A small library of composable multi-touch controllers for Codea that implement
various game control mechanisms.

A controller translates touch events into higher level callbacks to control
game objects.

The library includes an analogue joystick and slider with central dead-zone, 
a catapult style interaction for launching projectiles, and tap interpreters
that can be used as fire or jump buttons.

Controllers can be composed. A single statement can define a complex control 
scheme, such as used in a dual-stick shooter, or a shared-screen multiplayer
game, or a shared-screen multiplayer dual-stick shooter!

Example Codea programs that use the library can be seen at: 
* http://www.youtube.com/watch?v=aKetPVT7FO0
* http://youtu.be/B3ARwy1M5Jo?t=48s

Unfortunately, because Apple restrict what apps on iOS can do, you can no 
longer download the code directly into Codea.  You'll have to copy and paste
from the GitHub code browser.