[M6-LY] Gimp brushes leave garbage pixel trails

Binary package hint: gimp

I just upgraded from Ubuntu 6.10 to 7.10, and now Gimp has a horrible display artifact: every tool that uses a brush leaves bright green pixel trails across the image. Though they go away when the window refreshes (i.e. minimize and then restore the window), this makes Gimp essentially unusable for me.

This is with gimp-2.4.0~rc3-1ubuntu7.

A screenshot of the problem is here: http://img.photobucket.com/albums/v50/bitwise/Screenshot1.png

Thanks for your report, sadly i can't see the image, may you submit it to the report as an attachment? thanks.

I have attached the screenshot.

I have heard a rumor that this may have been encountered by Debian, and that it only appears in systems that have been upgraded (i.e. not clean installs), and also that the bug is actually due to xorg and gtk miscommunicating.

So far I have been unable to find any proof of this: mailing list messages, debian bugtracker entries, etc.

Someone saw this on Fedora: http://www.fedoraforum.org/forum/showthread.php?t=168979

It has a tantalizing reference to debian having identified and fixed the problem, but there's not enough information to identify what package was fixed. It does say, however, that an update landed in debian sid "this morning" (meaning 10/24/07, I think).

Here is a bug listing at gnome.org that describes the problem in a little more detail, and mentions a patch to Gimp that fixes the problem (though the underlying bug seems to be in xorg or gtk).

http://bugzilla.gnome.org/show_bug.cgi?id=421466

Here's a bug report at debian, and a mailing list message from gimp-user.

Looks like it's related to the ati video drivers; both I and the reporter have the same video card: an ATI Radeon 7000 / VE / RV100.

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=433230

http://<email address hidden>/msg12871.html

Here is a workaround for now. Put this in ~/.gimp-2.4/gimprc:

(show-brush-outline no)

I can confirm this works, but as you might guess, the whole brush outline goes away. When Gimp 2.4.1 is released, a slightly more sophisticated workaround will be present, where you can use:

(xor-color (color-rgb 1.0 1.0 1.0))

That will change the drawing mode gimp uses from XOR to INVERT, and the brush outline will work better.

These are just workarounds; new users are going to keep encountering this until the bug in the radeon driver is fixed:

https://bugs.freedesktop.org/show_bug.cgi?id=9877
https://bugs.freedesktop.org/show_bug.cgi?id=12853

I would like to add that the bug applies to Gimp 2.4.2 with both the ati and radoen driver.
The graphics card is ATI Radeon Mobility M6LY although the bug may apply to others, I've read the Radeon 7200 is affected as well.

I just like to point out that this bug still exists in hardy beta GIMP 2.4.5 and that adding

(xor-color (color-rgb 1.0 1.0 1.0))

to the gimprc fixes it.

I just found out, that this bug does not show if the option "AccelMethod" "EXA" in xorg is enabled. Sadly, this results in painfully slow konqueror performance while accessing uncached folders.

 This is certainly an xorg problem. Both using xgl and Xephyr servers solved the problem. Unfortunately, there is no longer 3D acceleration on my ati mobility u1 card so xgl doesn't feel right, and I was unable to configure xephyr as the only graphics server. Can run gimp in a Xephyr window, but it's no good.

And adding

(xor-color (color-rgb 1.0 1.0 1.0))

to the gimprc in gimp 2.4.2 fixes it.

I also experience this problem. Confirming.

Does anyone see this with the fglrx driver?

Thanks for taking the time to report this bug and helping to make Ubuntu better. In the development cycle for Intrepid there have been some vast improvements in the open source ati video driver and we could use your help testing them. Could you please download the latest Alpha CD image of Intrepid and test this particular bug just using the Live CD? You can find the latest image at http://www.ubuntu.com/testing . Your testing can help make Ubuntu and the open source ati driver even better! Thanks in advance.

Unfortunately, this still happens in Intrepid with a radeon card, despite the changes in the new ati driver. But adding

(xor-color (color-rgb 1.0 1.0 1.0))

to the gimprc in gimp 2.4.2 still fixes it.

I can confirm this in intrepid (up to date as of about an hour ago) on a thinkpad x31. 'radeon' driver, Gimp 2.6.1.
I have had it since i started using ubuntu 3 or 4 versions back.

I'll try the "(xor-color (color-rgb 1.0 1.0 1.0))" trick and see if it works with this version of GIMP.

Thanks, hope this will eventually get fixed!

Just to update, appending "(xor-color (color-rgb 1.0 1.0 1.0))" to "/home/<user>/.gimp-2.6/gimprc" DOES work in intrepid (gimp2.6.1,radeon driver, etc) on my TPx31.
Thanks :)

Might try setting Option "AccelDFS" "false" in /etc/X11/xorg.conf's display section.

I see that gimp is marking this bug resolved, and there's been no recent comments that this is still an issue, so I'm going to tentatively and optimistically close this bug as no longer an issue. It seems to be an XAA-specific issue.

If it can still be reproduced on current Lucid using EXA, please re-open the upstream bug.