Attenuation on V-Ray lights.

[rmaytee1]

I often, I mean very often have a square light fixture where a V-ray light would be ideal, but you have no control on how far away the lighting will fade. You're just stuck adjusting the intensity. This is typical for up/down wall washing lights. I always end up just using a standard light, so I can control the light fading off. It would be nice to use V-ray lights instead though.

[3LP]

do you mean that you want to be able to choose the "directional" angle of the light ?
If it's that, I second that
I already had the problem of putting some vraylights and had to put some "caches" on the sides of the lights because I would like a directional light.

Vlado could we have something like the "hotspot/Beam" parameter that is in the standard light?

[deneb26]

naa, i think he wants an option for the vraylight to set the initial light-fading-distance, which is unnatural though.

ale

[duke2]

I'm pretty sure the attenuation/decay is based on the inverse sq of the light area. I don't really know how you'd do a multiplier for this, however being able to control how much the light affects the area around it while keeping the same intensity and light size would be useful.

[jonahhawk]

you can affect this somewhat with the Cutoff. but if you're not careful, it can be a sharp cut.

[cecofuli]

you can affect this somewhat with the Cutoff. but if you're not careful, it can be a sharp cut.

I think in the next release, this problem is correct with a blur cut. Maybe in a custom blur cut? I hope

[Morbid Angel]

I also asked for this option many times. Yes its not correct, but cheating to make things look good is part of the job. In mental ray there is a number of light shaders which has falloff start/end points, which I think can be very useful in some cases.

[soulburn3d]

I know this is a really old thread, but would love to see this too. The distance from light based attenuation would work on top of the current inverse square falloff, so you can use it to simply blend the light off earlier than the falloff does naturally, or turn it off to use the default and physically correct inverse square falloff. Its a useful cheat when you just want to cut the light off and limit it to a specific area.

- Neil

[vlado]

I think we'll skip that. What we will probably add, is the ability to use a mask texture for the lighting, which simply modulates the light intensity depending on the texture. Then you could use a Falloff map in distance mode, or a VRayDistance texture to do all kinds of fun stuff. This should be much more flexible than a mere attenuation.

Best regards,
Vlado

[soulburn3d]

While it would be more flexible, having the gizmos in the scene showing specifically where the near and far attenuation reach in 3d space is super useful. With something like a falloff map, you have to adjust numbers, test render, adjust the numbers again, test render again, which causes a lot of iterations to get the correct value.

- Neil

[vlado]

Which is why you have V-Ray RT

Best regards,
Vlado

[soulburn3d]

Which I can't use because its not compatible with enough 3dsmax features yet

- Neil

[soulburn3d]

BTW, I apologize if my last message came off as too snarky. I would love to use VrayRT in production, but since it is still not compatible with a number of key max features/plugins, I am unable to use it, hence why things like viewport gizmos are still important.

- Neil

[Neilg]

you don't have to completely switch over to it. Most projects i work on I have a separate scene for merging materials and lights into which is set up to use rt. I'll have a basic shell of the scene and work in that for a while on a material or light, save selected, merge back into the render scene for final render. keeps things nice & tidy (and light on rt!) and you dont need to piss around with preview settings in a near final scene.

using falloffs in a light sounds fun

[soulburn3d]

you don't have to completely switch over to it. Most projects i work on I have a separate scene for merging materials and lights into which is set up to use rt. I'll have a basic shell of the scene and work in that for a while on a material or light, save selected, merge back into the render scene for final render. keeps things nice & tidy (and light on rt!) and you dont need to piss around with preview settings in a near final scene.

While that is a workaround, that sounds way overly complex to me. I think I'll just stick with lots and lots of render regions, and will join everyone in the realtime world when it gets more feature compatibility.

- Neil