Material overrides don't work on VRayLightMtl with Direct Illumination enabled

[dgruwier]

I have a setup where I'm lighting my scene with an HDR projected on some geometry, using a VRayLightMtl set to direct illumination.
I need to blur the texture because otherwise it renders very, very slow. But I also want to keep the reflections nice and sharp, so I figured I'd just do a material override with a non-blurred texture for reflections. Looks like that's not an option, overrides don't seem to work with VRayLightMtl when using Direct Illum. Disabling direct illumination makes the reflection override work, but causes a bunch of other problems, so I want to avoid that. Is there another way to do this?

[shaio]

Hi,
sorry for the delayer answer. Which Maya and V-Ray versions do you use?
The reason why the override doesn't work with Direct Illumination ON is because in that case we export the light as "LIghtMesh" which is equivalent to assigning "Mesh Light properties" to the object. That is the reason why the override wont work. We should find why it renders so slow when the Direct Illumination is OFF since I tried with a 16k texture here and didn't have any slowdowns (V-Ray Next beta2). Is it possible to share a scene with the HDR in question so we could check the slow rendering?

[dgruwier]

I'm using nightly 28087, the last of the 3.6 ones. I opened it in Next (28439), and it looks like it's about the same, just a few seconds shaved off.

My next idea was to create two vrayLightMeshProperties, and make one visible to diffuse and the other to reflections. But it looks like it's locked to one mesh light per mesh. I suppose I'd have to duplicate the geometry..

It should be noted that I'm projecting the HDR onto a lidar scan of a large set, with lots of small lights and bright areas with grates in front of them, so I figured it's just a ton of detail to sample to get the noise down. I'll look into sending you a scene, but it's under NDA.

[shaio]

Since the scene is under NDA, please send it to support@chaosgroup.com with a link to this thread. They will provide you with the needed details if the scene is to big for sending over mail.
Thank you!

[yolov]

You should be able to instance the geometry but have each instance assigned to separate meshLight properties.
Btw, if you could send a simple version of your scene where you just used dummy geometry/textures - it would be then easier for us to try and come up with a workaround that you can test on your actual project.