This is a 2d visibility algorithm described in this article, ported by hand to JavaScript (ES2016) and refactored significantly to suit my taste better. I went for a more functional approach and renamed/reorganized some things, so it's not quite a 1-to-1 port.
I highly suggest reading the article. It's very well explained with some really awesome interactive examples and provides the code in multiple languages. The original code was written in Haxe, which can compile into JavaScript but I found the generated JS to be rather difficult to read and comes with an (unnecessary) doubly linked list implementation.
There's also a fork of this repo in TypeScript.
Clone the repo, npm install then run webpack-dev-server --content-base . and navigate to localhost:8080
The MIT License (MIT)
Copyright (c) 2016 Cyril Silverman
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