variance based adaptive sampling should be activated when "use local subdivs" is turned OFF

[sharktacos]

As I understand it, older scenes do not have the variance based adaptive sampling introduced in Vray 3.3 enabled, and this must be done with a mel command: setAttr vraySettings.dmcAdaptiveMethod 1;

I would like to propose that If "use local subdivs" is left to be "ON" for older scenes, the vraySettings.dmcAdaptiveMethod will remain off for legacy purposes.
However, if "use local subdivs" is turned OFF in the scene this should automatically trigger the vraySettings.dmcAdaptiveMethod to be ON. After all, no one wants to have "use local subdivs" OFF and have the variance based adaptive sampling not work since that misses the whole point of this functionality.

[yolov]

There's more than just the case of local subdivs that needs the variance based method. That's why we haven't set a specific trigger. However, using the old method still allows you to keep "use local subdivs" to off (or on for that matter). The only thing that we did put in place was to keep rendering old scenes with the old method and render new scenes with the new method, unless vray is otherwise instructed with the above mentioned command.
We do have something in mind, though, so we'll definitely try and make this a bit smarter.

[sharktacos]

"There's more than just the case of local subdivs that needs the variance based method. That's why we haven't set a specific trigger."

My point is that no one would ever want "use local subdivs" OFF and not want the variance based method, which is why I'm suggesting the trigger. Can you think of an exception to this?

[yolov]

An exception would be rendering old scenes where the variance method would yield a different result and break rendering consistency, but that was something we were concerned with at around 3.3 and 3.4. A lot of time has passed since 3.3, though and yes, I agree that there's more merit to place triggers here and there, the use local subdivs included, to have it enabled in such cases. Like I said, we already plan to have it auto-enabled for some settings or combination of settings.

[sharktacos]

"An exception would be rendering old scenes where the variance method would yield a different result and break rendering consistency"

Right, but in an old scene the variance method would be off and "use local subdivs" would be on. So there would be no problem with rendering consistency.

It's only the case where someone opens an old scene and then opts to turn "use local subdivs" off. That's when the variance method would be triggered on since this is clearly the desire of the person setting "use local subdivs" to off.

[yolov]

Yes, I agree. We'll probably do more about this in the near future.

[sharktacos]

thanks Alex