Frame Buffer Question

[Danielhruby]

I'm used to being able to are-render cropped areas of the render window to patch in fixes. It seems in the VRay Frame Buffer, starting a render region will render the patch, but the previous full image render is overwritten. So, rather than patching the region into the previous image, I think I would now have to composite the two images in PS or somehting. Is there a way to make this work?

A related question, is it possible to add a method of creating Render Regions based on material. So, that only the pixels that show the chosen material are masked as a collection of Render Region pixels. May not be possible, but one can dream. Thanks guys. Loving VRay so far!

[vladimir.nedev]

I'm used to being able to are-render cropped areas of the render window to patch in fixes. It seems in the VRay Frame Buffer, starting a render region will render the patch, but the previous full image render is overwritten. So, rather than patching the region into the previous image, I think I would now have to composite the two images in PS or somehting. Is there a way to make this work?

This shouldn't happen, the render region should be rendered on top of the image already in the VFB.
The existing image is cleared ONLY if the resolution changes.
My guess is that you were using RT to render the initial image and then switched to production rendering, or resized the VFB window.
In RT, by default, the resolution is scaled to fit inside the client area of the VFB.
You can disable this by unchecking the toggle button shown in the attached screen-shot.

A related question, is it possible to add a method of creating Render Regions based on material. So, that only the pixels that show the chosen material are masked as a collection of Render Region pixels. May not be possible, but one can dream. Thanks guys. Loving VRay so far!

We have the render mask feature, which is basically a render region with shape based on one of
- item selection
- external image
- connected items
- list of object IDs
Internally this feature doesn't support masking based on materials, but we have it logged as a feature request.
You might still find masking based on items more useful than the rectangular render region.

Greetings,
Vladimir Nedev

[Danielhruby]

Wow! Cool. Nice to know there is render masks. I will play around with it.

[Danielhruby]

This shouldn't happen, the render region should be rendered on top of the image already in the VFB.
The existing image is cleared ONLY if the resolution changes.

I did some more tests. Rendered with Production render, set a render region to repair a bad material, rendered again, and the original image gets covered in black leaving only the rendered region. I cant save out a fixed image, I have to save out the new patch image and merge in photoshop and delete black area. Ideally, I should be able to renege patches all over my final image and then be able to save out the final image. I made sure that I didnt render anything or change to RT before a second Production patch render.

[vladimir.nedev]

This is not what's happening for me on a simple scene.
You will have to give me a scene that reproduces this behavior and/or record a short clip that demonstrates how it happens.
Here is what happens here : https://youtu.be/0WCpwgCcclg

Greetingsm
Vladimir Nedev

[Danielhruby]

Vlad,

I figured out that I needed to refresh the final render by either by Update Effect or by clicking on the final image to make the black mask outside the region area disappear. So, now I know. Before that, I was using the RT in between Production takes. Thanks!

[Danielhruby]

This is not what's happening for me on a simple scene.
You will have to give me a scene that reproduces this behavior and/or record a short clip that demonstrates how it happens.
Here is what happens here : https://youtu.be/0WCpwgCcclg

Greetingsm
Vladimir Nedev

Vlad, It happened again and it is now clear to me that the RGB + Effects that will not refresh the entire image outside of the render region. All other render elements update as expected, but if you are using bloom/glare + render region, then you have to either re-render the full image or do the photoshop composite approach to get the image fully updated.