Box2D is a physics engine written in C++ by Erin Catto. Box2D Lite is a simpler version which Erin posted to his blog once upon a time. This is a port of Box2D Lite to R6RS Scheme.
$ cd ~/scheme # Where '~/scheme' is the path to your Scheme libraries
$ git clone git://github.com/dharmatech/surfage.git
$ git clone git://github.com/dharmatech/dharmalab.git
$ git clone git://github.com/dharmatech/agave.git
$ ikarus --r6rs-script ~/scheme/box2d-lite/demos/small-pyramid.sps
$ scheme --program ~/scheme/box2d-lite/demos/small-pyramid.sps
$ larceny --r6rs --program ~/scheme/box2d-lite/demos/small-pyramid.sps
OpenGL library for Chez Scheme: chez-gl.
On my system, I keep R6RS libraries in ~/scheme. I keep chez-gl in ~/src.
So my CHEZSCHEMELIBDIRS is set like this in my ~/.bashrc:
export CHEZSCHEMELIBDIRS=~/scheme:~/src/chez-gl
$ ikarus --compile-dependencies ~/scheme/box2d-lite/demos/small-pyramid.sps
