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KDE Plasma Widget for external monitor brightness adjustment

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51–60 of 65 posts

Re: KDE Plasma Widget for external monitor brightness adjustment

#51
post #35

Earlier quoted context omitted.

DDC is how monitors send EDID information about their capabilities to the computer. DDC/CI adds the ability for the computer to send commands to the monitor for things like brightness and color settings and input selection. So Windows obviously is using plain DDC to offer you the right set of resolution choices, but none of the DDC/CI functionality appears to be exposed to end users, making it effectively unsupported…

I thought it was supported by NVidia control panel since ages? P.S. Not a user of NVidia now, might be a fake memory.

I don't recall seeing anything like a monitor brightness slider in their control panel. And even if there was, it wouldn't be a reliable indicator of OS-level support for that functionality because the GPU vendor's control panel is the most likely piece of software to bypass the OS and control the display config through its own means.

Re: KDE Plasma Widget for external monitor brightness adjustment

#52
post #48

Earlier quoted context omitted.

random question for you: i have a sony oled display that auto-dims on low color change activity (this is impossible to disable - believe me, i've tried, even in the diagnostics menu). do you have any idea how this could possibly be circumvented? Thanks!

That is an ABL or Automatic Brightness Limiter and it’s one of the things that’s messing Lunar’s brightness Sync algorithm because the max brightness is constantly changing. It might be possible to disable from the monitor hidden service menu, if you can find a way to enter it. But it will also greatly decrease the lifespan of the diodes as OLEDs are not made to go so long with high brightness and heat. If the monito…

thanks for the info. i also tried in the hidden service menu, no dice.

psa to all others out there, just watch out for this feature in oleds if it's a dealbreaker. otherwise i love this display as a monitor. for me it's not that big of a deal for the price i paid.

btw even my studio monitor speakers do this with no ability to disable... seems like a trend in major electronics these days.

Re: KDE Plasma Widget for external monitor brightness adjustment

#55
post #4

Earlier quoted context omitted.

There is a plan to add DDC to the Linux kernel, so that any desktop can manage external monitors using the same APIs they use to manage internal laptop panels. Hopefully that would mitigate the problems you mention.

https://gitlab.com/ddcci-driver-linux/ddcci-driver-linux

Yeah. There was an attempt to upstream that driver (by someone not involved in it), and the need for a better userspace API for backlight control got mentioned, so the driver wasn't merged. Probably a better driver will get merged eventually.

https://lore.kernel.org/all/7f2d88de-60c5-e2ff-9b22-acba35cf...

Re: KDE Plasma Widget for external monitor brightness adjustment

#56

Earlier quoted context omitted.

https://gitlab.com/ddcci-driver-linux/ddcci-driver-linux

Using this driver, Powerdevil does not allow you to set values individually per monitor, instead gives you only a single slider. This is absolutely sufficient for single monitor or multi monitor setups with identical models, but in my case I need the option to set it individually since my monitors are all differently bright on 100%.

See my comment above, per-display brightness config will need changes to the Linux kernel brightness userspace API.

Re: KDE Plasma Widget for external monitor brightness adjustment

#57
post #22

If your distro doesn't have a package for the backend of this plasmoid yet, it invokes the backend with[1]: python3 -m ddcci_plasmoid_backend So you can probably get away with this: git clone https://github.com/davidhi7/ddcci-plasmoid \ && cd $(python3 -c "import site; print(site.getsitepackages()[0])") \ && ln -s $(cd -)/ddcci-plasmoid/backend/ddcci_plasmoid_backend . [1]: https://github.com/davidhi7/ddcci-plasmoid/…

Developer here, why wouldn't you just install the official pip package `ddcci-plasmoid-backend`?

I personally avoid using pip for managing system libraries because they often end up conflicting with distribution provided packages. Even if packages are missing upstream, they often pull in dependencies that may end up conflicting later. Versions start mismatching, tools stop using when sudo gets involved, all kinds of weirdness that's hard to debug if it's caused by a library you pulled in months ago.

My workaround for this problem is to install these tools in a separate venv and calling the binaries with their full path, but for tools like this where the command is built into the program that may be more difficult. It's also a waste of space in some cases, though deduplication tools can help there.

Re: KDE Plasma Widget for external monitor brightness adjustment

#58

Is Kde that outdated that it needs this?

I don't know of any mainstream OS/DE that integrates this natively. Laptop displays are almost universally supported by brightness controls but even Windows doesn't seem to come with a tool to control standalone monitor brightness.

Re: KDE Plasma Widget for external monitor brightness adjustment

#59
post #49
post #38

Earlier quoted context omitted.

There is also Clight ( https://github.com/FedeDP/Clight ) if you want automatic backlight adjusting given ambient brightness. It supports external monitors through ddcutil C library and has many more features to offer. Disclaimer: i am its creator ;)

I've tried setting up clight on various occasions and now gave it a shot again, whilst I appreciate all the documentation I'm still struggling to get it working on NixOS with swaywm on a laptop. I'm primarily interested in adjusting screen brightness based on my webcam. I'm already using redshift/gammastep.

Uh that's sad! There is actually an issue opened about NixOS; but, since I am not using it, it's pretty hard for me to debug. If you want some help you can comment on that issue though!
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