Search found 20 matches
- Sun Jul 09, 2017 8:48 pm
- Forum: General Development
- Topic: MIS with IBL
- Replies: 14
- Views: 11305
Re: MIS with IBL
One thing that I realized is that when the random selected light happens to be behind the point that is being evaluated the potential contribution is 0, and therefore the sky will be selected with a probability of 1. However, another light may in fact be visible, so when I stumble upon it the MIS p...
- Mon Sep 28, 2015 11:13 pm
- Forum: General Development
- Topic: Sobol' sequences
- Replies: 11
- Views: 11515
Re: Sobol' sequences
Yeah I think CMJ performs pretty well from what I've seen, but still suffers from the limitation that you've got to know your sample count up front.
- Mon Sep 28, 2015 11:08 pm
- Forum: General Development
- Topic: Sobol' sequences
- Replies: 11
- Views: 11515
Re: Sobol' sequences
I just tried halton this afternoon and found it to be slightly worse than sobol in a naive implementation. I also looked at your code and tried reordering the low dimensions as you do but found that gave me more noise than the default ordering. I think I need to spend some more time tweaking the imp...
- Mon Sep 28, 2015 3:19 pm
- Forum: General Development
- Topic: Sobol' sequences
- Replies: 11
- Views: 11515
Re: Sobol' sequences
Actually looking back at my code, both examples were with 1024 samples. At 4096 samples the 14,15 space is completely covered, although I think the 24,25 space needs 8192 samples to be covered. How does the Faure-permuted Halton perform at lower sample counts?
- Mon Sep 28, 2015 1:30 pm
- Forum: General Development
- Topic: Sobol' sequences
- Replies: 11
- Views: 11515
Re: Sobol' sequences
That does look a lot better, I'll give it a go, thanks! Does it have any bad 2d projections in other dimensions?
- Wed Sep 23, 2015 3:43 pm
- Forum: General Development
- Topic: Sobol' sequences
- Replies: 11
- Views: 11515
Re: Sobol' sequences
Thanks toxie. After thinking about it some more I'd sort of realised that was the case. I guess in the limit then the sequence explores the whole sample space in a nicely-distributed fashion, which isn't necessarily what I'm after.
What's considered "state of the art" these days?
What's considered "state of the art" these days?
- Mon Jul 27, 2015 5:56 pm
- Forum: General Development
- Topic: pbrt-v3 source code now available
- Replies: 23
- Views: 23305
Re: pbrt-v3 source code now available
In the BeckmannSample11 function in microfacet.cpp you have special logic to check for whether we're at normal incidence and sample the slope directly, but then the rest of the function continues as normal and *slope_x and *slope_y will be overwritten. Shouldn't the function return after line 48? ht...
- Sun Jul 05, 2015 3:15 am
- Forum: General Development
- Topic: Looking for textures for material preview scene
- Replies: 2
- Views: 5054
Re: Looking for textures for material preview scene
I have a Maya shaderball scene you can use as a starting point here (scroll down to the bottom of the page):
http://anderslanglands.com/alshaders/
It's set up for Arnold but should be easy to adapt for your purposes
http://anderslanglands.com/alshaders/
It's set up for Arnold but should be easy to adapt for your purposes
- Wed Jun 10, 2015 2:18 am
- Forum: General Development
- Topic: Sobol' sequences
- Replies: 11
- Views: 11515
Sobol' sequences
I'm trying out Leonhard Gruenschloss's Sobol'-seqeunce generator from here: http://gruenschloss.org/ The first two dimensions look as expected (0,1): http://i.imgur.com/4iDfBKG.jpg but higher dimensions show the poor projections that I thought the "better 2d projections" paper was supposed...
- Tue Sep 02, 2014 3:38 pm
- Forum: Links & Papers
- Topic: GACV : robust numerical integration method
- Replies: 2
- Views: 6451
Re: GACV : robust numerical integration method
This sounds interesting! Can you share the preprint any other way? I can't create an account on that site to be able to view it.