This is very interesting, and a good collection of algorithms. But before digging I didn't know what Church [0] was, and took me a while to figure out that this is what the algorithms are written in. You may want to put a note on the page somewhere for those new to the language.

[0] http://projects.csail.mit.edu/church/wiki/Church

For context: https://probmods.org "In this book, we explore the probabilistic approach to cognitive science, which models learning and reasoning as inference in complex probabilistic models. In particular, we examine how a broad range of empirical phenomena in cognitive science (including intuitive physics, concept learning, causal reasoning, social cognition, and language understanding) can be modeled using a functional probabilistic programming language called Church."

The Github repository because the link on the page returns 404: https://github.com/forestdb/forestdb.org

This is not about procedural 3D models but something unspecified I have no clue about.

It is about generative models - models that let us draw samples from complicated distributions.