In the 4th edition of "Physically Based Rendering" here:pbrt book 4th ed Section 2.4in Section 2.4 "Transforming between Distributions", it is said "Suppose we are given a ...

Many render engines implement the microfacet model for rendering surfaces that are rough, metallic, and/or transparent, a concept first published in "A Reflectance Model for Computer Graphics&...

I'm not sure I have the right terminology, but in rendering it can be useful to draw cosine weighted samples from a hemisphere. In this case the integral (over the weights) is Pi.Now I don´t want to ...

I would like to implement a random placement for objects like trees stones etc. on a triangles surface.The important part is to have an equally probability to place an object on this surface. That ...

Why does the equation at the bottom of the following page hold?http://www.pbr-book.org/3ed-2018/Monte_Carlo_Integration/Transforming_between_Distributions.html$p(\theta,\phi)d\theta d\phi=p(\omega)...

I am working on a procedural placement system on the GPU, inspired by the work done by Guerrilla Games in Horizon Zero Dawn:https://www.guerrilla-games.com/read/gpu-based-procedural-placement-in-...

In a BRDF $f_r$, assume Cook-Torrance model, we have a microfacets distribution $D$. This distribution essentially models the rougheness of the material as far as I've understood. Given a direction $v$...

UpdateI am editing and posting this question in a different way; this time from the point of view of Nishita paper.Sunlight gets scattered at P and attenuated before reaching Pv. Therefore ...

I'm currently learning mathemetical concepts of distribution and the way to use them in a ray tracer with the book "Physically Based Rendering".Let's start by uniformly sampling an hemisphere:As ...

I am attempting to visualize the raw output from PBRT's half-vector sampling function, based on the trowbridge-reitz distribution. I'm isolating only the distribution and the associated functions ...

I am learning ray tracing and the mathematics behind it. I have a working monte-carlo raytracer I am experimenting on. I have gotten past pure diffuse BRDFS, area lights, acceleration structures, ...

I'm having trouble understanding the JFA. As far as I understood the algorithm, it walks log(n) times through every pixel (no matter if it is a seed or not) and looks at that pixel's neighbors in $(x+...

I am trying to implement my own path tracer but before arriving to the question I want to give you a short overview:In the implementation of the rendering equation I use some particular technique in ...

In Understanding the Masking-Shadowing Function in Microfacet-Based BRDFs, Section 2.2, Mr Eric Heitz defines the distribution of normals as:And then, he goes on with the following assertion:I fail ...

As explained in Holger Dammetz page Hammersley Points on the Hemisphere, the 2D coordinates (u,v) are usually mapped to the spherical coordinates (θ, φ).As a result, the coordinate "uniformly ...