graphical glitches?

[liamdawe]

Any idea why I am getting these graphics glitches and how to stop them? Is it a known bug?

You can see the weirld lines going through my panel.

[Teunis]

Yes I can see the weird stuff in your panel.

But to say anything more you'll first have to supply us with information about the hardware (video card) you are running, the drivers installed and information about having 3D enabled or not.

[liamdawe]

Intel HD 4000 (Ivybridge). How do I know if 3D is enabled or not?

[benny_fletch]

KMenu -> Applications -> System -> KInfocenter then Graphical Information -> OpenGL

In the past I have found this section will not open or throw an error if 3D/OpenGL Compositing isn't enabled/configured correctly. If it does open, let us know what it says for the following sections:
3D Accelerator -> Device
Driver -> Renderer
Driver -> Kernel module

Also, have you tried another Desktop Theme to see if it has the same issue?

You could also try using XRender instead of OpenGL ( SystemSettings -> Desktop Effects -> Advanced Tab -> Compositing type: )

[liamdawe]

3D Accelerator -> Device - 3rd Gen Core processor graphics controller
Driver -> Renderer - mesa dri intel ivybridge mobile
Driver -> Kernel module - i915

What's the difference between xrender and opengl?

[benny_fletch]

Good question (and hopefully someone will correct me if I am wrong), but from what I understand xrender is a 3D/Compositing layer built into the X11 window system (Xorg) where as OpenGL is a 3D/Compositing layer that is built in/used in the Mesa video drivers (i.e. a third party plug-in of sorts). They both achieve a similar effect. OpenGL has more capabilities when it comes to 3D rendering though (and is a direct replacement for DirectX in Windows systems) where as Xrender is more of a work around instituted by Xorg. A more detailed explanation I do not have (sorry). Here are the links to their perspective wikipedia pages:
http://en.wikipedia.org/wiki/X_Rendering_Extension
http://en.wikipedia.org/wiki/OpenGL

The only reason I ask is some video cards work better with OpenGL and some work better with Xrender. Especially so with some Intel video cards. I would be worth trying if you are experiencing issues with OpenGL (i.e. slow rendering, graphical artifacts, etc.).

[KeithZG]

For the record, I get the same issue with persistently recurring (every time I open or move windows, basically) graphical glitches (although at the top of my screen rather than the bottom). Switching to XRender does away with the issues, although then also disables some of the desktop effects I use.

My setup:
Intel i5-3550 on an H61 motherboard (specifically an MSI H61M-P31)
KInfoCenter (and lspci) claim my graphics adapter is a Xeon E3-1200 v2/3rd Gen . . . which I guess is correct? And are these newer adapters really still under the old i915 module? I suppose that's probably all fine (they've been using that module forever now, and many latter-day drivers have been under it).