[BUG] VFB region render in progressive mode does not work

[Dart_Design]

Hello Chaos Team,

Just found that region render does not work in progressive mode at all. To reproduce the issue :
1. just use default settings
2. start rendering
3. set region render somewhere and you see that it has no impact at desired zone at all... ("follow mouse" woks ok)

I am using latest Vray version
Please look at the image attached.

Thanks

[M.Max]

I don't think changing region ever worked for final rendering, but only for IPR and that's reasonable.
If you want to render only a region then set it before starting the render and not after.

[vladimir_krastev]

Hi if you are using production rendering as M.Max suggested then the region will not work after you have pressed the start rendering button.
If you are using IPR then every time you change the region in size or position the rendering will refresh and re-calculate for the new region.

[Dart_Design]

Hi if you are using production rendering as M.Max suggested then the region will not work after you have pressed the start rendering button.
If you are using IPR then every time you change the region in size or position the rendering will refresh and re-calculate for the new region.

Thanks for the answer.
Please can you tell me, why follow mouse mode is still working and region render mode not and what I need to do If I see for example that some corner or object is still noisy for me and I do not want to refine the whole image anymore, but desired zone/object only?

[vladimir_krastev]

Hi if you think that an object in the scene is still noisy you can use the render mask in "selected" mode, select the object and render again. V-Ray will render only the selected object. There are other modes as well like layer, include/exclude list, etc.



Another way to do this is rendering a region and your own mask (for instance cryptomatte). You can compose your final image using the mask and rendered region in post production.

[^Lele^]

Thanks for the answer.
Please can you tell me, why follow mouse mode is still working and region render mode not and what I need to do If I see for example that some corner or object is still noisy for me and I do not want to refine the whole image anymore, but desired zone/object only?

That is taken care of by the adaptive sampler: you just need to set a higher Noise Threshold (so the rest won't keep sampling), and wait.
Fiddling with region render, masking and mouse follow will only lead to uneven noise across the image, which will be then difficult or impossible to clean: that's why there's more of that allowed for IPR (which doesn't produce a final render) than for offline (which needs to ensure final production-grade quality.)

[Dart_Design]

vladimir_krastev @lele

Thanks for your replies. I have reported this because in progressive mode (not IPR) the main difference between “follow mouse” mode and “region render” mode for end user is only the form of action.
Follow mouse has circular zone (seems like even with falloff transition) and region mode has rectangular zone. Circular works and rectangular not. Sorry, but I still don’t get it Why “following mouse” still works then? Is adaptive sampler working different for follow mouse mode?

Masks are good for sure, but this requires more extra steps, which are simply too much for most of the cases like simple archiviz rendering, where you do not want to re-render something, but want for example to have more clean corner in the room.

As for me, having dynamic region render option is always time saver, at least the user has an option to use the masking or regions.
Please, look how easily it can be (the video is from 2016):
https://www.youtube.com/watch?v=GVGDeVL4u0w

And I think many users which have tried corona can confirm this.

Anyhow corona made this and it works great.
Of course, we can simply wait ... But even for AI lookdev previews this is a good option to have when overall image is already smooth and looks okay, but some areas are still with artifacts because of high noise level on specific areas..

It would be nice if the end user can choose the desired option, because in most of the cases it is enough to use simple render region. I say this because of experience from corona renderer, where I rarely touch any masks to refine the renders for daily arch viz projects.

[^Lele^]

Why “following mouse” still works then? Is adaptive sampler working different for follow mouse mode?

Indeed, as mouse follow still samples the whole image for noise threshold, and as the part under the cursor (assuming you left it somewhere and didn't move it.) reaches the N.T, it will start sampling the rest of the image to bring it within the set N.T.
That's quite different from marrying noise levels between old and new render regions.

That Corona does it is unfortunately not a good heuristic as to the practicality of implementing it for our engine.

[Dart_Design]

lele

Thanks for the Information, that's good to know. Is this Info present on Vray Help docks ? I am not 100% sure, but it sounds completely new to me.

This mean that we have a proper refining tool for Progressive, but only in circular mode. Is it possible to somehow control the radius for following mouse in progressive mode?
Right now we have a lot of cosmetic options for region render in VFB settings, but none for following mouse... I really hope that region render mode will simply work as following mouse for progressive, because it is not only the missing function, but also logical ... (otherwise it must be completely greyed out when progressive is running)

[^Lele^]

Is it possible to somehow control the radius for following mouse in progressive mode?

With V-Ray as renderer type

renderers.current.progressive_track_radius = 30

in the maxscript listener and press the keypad enter key at the end of the line.
30 is the default value.
This resets to default each time the render settings are different from when it was set (i.e. reset, new scene loaded.), but it will save with the scene it's been set to.

[Dart_Design]

lele

Thanks for the info.

UPD: In bucket mode we have the same story. Region render function is active, you can draw rectangle (sadly,only one), but it has zero function if the rendering is started. The buckets priority are always only on the "follow mouse" side. It will be great if we can draw region/s as priority zone also. Possibly, with the combination of region and following mouse mode. For example - you draw some rectangle as limit zone and then you can give another priority via follow mouse mode to set where exactly you want to start. Otherwise you can not use "follow mouse" as future patch for existing render, only like lookdev mode here and now. (rectangular patches are a lot more comfortable to replace)

Is it possible to fix this, can you please log this request in the system ?