I wrote this simple but cool rule that syncs one lamp's color to another and thought I should share it. It uses built in features of rule machine so nothing required other than the built in features.
I'm sure there is a built-in app called mirror which does the same thing.
I can see how you're not using the state - so a mirror app wouldn't technically apply. Still, I always scratch my head about sync or mirror - isn't that what a group is basically?
No, Mirror allows you to use a "real" device to mirror to some other real (or virtual, I suppose) device, the intent being to make remote control-type devices that internally track switch state, level, color, etc. easy to use to control a real device. Otherwise, you'd be stuck writing a bunch of rules or figuring out some combination of apps to do the same.
If you only need some effectively "virtual" control device, then Groups or Room Lighting can certainly handle that with the activator, yes.
I had no idea - well my little hack works perfectly fine. In the end I ditched it and instead am using a rule in my own HousePanel app to sync my light colors, mainly because I can and it feels cool to use something I wrote. Here's a screen grab of my rule as it is defined in HousePanel:
You need to turn this into a user app so it can be shared! That's a useful tool for those of us that have CT in our environs. Wish I'd thought of it!
Look at my garden hue app if you want lights to color change in sync.
It already is a User app, and it is available for anyone to use. The latest version is in the "hpsql" branch on my github repo here:
The discussion thread on this forum can be found here: HousePanel 2 Node Version - #102 by kewashi
Once upon a time HousePanel had a decent following and was actively discussed. It has evolved over time with not many users other than me, but I personally love it. The graphical editor, tile customizer, and built-in rule engines are the features I love the most.