I can successfully set the rgb_color values from node-red using the call-service node
I set Data to : {“rgb_color”: [100,10,30]}
The State in HA for the virtual light entity shows this as a result:
rgb_color:
- 255
- 25
- 76
What is happening is the highest number specified in the call-service node rgb_color data (100 in my example) is set to 255, the other numbers are set proportionally to that highest number.
so with [100,10,30] I get:
100=255 (highest number so it gets 255)
10=25 (10 is 10% of 100, so 10% of 255 is 25)
30=76 (30 is 30% of 100, so 30% of 255 = 76)
The brightness value has no effect on the ratios and final numbers.