A small sample of some utilities modified and released from a commercial project for use by others. C++ tested using TDM-2 mingw32 4.4.1 in Code::Blocks 10.05.
See also the shaders subfolder for some example shaders released from this project.
Usage notes 1: The unit vector_methods.hpp is dependant on the Box2D physics engine, in particular requesting b2Math.h. A simple vector class with similar method such as Set(x,y) and LengthSquared() could be supplanted in its place.
Usage note 2: These samples have been made pre C++11x with the flat to support preluminary C++0x features enabled.