V-Ray Light - Transparency

[JonasNöll]

Hi,

Corona and Octane (and probably other engines) offer the option that light can become transparent. But in V-Ray there is no such easy option AFAIK.
The workaround that I use is to create an additional plane with a LgtMaterial and map the same ramp inside and then disable the reflection for the VRayLight.
But I think in V-Ray 5 that anyway doesn't work anymore because can only disable specular and reflection together and not seperately, as far as I know.
Also lightlinking and so on doesn't really work conveniently like this and in general it has many disadvantages and makes a whole scene with many lights really annoying to work with.
Anyway this workaround is kind of annoying. In Corona or Octane its just an additional option in the Light itself. Or is there any option that I am missing in V-Ray?
Basically I just want to have this:


This is with V-Ray Light and gradient. No option to make light transparent, cuts over the other environment reflections.


This is with the annoying workaround. I would like to have a button to just make the VRay Light behave like this.

[matanov]

VRayLight respects the alpha of the assigned texture.

[JonasNöll]

Wow, it never occured to me to try that!!! Thanks for pointing that out, this solves so many headaches for me.
Maybe I was the only one, but I was always looking for an option in the light itself. In Corona and Octane the light itself can turn on or off this option.

[fixeighted]

Nope, not only you Jonas. LOL

Something for the docs I think

[matanov]

Something for the docs I think

Added

https://docs.chaosgroup.com/display/...-+Sphere+Light

[fixeighted]

Oh...cool...as simple as that
Thanks.

[JonasNöll]

Ok cool Alternatively a checkbox in the light itself would be where probably many would look for intuitively coming from other render engines.

In Corona the option is called "Occlude other lights", in Octane there was also an option in the light but I can't recall the name.
It was only after checking other render engines I found they have this easy option in the light and then was frustrated that V-Ray didn't seem to offer this. But I just checked back in 3.6 it worked like this already for years. Now I'm better not trying to think how many scenes I could have simplified and hours of time saved with this knowledge in the last years

[matanov]

"Occlude other lights" is doing something else and you will need it if there is another light behind the invisible one. It is coming to V-Ray as well in some of the next updates.

[JonasNöll]

Oh, that's interesting what is exactly the difference? Because to me it seems to be doing exactly what I was mentioning in the beginning, so just curious:

[matanov]

Add a reflective plane and check the light there

edit: this is the problem it will solve in V-Ray - there is a dome light and а rect light, if you make the rect invisible, you can see the dome "passes" through. When the "Occlude other lights" is implemented, you'll be able to keep that reflection intact.

[JonasNöll]

Oh alright, got it thx for the explanation!
In Corona btw the light doesn't become transparent when enabling the Alpha from RGB Intensity like in V-Ray, so if not through this then I wonder what would be the official method there then if it's not Oclude other Lights.

[joconnell]

I've to check this in vray 5 but in vray next, I don't think that vray lights that are set to use layer properties instead of object properties in max don't respect "visible to camera" / primary rays off - if the layer that they're on is turned off to primary visiblity the shape of the lights will still render. We often want to have the light visible but when we break things up into layers we rely on layer visibilty to hide / unhide. This is in vray next 3.3 for ref, I'll give it a run in vray 5 too!