Bizarre graphics glitches with Ubuntu provided SDL2

[scrawl]

For a long time, I've been plagued by an annoying graphics issue that happened approximately 1 in 10 tries when starting the game. When this happened, in windowed mode, a portion of the window would not update correctly and would switch between old framebuffers instead. In fullscreen however, this would cause nothing to be rendered at all.

Because this was also happening to other non-OpenMW games and applications, and the sheer bizarreness of the issue, I chalked it up to being a video driver or hardware issue. Maybe a portion of the GPU memory was defect? I was just about to try replacing the card, however last night I finally managed to compile CUDA GPU Memtest and it confirmed that the card actually had no errors.

The next thing I suspected was either the compositing manager or SDL. I then uninstalled the SDL2 package from the Ubuntu repositories and compiled the latest version 2.0.5 from their website. Lo and behold, the problem is completely gone now!

I have no idea if this issue was somehow local to my system, but if it isn't, maybe this post will help someone. This all happened on Ubuntu 14.04 and the package I had installed was "libsdl2-2.0.0 2.0.2+dfsg1-3ubuntu1.1" from universe.

[psi29a]

Have you looked at the patches used in later ubuntu versions?

14.04 is 2.0.2+dfsg1-3ubuntu1
14.10,16.04 is 2.0.4+dfsg1-2ubuntu2
16.10 is 2.0.5+dfsg1-2ubuntu3

you can try backporting 2.0.5+dfsg1-2ubuntu3 to 14.04 and see if the problem was solved.

Code: Select all

sudo apt-get install ubuntu-dev-tools gnupg-agent

Code: Select all

backportpackage -s zesty -d trusty --dont-sign -b -w ./ libsdl2

^-- something like this, you'll have to fiddle and install the necessary dev packages.