I wrote an article on collision detection for Build New Games, and it’s live! Check it out here. If that link ever dies, you can read the archived article.

For this article, I wrote a demo engine, and the whole thing is on Github for easy perusing. Something I discovered is that if you create a project/repo on Github, and then only push the gh-pages branch, it is used as the default automatically, and you never have to worry about committing/syncing between master and gh-pages. NEAT.