Search found 75 matches
- Sat Jul 13, 2019 3:02 pm
- Forum: General Development
- Topic: Light-tracer weights
- Replies: 9
- Views: 3476
Re: Light-tracer weights
If I understand you correctly, by omitting this PDF in the pathtracer I need an additional weigh in the lightracer, right? Correct. Quoting PBRT again, are you talking about the following PDF? Yes. We need to pay attention when talking about light-tracing (and Bidirectional Path Tracing), so I need...
- Thu Jul 11, 2019 1:41 pm
- Forum: General Development
- Topic: Light-tracer weights
- Replies: 9
- Views: 3476
Re: Light-tracer weights
I don’t mean the naive pathtracer implementation by “division by PDF to generate the first intersection point”. Do your path tracing implementation (both with and without NEE) take the “PDF to generate the first intersection point” into account? That PDF is a PDF to generate a primary ray from a cam...
- Thu Jul 11, 2019 8:51 am
- Forum: General Development
- Topic: Light-tracer weights
- Replies: 9
- Views: 3476
Re: Light-tracer weights
I think it depends on the ground truth implementation.Why do you think it shouldn't be there?
What is your expected brightness? Is it the result of path tracing?
If so, does it contain the division by PDF to generate the first intersection point (the second vertex if the first is on lens)?
- Wed Jul 10, 2019 5:44 pm
- Forum: General Development
- Topic: Light-tracer weights
- Replies: 9
- Views: 3476
Re: Light-tracer weights
However sometimes I see an implementation of path tracing which omits the division by the PDF of the first intersection (i.e. PDF for the next vertex to a point on lens). If you want to match the result to the implementation like this, you need to take additional factors to light-tracing into the ac...
- Wed Jul 10, 2019 5:23 pm
- Forum: General Development
- Topic: Light-tracer weights
- Replies: 9
- Views: 3476
Re: Light-tracer weights
I strongly suspect it is related to sample weights, when I connect to the camera. For now I only consider a pin hole camera with a lens radius of zero. Does “connect to the camera” mean that you are trying to do NEE with light tracing? If so, I have feeling that your weight calculation contains man...
- Sat Feb 23, 2019 9:58 am
- Forum: General Development
- Topic: Shading normal issues w. adjoint bsdf
- Replies: 7
- Views: 3811
Re: Shading normal issues w. adjoint bsdf
It might be help for you to visualizing the relation between geometric normal and shading normal like this: clamp( RGB( 0.5 + 10 * (dot(shadingNormal, geometricNormal) - 1), 0.5 + 100 * (length(geometricNormal) - 1), 0.5 + 100 * (length(shadingNormal) - 1) ) , 0, 1) This shows completely a gray imag...
- Fri Feb 22, 2019 3:14 am
- Forum: General Development
- Topic: Shading normal issues w. adjoint bsdf
- Replies: 7
- Views: 3811
Re: Shading normal issues w. adjoint bsdf
I don’t have a clear answer for your question, but I think there is a limitation with shading normal because it doesn’t have physical basis (as Veach noted). One apparent way to mitigate arbitrarily large values is using well polygonized model which has shading normal similar to geometric normal... ...
- Thu Sep 20, 2018 1:41 pm
- Forum: Links & Papers
- Topic: CUDA 10 available
- Replies: 6
- Views: 12442
Re: CUDA 10 available
We can already find a description about new features in the next OptiX from Google search (e.g. GeometryTriangles).
According to that, the next version of OptiX becomes 5.2
According to that, the next version of OptiX becomes 5.2

- Mon Mar 05, 2018 5:23 pm
- Forum: General Development
- Topic: Geometry factor for parallel light?
- Replies: 2
- Views: 5218
Re: Geometry factor for parallel light?
I'm not sure if I understand your question, but I think 1 / r^2 term should always be considered and is implicitly considered if you trace a path from the light source even if it is parallel light. Light path construction is performed as follows: sample a point y0 on the light with pdf p_A(y0) and g...
- Fri Dec 08, 2017 6:34 pm
- Forum: General Development
- Topic: Why is volumetric emission proportional to absorption coefficient?
- Replies: 7
- Views: 15237
Re: Why is volumetric emission proportional to absorption coefficient?
My current thinking process when reading the paper you lastly mentioned is like following: 0. However, the mental model behind radiance transfer is not one that considers the interaction of individual particles. - Yes, I know. 1. eq. (1) says that contribution from source radiance Lm(x', w) is propo...