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View Full Version : Possible Driver bug, image tearing post 28.80


casey
04-08-03, 04:10 PM
I believe I have found a possible bug in all linux drivers post 28.80. I am running the gentoo 2.4.19 Kernel and i have tested the nvidia drivers downloaded from nvidias website via tarball:

28.80 (ok)
41.91 (broken)
43.49 (broken)

I have written a program using glut 3.7 which has a vertical scrolling line which is sync'ed to the vertical retrace (export __GL_SYNC_TO_VBLANK=1). The line breaks or tears in places when i run the program "hello" (modified from the "redbook" examples) on all drivers tested post 28.80. But no problems using the 28.80 driver. I have attached "thing.tar.zip" which contains my code hello.c, and my Makefile. Glut 3.7 is required to compile this program. thing.tar.zip has to be *.zip b/c of some silly file extention filter on this forum (LAME!). Just erase the .zip and "tar -zxvf thing.tar"

I believe the swapbuffer is not happening on the vertical retrace in all instances durring execution. Not sure why but i think its a bug in the Nv driver some place.

RT click to start line, LFT click to stop, BOTH click to exit prog.
Droped frames are printed to the console that you run hello from along w/ the delay in milli-seconds between swap buffers. make sure you set your "__GL_SYNC_TO_VBLANK=1" environment variable or your line will do like mach 3 and will tear in like 20 places.

-=Casey

I hope I an get some of you to evaluate and reproduce my symptoms here. Please let me know if you find anything or have ANY questions or need more info. Thanks in advance



:confused:

casey
04-08-03, 04:13 PM
PS: IM using the GF4 Ti 4600 and I have no idea why it says Rivia 128 next to my post.

sorry if this thread is in the wrong section.

-=Casey cjlancour@link.com

darkmiasma
04-08-03, 07:02 PM
Originally posted by casey
PS: IM using the GF4 Ti 4600 and I have no idea why it says Rivia 128 next to my post.

sorry if this thread is in the wrong section.

-=Casey cjlancour@link.com

the Riva 128 has to do with the number of posts you have, not what video card you use.

- mike