Automatic Render Region? Possible?

[LFedit]

Hey everyone, I posted this topic here viewtopic.php?f=30&t=63447

It is basically just saying that we can only render one render layer at a time. But I have another question since this is the case.

When I render something on its own render layer, Lets say a ball in the scene and the camera pans past that ball or something. I get way faster render times when I use render region on that object. So what I do is animate the render region to follow that ball going across the screen. Would it ever be possible to do like an automated version of this? I am by no means a programmer, so I don't know the correct terminology or anything like that, but is there any way to calculate like a matte of that render layer, then automatically tell the engine to create a render region like 5 pixels outside of that render layer? So then I don't have to animate the render region by hand but still get the benefits of using it.

Just an idea trying to speed up workflow.

Thanks!

[niestudio]

I had a need for such a solution recently too.
I haven't tried to build this solution, but I did give it some thought.
Seems like with some simple geometry and xpresso, a solution could be created.

Thought of parenting a single polygon to the sphere, set a look at camera tag on the polygon, scale it to the right proportions needed to visually cover all of your rendered geometry.
Setup xpresso to measure the percentages of the screen the polygon it using and transfer those values to the render region.

I don't know enough about xpresso yet, but perhaps someone else knows if this might work.

[LFedit]

Ahh I get what you are saying... Makes sense. At least its some type of a solution. The pixels on the render layer have to have some type of position on a grid too. Has to be someway to do an offset of them on like x +, x- etc..

But yeah, beyond my knowledge as well...

[indi_80]

It willbe nice if we can add manualy noise treshold for adaptive sampling (or somekinde multiplayer) for object or material - maybe in octane object tag. Then we can easly use this as custom render region
I had exterior scene where i had big asphalt parking and it was looking ok quaite quickly but adaptive sampling seen it as noisy becouse of grainy texture, bump, specular etc