Switching screens causes flicker and (sometimes) crash

[wolfger]

Steps to reproduce:
1) run memaker from cli
2) create an avatar
3) use mouse scroll wheel over KDE's pager to switch to a different desktop, then repeat process to go back to memaker's desktop
4) See avatar flicker in and out of existence. In the end it doesn't show again until you change something.
5) the first time I experience this, memaker crashed with the following command line output:

memaker.py:188: PangoWarning: Unable to open font file /usr/share/fonts/truetype/arphic/uming.ttf for font 文鼎PL細上海宋Uni 148.203125, falling back to /var/lib/defoma/fontconfig.d/D/DejaVu-Sans.ttf

  self.svgHandle.render_cairo(self.finalUpdate)
memaker.py:188: PangoWarning: Unable to open font file /var/lib/defoma/fontconfig.d/K/KochiGothic-Regular.ttf for font Kochi Gothic 148.203125, falling back to /var/lib/defoma/fontconfig.d/D/DejaVu-Sans.ttf

  self.svgHandle.render_cairo(self.finalUpdate)
memaker.py:188: PangoWarning: Unable to open font file /var/lib/defoma/fontconfig.d/D/Dotum-Regular.ttf for font Baekmuk Dotum 148.203125, falling back to /var/lib/defoma/fontconfig.d/D/DejaVu-Sans.ttf

  self.svgHandle.render_cairo(self.finalUpdate)

Pango-ERROR **: Unable to open font file /var/lib/defoma/fontconfig.d/D/DejaVu-Sans.ttf for font 文鼎PL細上海宋Uni 148.203125, exiting

aborting...
Aborted (core dumped)

[encompass (encompass)]

Very interesting.
Can you tell me if you are using any no engish fonts on your system?
And I presumer your running Kubuntu 7.10?

[wolfger (wolfger)]

Only English fonts. I am running Kubuntu 7.10
I have found that I can also reproduce the flicker simply by minimizing memaker or by switching focus to a different window which overlaps the memaker window. Flicker does not occur if the windows aren't overlapping. The duration of the flicker seems to be directly related to the number of features that have been drawn. The flicker itself produces no messages in the command window, and I have not been able to recreate the crash.

[wolfger (wolfger)]

Immediately after saying I couldn't recreate the crash, I switched desktops again and it crashed. The error output is different this time:

memaker.py:188: PangoWarning: Unable to open font file /usr/share/fonts/truetype/arphic/uming.ttf for font 文鼎PL細上海宋Uni 148.203125, falling back to /var/lib/defoma/fontconfig.d/D/DejaVu-Sans.ttf

  self.svgHandle.render_cairo(self.finalUpdate)
memaker.py:188: PangoWarning: Unable to open font file /var/lib/defoma/fontconfig.d/K/KochiGothic-Regular.ttf for font Kochi Gothic 148.203125, falling back to /var/lib/defoma/fontconfig.d/D/DejaVu-Sans.ttf

  self.svgHandle.render_cairo(self.finalUpdate)
memaker.py:188: PangoWarning: Unable to open font file /var/lib/defoma/fontconfig.d/D/Dotum-Regular.ttf for font Baekmuk Dotum 148.203125, falling back to /var/lib/defoma/fontconfig.d/D/DejaVu-Sans.ttf

  self.svgHandle.render_cairo(self.finalUpdate)
memaker.py:188: PangoWarning: Error loading GPOS table 64
  self.svgHandle.render_cairo(self.finalUpdate)
No fonts found; this probably means that the fontconfig
library is not correctly configured. You may need to
edit the fonts.conf configuration file. More information
about fontconfig can be found in the fontconfig(3) manual
page and on http://fontconfig.org

[encompass (encompass)]

Hmm.. I think this is a bug that only happens in KDE. As I have tried and can't get this problem on my computer, ubuntu, with no chance.
I would presume that this is an error on the side of pango, or closer, cairo.

[Christopher Denter (dennda)]

@ encompass: No.
That bug has happened to me too. I am on GNOME with Compiz and/or Metacity.
Sometimes at random, sometimes when I drag the window. It doesn't redraw properly, I take it.

[wolfger (wolfger)]

@dennda: Sounds like we have different (although possibly related) issues. I will see if I can get a movie file of what I am seeing, since it is hard to explain. Tonight or this weekend. (can somebody recommend a good screen capture program?)

[Andrew (and471)]

yep I can confirm it happens on Gnome with metacity (gtk-recordmydesktop is a good screencapture app)

[Pete Savage (petesavage)]

This is all linked to the cairo redraw problem. Trying to figure that out as we speak. It seems the redrawing isn't happening even after the expose-event. I'd fudged it......wrongly.

[wolfger (wolfger)]

video of the issue

[encompass (encompass)]

Is it fixed now? Hopefully I can close this bug. :/

[wolfger (wolfger)]

Close away.