A couple of regressions I noticed with Vray 5 Update 2

[Alex_M]

Hi,

I've just installed the new update eager to check it out and I really like the new features and improvements. Especially the addition of thin-walled refraction for GPU and the QT UI improvements!
Unfortunately, I noticed some regressions as well compared to the previous version I was using - Vray nightly 5.10.04 build 30874. I've made a short list:

1. IPR starts rendering from scratch every time I draw a region render on top of an already rendered portion of the image when using Light cache as the GI engine. This is a regression from the older version I was using where this did not happen.
2. Undersampling seems to be broken. It does almost nothing to improve IPR interactivity for me, even when using Brute force for GI engine. If anything, it's worse having it enabled since the preview is blockier. IPR was massively more interactive when having it enabled with Brute Force as a GI engine in 5.10.04 nightly build 30874.
3. I'm not sure about this one and it might probably be intentional and a necessary change, but I noticed that Light cache seems to get calculated more than once for each IPR refresh whereas in the older nightly build I was using it was more seamless and the image appeared almost immediately without weird flashing.

[matanov]

Hi Alex,

1. In the previous version (5.1), LC was calculated only at the start of the IPR session only for the current image window and then rendering for new regions used that initial LC. This is why the "resuming" rendering effect was possible. This approach however has its problems - f.e. if you start with a region (not the whole image) you'll have only the LC data for that piece of the image, which means that the moment you move the region somewhere else - rendering will be without LC data, thus being wrong (different GI). It will get worse if you change something drastic in the scene within the same IPR session. The new behaviour (always calculating LC) ensures correct rendering. I will talk with the GPU team about this to see if we can come up with a better solution for smoother experience.
2. We'll take a look.
3. Hm, can you show me? Maybe over email.

[Alex_M]

Hi Peter,
Thanks for the clarification. I'll try to capture some videos for points 2. and 3. with Update 2 and the older nightly I was using as soon as possible.

[marksmanguy]

Hi, this issue is happening again. Is there a nightly fix please? Thanks

[matanov]

Hi, this issue is happening again. Is there a nightly fix please? Thanks

Which issue? #1 is not an issue (as described in my previous post), #2 has been addressed in the latest official version (5.2.2) and for #3 I'll need an example scene.