Blog: progressive importance sampling

[Ondra]

https://corona-renderer.com/blog/research-corner-progressive-importance-sampling/

[jjaz82]

wow .. congratulations for the excellent work..

Research is the vital point of these software

keep going :)

[blackice]

well done!
>B.

[maru]

Looking at things like this makes me think my school was such a huge waste of time and money. :(

[Avan]

Simple for understand, but it looks amazing ! Can we see the feature in bulds?

[crazyman]

Keymaster:

- Can you set custom amount pings or pongs will algorithm perform, before it start path tracing? Or is it predefined values defined by algorithm being used?
- How this affect animations? Does importons/photons calculated once for all frames while doing static animations?
- What if objects changing it's position/material properties while animated? Does algorithm need to calculate all pings-pongs for every frame?
- If so does it produce unwanted "pixel shimmering" ?

[Ondra]

the number of iterations is configurable. We ended with something like 30 batches of 1 million photons+importons each.

Animations, shimmering, etc. works exactly the same as other unbiased algorithms. We did not do cache sharing between frames, although it would be possible.

[juang3d]

So if I understood correctly, this won't flicker with animation, right? because you are not using photons to light, but to drive the paths, is this correct?

It seems to be a pretty good system.

Cheers.

[Ondra]

It would not flicker, but it would shimmer

[crazyman]

I think you can avoid shimmering in maxwell, if all tied to same seed number. Am I thinking right direction?

[rampally]

It would not flicker, but it would shimmer

can  you avoid that shimmering too!!!

[crazyman]

It would not flicker, but it would shimmer

can  you avoid that shimmering too!!!

wut?

[juang3d]

It will shimmer?

What do you mean? it will be brighter over time or something like that?

Cheers.

[Ondra]

No, because it is unbiased. The pixel values will oscillate between the true values. It will demonstrate as a light uniform high-frequency noise

[juang3d]

So with enough time, it will be clean, right?

Do you think that there could be a solution to avoid that noise? (In the future)

Cheers.