For my exterior visualisations I'm trying to develop a lighting system which allows me to randomize the colors of groups of lamps, instead of all lamps individually.
The practical application of this would be to be able to put several lamps in the larger rooms while keeping all lights in one room in the same color, but still being able to randomize the colors of individual rooms
What I've tried so far is to use Object ID's to drive the randomization. After several tests I came up with a ridiculously simple node setup which the trick, with an Object Index input going through a White Noise Texture for the randomization and into a Color Ramp node. As you can see the cubes below are all individual objects which share the same material. The only thing making the difference is that each group has a different Pass index assigned to its objects. Of course the same result can also be achieved by using the Random input and joining the groups together, but..
My problem is that I'd like to get the same result using point lights (because I believe those create less noise?). However, due to the way Lamps work in Blender I can't seem to get the Object Index input to work. The Random Input works fine though, but I still want to get those groups. I've been trying this for hours to get it to work with copies of the Lamps with different ID's and duplicates with different ID's but no cigar. The way these lamps share data is a big obstacle for me, I guess the key might be found in NodeGroups to share settings between copies, but no luck so far.
Any ideas or solutions will be much appreciated!
