Display Bug & Crash with ATI cards and AA (1.6)

Report bugs, bug fixes and workarounds here.
Topic author
phoenix
Posts: 214
Joined: 18.06.2002
With us: 22 years 5 months
Location: Germany - Berlin

Display Bug & Crash with ATI cards and AA (1.6)

Post #1by phoenix » 17.02.2009, 00:49

hello there,

after a while of absence i got back to compiling me a latest svn release yesterday (r4651).
since the last time my computer specs have changed a bit and i upgraded all my old nvidia cards with ati cards.

build was fine and celestia runs fine but when I enable antialiassamples in config or through CCC i see this:
Image

as you can see the once beautiful asteroid-belt has turned into a weird blob of grey and my usually 60 FPS (synced to tft) turn into a slideshow.
i tried x2, x4 and x8 which only gets worse.
the problem only persists with opengl 2.0 render path and only with that asteroid belt.
as soon as i leave it's sight everything is back to normal again.

after tweaking every possible 3d-setting in CCC enabling "catalyst A.I." to "advanced" will crash celestia upon start without an error, it just drops back to windows and does nothing.

tested both on windows xp pro 32 bit with an HD3870 and HD4670 with same results on two different intel machines.
here's the opengl info for the 3870 if it helps.
most recent celestia win32-SVN-build - use at your own risk (copy over existing 1.5.1 release)

chris
Site Admin
Posts: 4211
Joined: 28.01.2002
With us: 22 years 9 months
Location: Seattle, Washington, USA

Re: Display Bug & Crash with ATI cards and AA (1.6)

Post #2by chris » 20.02.2009, 18:27

This is a problem with the ATI OpenGL driver's and support for point sprites, which are used in the asteroid belt add-on. Quite simply, the newer ATI drivers seem to have completely broken point sprite support on all platforms. The sizing of the sprites is completely wrong: instead of tiny points, the sprites are huge blobs. Drawing tens of thousands of these blobs is slowing down rendering to a crawl.

Does the problem go away when antialiasing is disabled?

--Chris

Topic author
phoenix
Posts: 214
Joined: 18.06.2002
With us: 22 years 5 months
Location: Germany - Berlin

Re: Display Bug & Crash with ATI cards and AA (1.6)

Post #3by phoenix » 20.02.2009, 18:48

yes, no AA = no problem ;)
most recent celestia win32-SVN-build - use at your own risk (copy over existing 1.5.1 release)

chris
Site Admin
Posts: 4211
Joined: 28.01.2002
With us: 22 years 9 months
Location: Seattle, Washington, USA

Re: Display Bug & Crash with ATI cards and AA (1.6)

Post #4by chris » 20.02.2009, 18:54

phoenix wrote:yes, no AA = no problem ;)

Interesting! This information might lead to a workaround for the ATI point sprites problem. Can you post a screenshot with AA disabled?

--Chris

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Re: Display Bug & Crash with ATI cards and AA (1.6)

Post #5by Cham » 20.02.2009, 21:16

phoenix wrote:yes, no AA = no problem ;)

FSAA is enabled on my ATI machine. I never switched it OFF to test my sprites models before. I may try some test this weekend to see if there's any differences...
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

Topic author
phoenix
Posts: 214
Joined: 18.06.2002
With us: 22 years 5 months
Location: Germany - Berlin

Re: Display Bug & Crash with ATI cards and AA (1.6)

Post #6by phoenix » 21.02.2009, 09:53

with no AA it looks just normal:
Image
most recent celestia win32-SVN-build - use at your own risk (copy over existing 1.5.1 release)


Return to “Bugs”