On 17/02/2020 15:51, Ilya Anfimov wrote: > On Sat, Feb 15, 2020 at 12:32:15AM +0700, Antoine Martin wrote: >> On 14/02/2020 18:53, Marek Szuba wrote: >>> Hello, >>> >>> I do quite a lot of photo editing on my box and with both my monitors >>> and my graphics card (amdgpu) supporting 10-bit colour channels, I tend >>> to run X at colour depth 30. Unfortunately some software, most notably >>> programs using OpenGL it seems, refuse to run in this mode - presumably >>> (I have seen this mentioned as the reason of problems with 30-bit mode >>> under Windows when the first cards supporting it came out) because the >>> software assumes 8-bit alpha channel but with the frame buffer still >>> being only 32-bit it is only 2-bit. Seeing as there seem to be no way of >>> switching colour depth on the fly, the best I have been able to come up >>> with is two separate X sessions - one at depth 30 and one at 24. >>> >>> Is there, or perhaps will there be some way in the near future, to work >>> around this problem - either by increasing framebuffer BPP (tried it a >>> while ago but it didn't seem to accept anything more than 32), using a >>> virtual X server (tried using Xephyr but it complained about there being >>> no matching screen), or some other way I haven't thought of? >> If you don't mind the indirection this introduces: >> xpra start --start=xterm --attach=yes >> This will start your application (ie: xterm) on a 24-bit virtual >> framebuffer and display it on your local 30-bit display. > > And with software-only OpenGL. If you want accelerated OpenGL within the xpra session, use VirtualGL: https://xpra.org/trac/wiki/Usage/OpenGL ie: xpra start --start="vglrun xterm" --attach=yes > xpra itself is not really good at either proxying or accelerating > glx/dri. Xpra doesn't even attempt to do these things, that's not its job.
Antoine > > > >> The pixel depth upscaling will be done by your OpenGL driver, or failing >> that, in software. >> >> The reverse is also possible, with a local display at 24-bit: >> xpra start --start=xterm --attach=yes --pixel-depth=30 >> Runs the app on a 30 bit virtual display. >> Apparently, there are apps that require a 30-bit display to use GPU >> image processing and some users don't care if they don't actually see >> the extra bit depth when doing so. >> >> Antoine >> >>> >>> Thank you in advance for your comments. >>> >> >> _______________________________________________ >> xorg@lists.x.org: X.Org support >> Archives: http://lists.freedesktop.org/archives/xorg >> Info: https://lists.x.org/mailman/listinfo/xorg >> Your subscription address: %(user_address)s _______________________________________________ xorg@lists.x.org: X.Org support Archives: http://lists.freedesktop.org/archives/xorg Info: https://lists.x.org/mailman/listinfo/xorg Your subscription address: %(user_address)s