Search found 164 matches

by jbikker
Thu Feb 09, 2017 11:32 am
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 25
Views: 2568

Re: Implementation for Blue-noise Dithered Sampling

This is unidirectional path tracing with uniform random variables everywhere, 8 bounces, RR, MIS, NEE, Lambert BRDF.
Left side replaces uniform random variables with the tile. For subsequent pixels I shift the tile randomly over x and y, instead of adding an offset to each value.
by jbikker
Wed Feb 08, 2017 12:41 pm
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 25
Views: 2568

Re: Implementation for Blue-noise Dithered Sampling

OK, did some quick tests: - Applying the method to direct light sampling yields the results presented in the paper. - Applying the method to the first diffuse bounce yields no perceivable improvement in quality. In general, the number of dimensions is a problem: I tried 6 dimensions (sampling direct...
by jbikker
Tue Jan 31, 2017 8:07 pm
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 25
Views: 2568

Re: Implementation for Blue-noise Dithered Sampling

It's currently improving my 128^2 tile... Spent 78 hours so far. :) Added progress counter and resume functionality. I'll report when I have something running, but it's going to be after the weekend; tracer is broken atm due to some BSDF experiments.
by jbikker
Thu Jan 26, 2017 8:57 am
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 25
Views: 2568

Re: Implementation for Blue-noise Dithered Sampling

I set the tile size to 64, iterations to 65536 * 2 and depth to 10 (for: lens, pixel, light sample 1, diffuse bounce, light sample 2); in that case the code takes about 1.5 *hours* to execute on a 12-core Xeon system (admittedly, old Xeons)... How long did your 128x128 tiles take? :)
by jbikker
Tue Jan 24, 2017 2:46 pm
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 25
Views: 2568

Re: Implementation for Blue-noise Dithered Sampling

That is very interesting, thanks for the links!
by jbikker
Tue Sep 27, 2016 10:52 am
Forum: General Development
Topic: AVX512 MBVH4 Traversal
Replies: 8
Views: 3706

Re: AVX512 MBVH4 Traversal

Could you also test divergent rays? Architectures that rely on caches (i.e. CPUs) seem to suffer greatly from divergent mem access, while architectures that hide latencies using many threads typically fare much better. I would be suprised to see that the latest CPU-like device outperforms the latest...
by jbikker
Mon Jul 25, 2016 8:03 am
Forum: Visuals
Topic: GPU VCM
Replies: 30
Views: 12644

Re: GPU VCM

I present a frame after doing a full 8-bounce sample for every pixel (although most paths will be shorter due to Russian Roulette; the cap of max length 8 is for individual light paths, individual eye paths and combined paths, as in SmallVCM). Doing this in a reasonable amount of time is currently n...
by jbikker
Thu Jul 14, 2016 7:42 am
Forum: Visuals
Topic: GPU VCM
Replies: 30
Views: 12644

Re: GPU VCM

I didn't implement them for a performance boost, but to be able to keep counters on the GPU. If you produce N shadow rays in one kernel (shading), you either spawn N threads for the next kernel (tracing shadows), or you run SMCount*128*4 threads persistent shadow tracing code. Spawning N threads req...
by jbikker
Thu Jul 07, 2016 9:16 pm
Forum: Visuals
Topic: GPU VCM
Replies: 30
Views: 12644

Re: GPU VCM

Yes I was a bit surprised to get it this fast. I mean, there's an impact for all the I/O, but pretty low; for any decent amount of triangles the gains of the improved occupancy are going to outweigh the costs. I noticed before that the wavefront paper is not optimistic enough about this; even a very...
by jbikker
Thu Jul 07, 2016 5:53 pm
Forum: Visuals
Topic: GPU VCM
Replies: 30
Views: 12644

Re: GPU VCM

Sorry, no, this will be closed source.

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