ambient light and light select

[frueter]

When attaching a VRayAmbientLight to a light select node the respective AOV renders black.
Is this a bug or by design (seeing ambient lights are a little naughty)?

[Christophe.Cot]

While it is clear the ambient light will not generate specular, you should see something from the diffuse part.
Here I see something when using direct illumination, raw or diffuse mode of the light select.
Can you describe your setup and parameters ?

[frueter]

Attached is my test script and a screen shot:

[Christophe.Cot]

When the light select uses direct diffuse, raw or illumination, you have something in the aov. The "full" mode provides indeed a black output.
Looking at the code of the ambient light plugin, it is expected. The same calculation is used to fill the illumination, raw and diffuse channel, while the full channel is not handled at all.
Maybe it should, but that's probably pointless since the full contribution is meant to add the indirect light contribution which in the case of an ambient light is 0.
So at the end the full light contribution would be again equal to what you see in the diffuse channel so you can just set the mode the direct diffuse instead.

[frueter]

Ah, I totally missed those settings in the LightSelect node. Thanks!