Then when a game is started it starts another Gamescope session which launches the game in a second XWayland session.

No, it doesn’t start another gamescope. It starts a second Xwayland in the same gamescope instance.

TV manufacturers are part of the cartel HDMI forum, which benefits from there being a big ecosystem of non-member devices that are forced to have HDMI ln them and pay licensing fees for it.

NVidia still hasn’t implemented support for adaptive sync with multiple monitors in their driver. If you can connect the second screen to the integrated GPU, that would work though

That’s because Windows has a system provided toolkit that most apps use

long press for imitating a right click, but text selection with popup copy/paste/etc buttons would also be useful.

Unfortunately that’s not something that can be done system wide, apps have to handle that themselves.

afaik not packaged for any distro

It’s packaged in every widely used distro.

I understand that it’s an absolute brightness standard, not like the relative levels in SDR

The standard is also relative brightness actually, though displays (luckily) don’t implement it that way.

why does it end up washing out colors unless I amplify them in kwin? Is just the brightness absolute in nits, but not the color?

It depends. You might

• have a driver bug. Right now only AMD has correct color space communication with the display, that doesn’t work correctly on Intel and NVidia yet
• have a display that does a terrible job at mapping the rec.2020 color space to the display
• be just used to the oversaturated colors you get with the display in SDR mode

Why does my screen block the brightness control in HDR mode but not contrast?

Because displays are stupid, don’t assume there’s always a logical reason behind what display manufacturers do. Mine only blocks the brightness setting through DDC/CI, but not through the monitor OSD…

Why is my average emission capped at 270nits, that seems ridiculously low even for normal SDR screens as comparison

OLED simply gets very hot when you make it bright over the whole area, the display technology is inherently limited when it comes to high brightness on big displays

Writing graphics code in a unified model is quite a bit different from the conventional x86 model.

It isn’t. The difference is pretty small, and it’s just optimizations for when copies can be skipped and not a radical change in the approach of how rendering is done.

Intel would need their own equivalent to Metal if they wanted to do a similar move.

Not at all. If big-ish changes were required, they could be exposed as Vulkan extensions.

I don’t know enough about Vulkan to say if it’s compatible with this kind of approach

Of course Vulkan, the graphics API used on all modern phones except Apple’s, supports using integrated graphics efficiently.