Search found 273 matches

by ingenious
Tue Jul 11, 2017 4:30 pm
Forum: General Development
Topic: MIS with IBL
Replies: 14
Views: 1979

Re: MIS with IBL

The problem is that the probability you use for choosing a light source is itself a random variable. If you write out the estimator you're building with your sampling techniques, its expected value won't be what you want. To get an unbiased estimator, you'll need to divide not by that random probabi...
by ingenious
Mon Apr 17, 2017 4:58 pm
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 26
Views: 5490

Re: Implementation for Blue-noise Dithered Sampling

The idea ideas not adding a deterministic (blue-noise) number to a random number. In fact, the idea is to get rid of the randomness altogether - you use the deterministic number to post your pattern, instead of using a random number. Regarding the (0, 0.99) vs (0, 0.01) issue, the answer is that it ...
by ingenious
Thu Feb 02, 2017 3:59 pm
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 26
Views: 5490

Re: Implementation for Blue-noise Dithered Sampling

To be honest, i don't even know if it can bring any real benefit for anything that is not directly visible from the camera. After all one exploits the human visual system here, so the higher dimensions/bounces should be better tackled via a properly distributed sample set (e.g. most likely some mod...
by ingenious
Tue Jan 31, 2017 6:33 pm
Forum: Tools, Demos & Sources
Topic: Implementation for Blue-noise Dithered Sampling
Replies: 26
Views: 5490

Re: Implementation for Blue-noise Dithered Sampling

toxie wrote:Would be interesting to hear your experiences when rendering with it, when optimizing for this 10D case. Cause IMHO the scheme should fall apart when using a large number of dimensions.


Indeed, in my experience it's hard (impossible?) to achieve high-quality blue noise in high dimensions :(
by ingenious
Fri Nov 11, 2016 11:03 pm
Forum: Links & Papers
Topic: Robust Light Transport Simulation via Metropolised Bidirectional Estimators
Replies: 5
Views: 6259

Re: Robust Light Transport Simulation via Metropolised Bidirectional Estimators

I think this is the answer. Given an endpoint on the eye subpath one can employ proper importance sampling on the light source for NEE (for example for spherical lights or environment map it is possible cull the part of the light source where the eye subpath can't see). It also reduces the correlat...
by ingenious
Wed Jun 15, 2016 12:08 pm
Forum: Visuals
Topic: GPU VCM
Replies: 30
Views: 14906

Re: GPU VCM

Thanks, very interesting!
by ingenious
Wed Jun 15, 2016 10:46 am
Forum: Visuals
Topic: GPU VCM
Replies: 30
Views: 14906

Re: GPU VCM

If I use a radius close to the projected pixel size the number of photons arriving per pixel is going to be low, right? That would probably lead to fireflies for quite a bit longer than the first 16-32 samples, which is the time frame I'm trying to optimize for. Indeed, this will inevitably increas...
by ingenious
Tue Jun 14, 2016 11:00 pm
Forum: Visuals
Topic: GPU VCM
Replies: 30
Views: 14906

Re: GPU VCM

Nice videos! I'd recommend using a smaller radius for vertex merging, something close to the projected pixel size, which would remove the nasty photon splotches. With VCM you can most often get away with using a small radius (unlike in PPM), because in the areas where merging is important the photon...
by ingenious
Thu May 05, 2016 11:41 pm
Forum: General Development
Topic: Regarding directional dipole
Replies: 4
Views: 1983

Re: Regarding directional dipole

If I remember correctly, the dirpole model includes single scattering, so in theory its result should be closer to the path traced reference. Can you actually please post that reference here for completeness?
by ingenious
Thu Mar 17, 2016 11:24 am
Forum: General Development
Topic: Energy conservation vs. energy normalization
Replies: 4
Views: 2587

Re: Energy conservation vs. energy normalization

shocker_0x15 , he does not have a problem with BRDF values going above one, and he actually computes a proper normalization factor by integrating the unnormalized BRDF. Indeed, in practice you will lose energy because when the reflected ray is not at normal direction, parts of the BRDF go below the...

Go to advanced search