Edit: Solved by installation of nvidia-libgl - probably obvious to some, but wasn’t to me! :-)
So I did a fresh install yesterday.
Installed antergos-base (no DE) then xorg then plasma-meta, sddm, kde-applications-meta, nvidia 352. (I just didn’t like the idea of having to install KDE4 then remove it to get Plasma 5.)
Eventually I wanted to start tweaking things, and I noticed that some of the desktop effects options weren’t listed. So I checked my kwin render settings, and they are as below. I can select either of the opengl options, but when I do it immediately reverts back to xrender. This isn’t reflected in the GUI right away, but if I exit the settings then come back in it’s clear - plus it doesn’t fix my issues.
I’m on a sandybridge laptop, but the intel GPU is motherboard disabled (at a hardware level as I understand it - I have no capability to turn it on) - so optimus is not the issue and I have never in 4 years needed to concern myself with it.
GPU is gtx460m
Nvidia driver as noted is 352.
I’ve googled quite a bit, and this is apparently a somewhat common problem. But every reference to this I found has been for KDE4.x, or the solution is not posted, or the solution did not apply to my hardware (some ATI/AMD issues).
I’m hoping that I skipped some obvious step, even though I consulted the Arch Wiki as needed along the way. (I haven’t run Arch nor Antergos in a pretty long time.) In any case, I really don’t know what I should be looking at to troubleshoot this.
I have run Plasma 5 on this hardware before and I’m 100% sure it’s not an issue of hardware capability because it has worked in the past.
Though it’s probably not needed, attached is an image of the settings dialog.
Thanks for any help!