<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [ilk] Font and screen corruption in GTK+ applications" href="https://bugs.freedesktop.org/show_bug.cgi?id=88584#c17">Comment # 17</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [ilk] Font and screen corruption in GTK+ applications" href="https://bugs.freedesktop.org/show_bug.cgi?id=88584">bug 88584</a> from <a class="email" href="mailto:psychonaut@nothingisreal.com" title="Tristan Miller <psychonaut@nothingisreal.com>"> Tristan Miller</a> <pre>(In reply to Orion Poplawski from <a href="show_bug.cgi?id=88584#c16">comment #16</a>) > Any progress here? Anything that can be done to help? This machine is > becoming pretty unusable. If you follow the link to the openSUSE bug from my original report, you'll find that two workarounds have been suggested (one from Stefan Dirsch in <a href="show_bug.cgi?id=88584#c5">Comment #5</a> and one from Egbert Eich in <a href="show_bug.cgi?id=88584#c7">Comment #7</a>). The first one seems to have worked for me; the second one I haven't tested. I reproduce Egbert Eich's comment here, as it contains technical information which may be of use to the Intel driver developers: > I've chased this issue on Intel Ilk for weeks. This is the same gen > as you have used for the log you posted on fd.o. I don't know which > other GPUs you have used. > > I've been able to trace this to the 2D textures COGL uses to store > glyphs and icons in (as sub-textures) called 'atlases': when a new > object needs to be cached, COGLS tries to find room in the current > atlas. If there is no room it tries to resize the atlas. If the > maximum size of the texture is reached it creates a new 'atlas'. > > What I found was, that once the texture size exceeded 4kx4k (the > i965_dri.so driver announces a max texture level of 14 - ie. a size > of 8kx8k) the content got corrupted, ie some elemends got lost during > copying. However, what I also found was that this depended on the > blit mode used for atlases: the blit modes can be specified with the > environment variable COGL_ATLAS_DEFAULT_BLIT_MODE - available > settings are: 'texture-render'. 'framebuffer', 'copy-tex-sub-image', > 'get-tex-data'. 'texture-render' is the default. Specifying any of > the others made the issue go away for me. > > I've never gotten around to dump the opengl state and shaders used in > this mode to generate a simple test case which would have allowed to > debug the intel driver. > > The workaround I suggested to our customer was to set the environment > variable: > > COGL_ATLAS_DEFAULT_BLIT_MODE=framebuffer > > in /etc/environment. This made things work for him > > You may want to give this a try as well. > > Please let me know if it does the job.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>