Renewed Work Around GNOME 30-bit Deep Color Frame-Buffer Support

[phoronix]

Phoronix: Renewed Work Around GNOME 30-bit Deep Color Frame-Buffer Support

Going back years has been an effort to get 30-bit deep color support on the GNOME desktop under Wayland. Ubuntu and others have been interested in getting 30-bit color support working nicely for the Linux desktop, but while that milestone hasn't yet been crossed, thankfully there is some renewed work in that direction...

https://www.phoronix.com/news/GNOME-Deep-Color-30-bit-August

[tachi]

Why is this important?

[FireBurn]

Why is this important?

It's the first step in getting HDR working

[david-nk]

I'm pretty sure most applications still draw their stuff in XRGB8888 format, so for SHM clients a full copy+conversion will be necessary. Though I haven't benchmarked the effective frame rate loss yet. Perhaps it's not that bad, memory keeps getting faster, especially with DDR5 coming.

[uid313]

What about 36 and 48 bit color?

Why is this important?

I think for HDR and for medical imaging.

[Danny3]

Can someone explain it it in 8/10 bit color terms?

Is this the same as in KDE Plasma that got in versio n 5.24 the ability to display more than 8bit color, which I assume it's 10bit colors?

https://www.omgubuntu.co.uk/2022/02/kde-plasma-5-24-released-this-is-whats-new

And if it's good for HDR, anyone knows how far are we from it in both Gnome and KDE Plasma?

[MastaG]

It will take another 5 years until I can select 10bpc in the settings panel.

[MrCooper]

I'm pretty sure most applications still draw their stuff in XRGB8888 format, so for SHM clients a full copy+conversion will be necessary.

What conversion? It's just different sampler/output formats for the same drawing operations which would happen anyway.

Though I haven't benchmarked the effective frame rate loss yet. Perhaps it's not that bad, memory keeps getting faster, especially with DDR5 coming.

It's the same memory bandwidth, 4 bytes per pixel either way. I'd be surprised if there was any measurable difference in performance (or energy consumption).

[caligula]

Why is this important?

Linux users aren't that poor anymore. Somebody can now afford a $239 screen these days and wants to take advantage of its full potential. Maybe they'll buy used ones from Windows users. Anyway. https://www.amazon.com/SAMSUNG-Monit.../dp/B09ZH75WR7

[carewolf]

Can someone explain it it in 8/10 bit color terms?

Is this the same as in KDE Plasma that got in versio n 5.24 the ability to display more than 8bit color, which I assume it's 10bit colors?
https://www.omgubuntu.co.uk/2022/02/...s-is-whats-new
And if it's good for HDR, anyone knows how far are we from it in both Gnome and KDE Plasma?

8bit means 8bit per color channel (256 levels of each base color) so 24bit in total (or 16 milion colors). This has traditionally been good enough, but if you start showing brighter whites or showing a lot of darker colors, 8 bits per color become noticable insufficient, in that you can see clear edges where two adjacent colors meet. So instead you can use 10bits per color or 30 bits in total (for 1 billion colors), this still fits the three colors inside a 32bit value, but is more precise, and better for HDR to have room for the really bright stuff or for screens that needs to show tiny variants in dark areas (like medical imaging systems).