With OpenGL disabled after zooming in/out with the mouse wheel (from min to max and vice-versa), the canvas is not automatically refreshed so "tile" artifacts appear on screen. Everything goes back to normal clicking on an item of the drop-down menu.
I am also experiencing something similar. I am on Ubuntu 14.04 with Krita on git master (from source). It appears related to OpenGL in some way. There is something with the fragment(tile) redrawing. The filtering seems to play some part in it as well. Tri-linear and highest quality filtering don't seem to have this issue. Here is a quick unlisted screen capture of my experience. https://www.youtube.com/watch?v=Ntrnv7iWBcY&feature=youtu.be
Which gpu/driver? I am pretty sure that for the opengl issue, it's a driver thing. I cannot explain (or reproduce) a refresh issue when opengl is disabled.
With my nvidia card I can reproduce the issue with nearest/bilinear.
I think I fixed both opengl-related issues. I'm still not able to reproduce the non-opengl issue -- besides, that report dates from before the commit that caused this bug.
great. I just pulled lastest and it fixed the OpenGL issues. Thanks Boud!
...But it doesn't fix the issue with non-OpenGL canvas... ^^
I tried with a Nvidia 9500GT with closed and open source driver but I got the same result...
Yes -- and I really wonder what's up there. The non-opengl canvas can't be influenced by graphics cards so Scott's report actually was a completely different bug. Could you perhaps make a screenshot for me?
Created attachment 87967 [details] Non-OpenGL Bug Screenshot
I've just uploaded a screenshot in attachment... ^^
Thanks! I still don't know what causes this, though, it's a total mystery. What's the linux you're using, and which version of Qt?
I'm on Xubuntu 14.04.1 lts... Compiling Krita I read "found Qt-Version 4.8.6" and the package version is 4.8.5+git192-g085f851+dfsg-2ubuntu4...
I have Kubuntu 14.04 and I don't have the non-opengl bug. Have you tried if different images have the same problem? For example if you create a new image vs opening an existing one.
Yes, I tried. Same problem with a new picture or opening an existing one.
I actually could reproduce this a couple of times -- it doesn't happen every time, for me at least.
*** Bug 339619 has been marked as a duplicate of this bug. ***
Also the last build (07/11/2014) has the same problem
do not consider the comments above! It refers to another bug. sorry
The bug also happens in 2.9.7. on windows: https://twitter.com/smdmg/status/711955473168084992
I'm sorry, but the QPainter canvas only exists for backup, and the OpenGL code has been rewritten multiple times since 2016, so I am going to close this bug, since it's confusing to have two issues in one bug report.