Search found 6 matches

by T.C. Chang
Sun Mar 24, 2019 6:34 am
Forum: General Development
Topic: Shading normal issues w. adjoint bsdf
Replies: 7
Views: 868

Re: Shading normal issues w. adjoint bsdf

Haha, I was the one that filed the issue. In my implementation I keep the correction term since I do not like the idea of turning a consistent method into an inconsistent one. If I recall correctly, Jakob said that (in Mitsuba renderer) a better importance sampling technique is needed for the term. ...
by T.C. Chang
Wed Jul 18, 2018 10:59 am
Forum: General Development
Topic: Anyone read Laurent Belcour's paper on layered material?
Replies: 2
Views: 2169

Re: Anyone read Laurent Belcour's paper on layered material?

After thinking for a while, I think you are right. Partially filling the FGD table with FGD_inf is actually a good point, and I think the author meant that way. I am planning on implement this technique too. We can discuss about the details if there is any problem during implementation.
by T.C. Chang
Tue Jul 17, 2018 9:04 am
Forum: General Development
Topic: Anyone read Laurent Belcour's paper on layered material?
Replies: 2
Views: 2169

Anyone read Laurent Belcour's paper on layered material?

Laurent Belcour's recent paper on layered material looks amazing, here is the link https://belcour.github.io/blog/research/2018/05/05/brdf-realtime-layered.html . But I have got many questions regarding some formulae listed in the paper, especially equation 32 & 33. I think they are both missing the...
by T.C. Chang
Wed Jan 11, 2017 3:57 pm
Forum: General Development
Topic: PBRT-v3 (the book) wrong microfacet BTDF?
Replies: 3
Views: 5409

Re: PBRT-v3 (the book) wrong microfacet BTDF?

Thanks for your suggestion! But I'm not sure if it is okay to multi-post on several places since I already have posted a GitHub issue on PBRT-v3's repository. Actually I'm more confused than before after digging into this problem further. It looks like non of PBRT-v3, LuxRender, Mitsuba, Tungsten ar...
by T.C. Chang
Tue Jan 10, 2017 11:19 am
Forum: General Development
Topic: PBRT-v3 (the book) wrong microfacet BTDF?
Replies: 3
Views: 5409

PBRT-v3 (the book) wrong microfacet BTDF?

Recently I'm implementing path tracing with next event estimation and encounters a nasty bug: refracted radiance is higher than my path traced reference. Then I discovered that the paper by Walter et al. (Microfacet Models for Refraction through Rough Surfaces) writes the microfacet BTDF formula wit...
by T.C. Chang
Thu Jan 05, 2017 5:58 pm
Forum: Visuals
Topic: Glitch Pictures anyone?
Replies: 81
Views: 110621

Re: Glitch Pictures anyone?

After a bad refactor of my simple path tracer :shock:
bad refactor cornell box.png
bad refactor cornell box.png (427.77 KiB) Viewed 7573 times