia-settings options also (they've fixed the weird terminal redrawing problems on my laptop and a Mac mini in my lab in the past), but they did not change anything for me here.