Render region with render elements

[OPEN_RANGE]

I'm unsure of how render region for small improvements affects the workflow of useing render elements.

Using vray frame buffer and using render elements, including denoiser, will using render region to update a small area of frame buffer also update the render elements?

Would it make a difference if render elements are saved as separate files vrsus included in a multi-channel .exr file or vrimage file?

Or might it be neccesary to save the Image from the frame buffer as multi-channel .exr?

[Svetlozar Draganov]

Render region is no much different than rendering entire image, all Render Elements will be updated including denoiser and etc.

There will be no difference for the Render Elements if they are saved into a single or multiple files or .vrimg, this is usually personal preference. One might prefer to work with single files another might consider single files as too heavy and prefer to operate with separate ones. Its important to know however that Denoiser Elements will be exported only to multichannel .exr or .vrimg files, they will be lost if you export to separate files.

[OPEN_RANGE]

Thank you for your helpful reply. That saves me experimenting with the various choices.

his thread, post #11 is what got me thinking about this:
https://forums.chaosgroup.com/forum/...c/76541-proexr

It appears to say that one cannot load a multi-channel .exr into the vfb. Only a .vrimg. Then goes on to say that one might choose to do that in order to render a small region for adjustment.

thanks again for your ongoing and excellent support!

[yolov]

Loading multichannel exrs into the VFB is not supported - they will load as single channel images (well, with the alpha, of course).
The suggested workflow in the thread you linked is a clever way to cheat when doing small changes on large-res images. For example, if you needed to do a small tweak on your scene that would otherwise require re-rendering the whole image. Instead, you can load in a vrimg into the VFB - it will come in with all the render elements (unlike exr). Given that you're rendering the same still image with the same vray settings from the same camera position and so on... do a region render on the portion of the image where your scene changed (say a new object is added or something similar that doesn't affect the entire image's reflections, GI etc so the edit looks seamless) - then you save out the image directly from the VFB - it will write to disk your rendered region, surrounded by the all the pixels from the vrimg that you loaded to VFB before that and containing all the render elements (sort of on-the-spot render-slash-comp).

[OPEN_RANGE]

Alex, that is very helpful to me.thank you!

[neilcooper33]

Hi all,

So now when i load in an EXR into the Vr frame buffer all channels appear, this must've been a software update.
But if i do a region render to fix the bit which has been updated, the rest of the render (outside the region) goes black. So my workaround is to load in the exr, save as vrimg, then do the region render, then save out as exr again....

is there a way i can do this and avoid the vrimg process?

thanks

Neil

[neilcooper33]

scratch that, it hasn't saved out the wire color for some reason....

[yolov]

There's been some changes along the way that might have changed something.
What V-Ray version are you using?