Tech question: Adaptive sampling?

[Chris_TC]

I was wondering whether it's possible to make an unbiased renderer sample adaptively, or does Octane do that already? Often times, there are only certain areas of an image that are noisy (e.g. the glass windows of a house while the environment is perfect already). So it would make sense for the engine to only keep calculating these areas of the image.

It works with adaptive anti-aliasing, which compares neighboring samples, and if they are below a certain threshold, no more sampling takes place.

If there is no automatic way of finding out which areas need more sampling, how about this crazy idea:
Let me "paint" areas into an image that's being rendered. This would tell the engine to only keep sampling those areas but leave all other areas the way they are.

And while we're at it: why do I have to render an image 3x the size and then downsample myself? There should be a button telling Octane to oversample internally by a specified factor.

[PolderAnimation]

Sounds like a good idea. Painting masks don't sound that good, a solution should be something that also works for rendering animations. But what about a option for each material, so you can adjust the amout of sampling for the window material.

Or a quick analising render to see how well the fotons are spread around the scene.

But if where bussy making stuff, I rather want this http://www.youtube.com/watch?v=Ee51bkOlbMw. (this is already posted a couple off times on this forum, but still I find it very interesting).

[colorlabs]

Isn't this what the PMC rendering option is for?

[matej]

Both ideas (adaptive AA & mask the user would paint) are good and useful. I hope something like this will be implemented along the way, cause it's a waste to sample areas that are already clean, instead of other areas that are still noisy like DOF, glass surfaces...