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tburbage
10-02-2018, 11:50 PM
If I change a light color via the Properties panel, then jump into the Node Editor via the light's Edit Nodes button, add a LightInfo node to the graph and set its Light input to that same light, I don't see any relationship between the color I chose in the Properties panel and the Light Info's Color output.

Am I misinterpreting what LightInfo.Color represents? It's strange because if I also change the light's Shadow Color, that value *is* reflected in the LightInfo's ShadowColor output...

MonroePoteet
10-03-2018, 08:40 AM
This works for me in LW2018.0.6:

142978

mTp

jeric_synergy
10-03-2018, 09:49 AM
Works here. (2018.0.6)

What color IS the node reporting?

Kryslin
10-03-2018, 01:20 PM
One thing I noticed, is that the color being reported is actually color * intensity. Divide the light color by it's intensity, and you should have the color you set, in the range of 0...1.

jwiede
10-03-2018, 03:21 PM
One thing I noticed, is that the color being reported is actually color * intensity. Divide the light color by it's intensity, and you should have the color you set, in the range of 0...1.

Hmm, as they also provide a separate "intensity" output, that seems like it might be a bug -- it makes obtaining normalized color channel values really inefficient (3x fp division not incl. nodal overhead).

tburbage
10-03-2018, 07:34 PM
One thing I noticed, is that the color being reported is actually color * intensity. Divide the light color by it's intensity, and you should have the color you set, in the range of 0...1.

You're right! If I set the Light's Intensity to 1.0 lx, the component values look like what I was expecting/match the Properties panel's Light Color component values. Given that the node provides the Intensity value as an output (as Jon pointed out), why would it not report an "unmultiplied" value for Color? Maybe that's technically correct in a PBR world?

Tobian
10-04-2018, 06:27 AM
I believe that the light colour and intensity acts as a multiplier to the inputs, so for example with the environment light, if you sample the environment, it is untainted, but if you vary the base colour, that will act as a multiplier for tinting purposes, and the same with the intensity. If you're using the nodal inputs, the base colour and intensity multiply with whatever you're feeding into the node input, unlike the surfacing system, where you replace the surface with another, you're just tinting the light with those inputs.