PhotonGI cache

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epilectrolytics
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Re: PhotonGI cache

Post by epilectrolytics »

Dade wrote: Fri Jan 18, 2019 4:09 pm You mean PATHCPU, right ? PATHOCL is unchanged for the moment.
PathCPU of course, sorry.
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Re: PhotonGI cache

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epilectrolytics wrote: Fri Jan 18, 2019 4:18 pm
Dade wrote: Fri Jan 18, 2019 4:09 pm You mean PATHCPU, right ? PATHOCL is unchanged for the moment.
PathCPU of course, sorry.
BTW, the slowdown is usually the effect of having a very large cache search radius and having many thousands of photon falling inside the search radius. Try to change the radius and you will see how the samples/sec number goes up and down.

I may have to switch from a BVH look up accelerator structure to a Kd-tree in order to solve this problem but it is something I will look into when things are a bit more settled down.
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Re: PhotonGI cache

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Haha, it works, this is a rendering with 15 samples/pixel of LuxCore Benchmark and cache:

cache.jpg

And this without cache:

no-cache.jpg

Notice the huge difference of noise in indirect lighting (like under the table, etc.). And with only about 6 seconds of pre-processing:

preprocess.jpg

I have to work on the samples/sec performance but PhotonGI is going to reduce the rendering times by a lot.
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Re: PhotonGI cache

Post by Sharlybg »

:shock: GOING to be more than we expected .coding Sensei Mode ON :twisted:
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lacilaci
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Re: PhotonGI cache

Post by lacilaci »

Dade wrote: Fri Jan 18, 2019 4:51 pm I have to work on the samples/sec performance but PhotonGI is going to reduce the rendering times by a lot.
I think the latest estimate I did way back using corona was about 8x speedup using PT+UHDC vs PT+PT.
Funny thing is that although caching is mostly recommended for interiors it still helps a lot even with exterior renderings and basicaly everything that includes shadow areas...
So unless its a super simple scenario, everything should benefit from using caching, that's why it's on by default for vray and corona aswell.
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Re: PhotonGI cache

Post by Dade »

Dade wrote: Fri Jan 18, 2019 4:51 pm I have to work on the samples/sec performance but PhotonGI is going to reduce the rendering times by a lot.
I have moved some BSDF evaluation step from the rendering phase to the pre-processing phase and now the rendering is about 4-5 faster (!) at the cost of a slight increase in pre-processing time:

fast.jpg

If you check the previous post, the samples/sec were 0.17M samples/sec and are now 0.68M samples/sec (so it is 4 times faster) at the cost of an increase of pre-processing time from 6secs to 20secs.

The rendering with cache enabled is also now faster than without cache (0.68M samples/sec Vs 0.50M samples/sec). It is faster in term of samples/sec and it has a lot less noise. The result with 150 samples per pixel is quite good in term of noise. This thing is gone to be quite fast when you throw the GPUs in the mix :D
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Re: PhotonGI cache

Post by B.Y.O.B. »

Would it be possible to get a preview of the cache while it is building?
To spot stuff like the artifacts on the doorframe quickly.
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Re: PhotonGI cache

Post by Dade »

B.Y.O.B. wrote: Sat Jan 19, 2019 1:41 pm Would it be possible to get a preview of the cache while it is building?
To spot stuff like the artifacts on the doorframe quickly.
Yup, this: viewtopic.php?f=5&t=840&start=30#p8884
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Re: PhotonGI cache

Post by lacilaci »

I wonder why that doorframe even has those artifacts when other detailed geometry seems to look clean.
Fantastic progress btw.
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Re: PhotonGI cache

Post by epilectrolytics »

Dade wrote: Fri Jan 18, 2019 4:51 pm Haha, it works, this is a rendering with 15 samples/pixel of LuxCore Benchmark and cache:
:shock: Amazing!

I thought there is a poor rate of photons registered from sunlight but fortunately it seems I was wrong :D
And yet still without metropolis photon gathering, right?

Would this work with an HDRI as well?

Great progress, keep it up!
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