Search found 97 matches
- Fri Jan 19, 2018 4:16 pm
- Forum: Visuals, Tools, Demos & Sources
- Topic: SIMDy
- Replies: 7
- Views: 16221
Re: SIMDy
While this looks interesting for Python developers, I still prefer developing my renderers with C++. And for C++ SIMD development, I found Vc ( https://github.com/VcDevel/Vc ) to be a very good library (it is one of the two libraries being proposed for future C++ standardization, the other one being...
- Wed May 04, 2016 9:50 pm
- Forum: General Development
- Topic: How to measure "real" material for rendering
- Replies: 11
- Views: 14823
Re: How to measure "real" material for rendering
Also, I find a lot of today customers expect spatially varying BRDFs. Especially those customers dealing with textiles materials. SVBRDF produce huge data files though.
- Fri Apr 29, 2016 9:37 pm
- Forum: General Development
- Topic: How to measure "real" material for rendering
- Replies: 11
- Views: 14823
Re: How to measure "real" material for rendering
It depends on the accuracy of the measure you want. Start by looking at "Gonioreflectometers". It's only a good start. It can get much more sophisticated than that.
- Thu Jan 07, 2016 9:21 pm
- Forum: Data Sets
- Topic: Bezier surface models
- Replies: 4
- Views: 14950
Re: Bezier surface models
If you are interested in nurbs patch models, then you might be interested in looking at Animation:Master. A 3D animation software that models using nurbs patches. You will find the A:M users community here: https://www.hash.com/forums/ . There is a fair number of patch models available. Plus you can...
- Wed Jul 08, 2015 11:35 pm
- Forum: General Development
- Topic: pbrt-v3 source code now available
- Replies: 23
- Views: 25279
Re: pbrt-v3 source code now available
On page 214, I don't understand the sentence "When working with these error intervals, it’s important to remember that because (1 ± em) terms represent intervals, canceling them incorrect:" Seems fine to me. Although the numerator and denominator contain the same 'term', they don't cancel because t...
- Wed Jul 08, 2015 12:25 am
- Forum: General Development
- Topic: pbrt-v3 source code now available
- Replies: 23
- Views: 25279
Re: pbrt-v3 source code now available
On page 214, I don't understand the sentence "When working with these error intervals, it’s important to remember that because (1 ± em) terms represent intervals, canceling them incorrect :" On page 219 "then it’s impossible to tell whether it is exactly zero or whether a small positive negative val...
- Tue Jul 07, 2015 5:37 pm
- Forum: General Development
- Topic: pbrt-v3 source code now available
- Replies: 23
- Views: 25279
Re: pbrt-v3 source code now available
I'm reading the chapter on floating point precision. I was surprised to read that one can use an "enum" for casting between two different representations. I did not try that but I used to use a "union" for that. Edit: I see that the "union" is later mentioned. So I say that the two use of "enum" are...
- Mon Apr 06, 2015 7:54 pm
- Forum: General Development
- Topic: cosine lobe sampling PDF
- Replies: 11
- Views: 15610
Re: cosine lobe sampling PDF
Intuitively When you look at the density of a uniform hemispherical distribution, it looks like a hemisphere. Thus its surface is 2pi. If you look at the density of a cosine distribution, you will observe that it is, itself, a sphere of one unit diameter or 0,5 radius above the surface. Thus its sur...
- Tue Mar 10, 2015 1:37 am
- Forum: General Development
- Topic: Some images from my renderer
- Replies: 8
- Views: 7414
Re: Some images from my renderer
My renderer has a layered shading system not too dissimilar from Vray's layered shader or Renderman 19/RIS's LM system. So the chair uses a layered BSDF with a base diffuse BSDF with the color, and then a clearcoat layer on top and then a couple of layers with fingerprints and scratches and stuff, ...
- Tue Mar 10, 2015 1:29 am
- Forum: General Development
- Topic: Defining roughness
- Replies: 6
- Views: 5759
Re: Defining roughness
Walter et al paper "Microfacet Models for Refraction through Rough Surfaces" gives equivalency functions for Beckmann roughness, vs Phong exponent but no equivalency for GGX, strangely. Blinn in "Models of Light Reflection for Computer Synthesized Pictures" gives equivalency functions for Phong expo...