Hi all
Tried searching for this but can’t seem to find anything.
First off, I’m pretty new to openHAB, although I’ve it a few times but only recently thought of dive into it again.
Now I’m searching for a way to have, preferred in HABpanel, a way to enter the colour I want in RGB.
I imagine to have 3 inputs, one for each channel, and input a numerical value between 0-255.
Is this doable?
Welcome in the forum.
Almost everything is doable. Can you feel us more about your system and what you want to accomplish.
In your case I think you create a proxy colour item (Color ItemName) and link your output items with a rule. You can use the colour item in HabPanel and the rule will send it to the correct output.
Thank you very much 
The idea is to have an HABPanel as primary frontend and be able to control, brightness, whitebalance and color pretty minute.
So my first idea was to have a slider that was coupled with an input field. If the slider was moved the input field would follow and vice versa. So in the RGB case i would have a slider and an input box for the red channel so i could control the precise color in different rooms.
Is that doable? Maybe just with an precise slider that shows the number it’s on.
I just tried the ideas and I cant seem to separate the individual RGB channels.
Is there something I’m missing?
You probably want to review @ljsquare suggestion in another light (sic).
Put simple Number or Dimmer Items with sliders on your UI, one for each property.
Make a rule that runs when any of the simple Items receives command, and combines into the complex Color Item.
You’ll probably want the inverse rule too, that runs when the Color Item changes and populate the split element Item values so that they get reflected in your UI.