Hey man, really glad you enjoyed it! I'll dunk the code in here so you can have a look - I had to dig it out of an old folder - just promise you won't judge as I wrote this YEARS ago while I was still learning, so it's a bit rubbish... still works though...
I added a version of the source code to download from the page (Delta_source), so you could have a look, but in doing so it looks like i've broken the embedded version of the game... whoops.