PhotonGI cache

[Sharlybg]

I should have finally fixed the darker output of PhotonGI. This is an old test rendering

Thanks Dade for the hard work !

When can we test this update ?

[Racleborg]

I assume we are in a pretty good spot if people complain for rendering this in 10mins ... on a i7 2600

Mind blowing stuff

[epilectrolytics]

Like I wrote is "mostly" lost because I'm averaging the amount of light reflected by material over the entire hemisphere. This is the average of a constant value for matte, while for glossy is the average of different values. The "shiny" part of gloss is averaged over all the hemisphere (so energy is not lost, it just more "smooth").

If you want to study the problem, you can use indirect cache debug view. If it is not yet clear it is a complete rendering and it should match the output of a normal rendering (splotch-ness aside).

Look this is a rendering with a glossy with 0.0 diffuse and 0.95 specular, PGI rendering:

See how PGI makes the surface look like a diffuse material while the reference is truly glossy. This is the bias introduced in this case however just look at other surfaces, the difference in indirect light is very small (and it is what PGI cache is used for).

Indeed, if all the right wall is black, the bias is huge.

Very interesting!
So for the cache entries directional light is not omitted but averaged which should cause a distributional bias and not one of amount (of light).
I will do some testing later with the newest build, thanks for those examples!

[Sharlybg]

I will do some testing later with the newest build, thanks for those examples!

New build with applied fix when where ? Need some drugs please

[lacilaci]

I will do some testing later with the newest build, thanks for those examples!

New build with applied fix when where ? Need some drugs please

It's up... I'm testing it now...

[lacilaci]

So, yes.. brightness seems to work now as expected.

250mil photons 10cm lookup 8 depth:

pathtracing:

only 450K photons and 32depth at 30cm lookup radius:

There seem to be 2 ways of preserving light in photon gi... more depth or more photons. Path depth seem to be less taxing than huge amount of photons.
Also, even 250 000 000 photons at 10cm lookup radius seem to produce fireflies/lightleaks/bleeding.

But it's the only problem left now it looks like

[Sharlybg]

SOooooo Cooooool it work like in a dream ! Very Good Job Dade the result are even better (less noise).

PGI

PGI + Denoise

[Dade]

I added Russian Roulette to PhotonGI photon tracing, this will reduce the pre-processing time with high max. depth values.

[Sharlybg]

I added Russian Roulette to PhotonGI photon tracing, this will reduce the pre-processing time with high max. depth values.

Can i Download now ?

[lacilaci]

I added Russian Roulette to PhotonGI photon tracing, this will reduce the pre-processing time with high max. depth values.

Can i Download now ?

if you want a windows build, then probably in an hour to be safe. It's still testing.