Velocity through glass, possible ?

[stilgarna]

Hello

is there a way to get velocity behind a refractive material ?

I want to avoid using 3D motion blur because of render time.

Best regards.

[vlado]

You could set the "Affect channels" option for your glass materials to "All channels", which will cause the glass to propagate the velocity channel, but it might still look weird.

Best regards,
Vlado

[stilgarna]

Thanks Vlado !

I'll make some tests.
Maybe I'll try mixing 2 different velocity results, one with the glass one with "all channels".

Best regards.

[stilgarna]

Hello Vlado,

here is my setup : max 2016 - vray 3.40.03 - 3dsmax physical cam
As you say I change the "affect channel" to all channels and I don't thinks it's works, or maybe I did something wrong...


This is the result with the glass:

Velocity



This is the result without the glass :

Velocity

[stilgarna]

The strangest think is that it's working with zDepth and only when it's filtered.

[vlado]

It needs to be filtered for the "Affect channels" option to work, but I'm not sure why the velocity is not propagated; we'll have to reproduce this here.

Best regards,
Vlado

[matanov]

It appears that it's a known old issue, will bump it the system.

[stilgarna]

It needs to be filtered for the "Affect channels" option to work, but I'm not sure why the velocity is not propagated; we'll have to reproduce this here.

Best regards,
Vlado

Here is my scene :

https://wetransfer.com/downloads/c0a...7104231/6b8a2e

[stilgarna]

Hello guys,

as it's sort of a bug

1) is there any chance to see a fix for vray 3.40 ? (I know you've got many others things to do at the moment)
2) is there anyway to get a velocity through glass in vray ? (maybe with the sampler info, but I don't see velocity vectors)

Hope you can do something for me !!

I've got two big technical project where I really need to avoid heavy stuff like Motion Blur 3D and Dof 3D, bug I've got glass (a watch animation/explanation project)

Best regards.

[stilgarna]

Pleeeeeaaaaasssseeee

[matanov]

Ok, I've raised the priority, but only because of the kitty!

There is no way for this fix to be in some future version of 3.4 (we are already on 3.5).

[stilgarna]

Ok, I've raised the priority, but only because of the kitty!

There is no way for this fix to be in some future version of 3.4 (we are already on 3.5).

Thanks !!! next time : more kitty !

[stilgarna]

Hello Guys !!!

I've just try the new 3.50.03 (max 2016) and velocity trough glass doesn't work



Pleeeaaaaaase !!!

PS: I add a test scene to this message

[stilgarna]

Any chance to see a fix ?

Best regards.