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. xpra itself is not really good at either proxying or accelerating glx/dri. > 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
