Yamanote Line (javascript)

This is the same thing as the Windows Console game translated into javascript. I would have enjoyed implementing simplistic 3D graphics using WebGL/Three.js, but it turns out the physics computation is so heavy that even just looping cubes passing by would not run smoothly, so I just took console screenshots as sprites. Captain obvious says: when boolean switches get out of control (like in the original c++) use enums instead. But javascript doesn't have enums as such so you need to take a minute to decide how to get that mutual exclusivity, and in addition you can use freeze() to block reassigments. Here I do not care about freeze because nobody will ever touch those states. Pre-fix "view-source:" to the URL if you want to see the code.