Add some more hardware DDC control options

[waydabber]

Some of these adjustments are supported by various displays. Should be in a submenu much like color controls as a Pro feature.

• [ ] Contrast control
• [ ] R/G/B Hue
• [ ] R/G/B Saturation
• [ ] R/G/B Gain

[dave-epstein]

Any idea when this might come out? Having a contrast control (esp. with a keyboard shortcut) would be great. Would it be pleasible technically to support this on DisplayLink screens too?

[waydabber]

Hi @dave-epstein - everything is ready in the app to implement these so I think I'll add them soon.

DisplayLink control is unfortunately not possible at the moment as these displays simply act like virtual displays in the OS and there is no way to perform the access the i2c communication channel to the display required for DDC.

Maybe I should contact the maker of DisplayLink to see if they can offer some way through their driver to enable DDC control.

[roelvangils]

Not having a contrast slider is the only reason I keep your other app MonitorControl open as well ;)

[waydabber]

Oh yes, sorry, I'll work on this, just stuck with other life matters. It's on the roadmap! :)

[roelvangils]

Don't feel rushed at all! :)

[dotsam]

The latest DisplayLink release has beta support for f.lux https://support.displaylink.com/knowledgebase/articles/1990237 which I would think might more generally be support for color table manipulation?

There was no flux update to correspond with this, so my thought is that this might work through an existing system API now?

[waydabber]

I don't think it uses the system api but probably a direct cooperation with f.lux? But I can provide a build that allows color table manipulation for non-dummy virtual displays to see if anything happens.

But if there is a demand, I could contact DisplayLink and ask about a custom way to have DDC and colortable manipulation support. Surely they have the ability to implement these things as the hardware is capable (it is available in Windows) and if they provide an API for it (and have some test kit), I can implement whatever is needed in the app.

[dotsam]

I did a bit of poking around in f.lux with Hopper and didn't see anything DisplayLink specific, but I'm by no means an expert in disassembling.

Regardless, I'd be happy to test a build that attempts color table manipulation on virtual displays.

[waydabber]

Sure, here is a build that reports virtual displays as colortable manipulation capable but uses the standard macOS APIs for it. Let me know if something is changed with the latest DisplayLink beta drivers. Thanks!

BetterDisplay-v1.3.0-alpha1.zip

[dotsam]

This seems to work exactly as it should with the DisplayLink 1.7 drivers and the Allow f.lux to warm colors at night option enabled.

Brightness/contrast/RGB/color temperature all seem to work. The only issue I've noted is "distorted" colours when pushing contrast or gain too high into the positive.

The other item of note is that when color table manipulation is enabled for a display, but the DisplayLink f.lux option is disabled, no adjustments actually happen, including brightness. I'm don't know if there's any way for you to tell when this is the case, but if you do make this an option in a future release, some explanatory text would probably be a good idea. Presumably this feature in the DisplayLink software will go out of beta at some point and will be enabled by default though?

[waydabber]

This is great news, thanks for testing it! I’ll add a new "Force-enable colortable manipulation" option to virtual displays with some explanation regarding DisplayLink v1.7 driver requirement and Allow f.lux to warm colors at night to be enabled.

[waydabber]

https://github.com/waydabber/BetterDisplay/issues/750

[waydabber]

I'll make the contrast control hidden by default.

[waydabber]

Added keyboard shortcuts as well:

There is an added option under the display to change whether the main slider and keyboard control should prefer hardware or software contrast control (if available):