PhotonGI cache

[lacilaci]

Yes it's all great and even some bias is great. I'm personally pretty confident with the feature by now, but for new users it might be important in the future to automatize what can be automatized. Or some quickstart-guide to point people to when they ask would be also good.

Another small annoyance that comes to mind is "usage threshold scale" the name doesn't seem correct to me. Wouldn't it be more acurate as "usage distance scale" or "distance threshold scale"? Or is even scale a proper name? isn't this a multiplier?

[Sharlybg]

Fair Fight without OIDN in the mix. PGI vs Path :


Path 1mn GTX 1080ti

PGI 1mn GTX 1080ti

PGI Debug

[Sharlybg]

And PGI with Normal Angle of 90°:

Light is Back

PGI 1mn 1080ti + 90° normal angle

Wonder why is that and why normal angle default is so low if it can improve thing at 90°. is there any Lost

[lacilaci]

@Sharlybg try also using 10-15cm lookup and usage threshold of 1 and 90 degree normal angle. Should be much faster even.

[Dade]

It looks too dark to me without 90deg normals, I will investigate more the topic.

[Sharlybg]

@Sharlybg try also using 10-15cm lookup and usage threshold of 1 and 90 degree normal angle. Should be much faster even.

Done here is the result : Note i just increase a little bit the exposure in color management

Set.png (31.91 KiB) Viewed 4590 times

[lacilaci]

I think for max size a 1000 or 2000 should give same result but faster precomputation

[lacilaci]

I think all materials should build cache for diffuse rays.

Also cache size and photon count should be calculated to fill some criteria, maybe coverage in screen space or something, instead of guessing how much photons to cast and how big cache should be

lookup size should be 15 cm hardcoded
usage threshold should be 1 hardcoded
glossiness of 0.1 should be hardcoded
normal angle should be 90 or some other fix for dark rendering should be presented as default/hardcoded value

Basically what I'm suggesting is, fill screen with cache entries of 15cm radius and use 1 for usage threshold scale by default. For glossy rays use 0.1 threshold and for diffuse use 0.0

The thing that needs to be discovered here is of course, how to automatically determine when you have enough photons.

[Fox]

Why to hardcode lookup size at 15cm?
I use 0.5 cm for small scale scene, the total scene has the size of 20cm.

[Dade]

Also cache size and photon count should be calculated to fill some criteria, maybe coverage in screen space or something, instead of guessing how much photons to cast and how big cache should be

Screen coverage would be a good criteria, the problem is in having a constant radius: one pixel covers 15cm at 1m of distance and 150m at 1km (random numbers, just to give you an idea of where the problem is).