Is there a way to tell Vray to hold on to what it has already exported for renders?

[GidPDX]

I'm just doing some render region tests on a project that has a lot of elements to it, and am only adjusting sampling settings for Vray etc., but each time I go to render a region in the VFB, it has to load the whole scene again.

Seems a waste of time if none of the shading or geometry has changed. Is there a way to have Vray hold on to what's loaded so I don't have to wait each time for it to load the scene again while doing these tests?

Also, RT at least seems to load everything in a scene. Even if I hide all but one object, it's still wanting to render everything. Is this a known issue? Do I have to set my items to not render vs. just hide them? For MODO's preview we can just hide things and they will not show up.

[vladimir.nedev]

I'm just doing some render region tests on a project that has a lot of elements to it, and am only adjusting sampling settings for Vray etc., but each time I go to render a region in the VFB, it has to load the whole scene again.

Seems a waste of time if none of the shading or geometry has changed. Is there a way to have Vray hold on to what's loaded so I don't have to wait each time for it to load the scene again while doing these tests?

We could improve this, yes.
V-Ray for MODO could store a cache of the scene's geometry, so it doesn't have to be fetched each time you re-render the same scene.
It will take additional RAM.
Also, we have to figure out how to update the cache.
If we do it automatically, there is always the risk that some change is not detected and the geometry is left in its old state.
So, we have to provide a manual reset of the cache as well.

Also, RT at least seems to load everything in a scene. Even if I hide all but one object, it's still wanting to render everything. Is this a known issue? Do I have to set my items to not render vs. just hide them? For MODO's preview we can just hide things and they will not show up.

If you are hiding the items from the View menu commands (shortcut 'H'), this won't work.
The MODO API doesn't provide access to this state for items. For polygons it should work.
You can bring it up to The Foundry developers.

I added the "Render only selected geometry" option mostly because of this.
You can enable it (the 'S' icon in the V-Ray tool-bar) and then only your selected item(s) will render.
This provides workflow similar to using the View menu hiding.

Or you can hide items using their "eye" icon.

Greetings,
Vladimir Nedev

[GidPDX]

I'd be fine with it using more RAM and having to manually reset for now. It would be a work flow improvement over what is happening currently TBH.

Ha- I guess I need to review the UI once again! Using the "S" to show selected might work for this instance- good to know about "H" key not working.

Too bad about the MODO API on this. I'll send an ER to the foundry on it as I'm sure other developers would like to have this enabled too.

Thanks Vladimir- you guys rock!

[GidPDX]

Does using S to only render selected only work with RT? If so can we get it to work with the standard render too maybe, at least for the VFB?