The vecmath library

This library now replaces the arcball library, so where previously you may have used load_library :arcball, you now need to load_library :vecmath. However the main purpose of this library is provide a more rubified version of the processing PVector library, that apart from not having a very ruby like interface, appears to be trying to do too much. PVector is designed to be used for either 2D or 3D vector work, the vecmath library separates out these concerns to two classes Vec2D and Vec3D ( see also Vec2DR that extends Vec2D to support rotate(scalar)). Between them theses classes provide most of the PVector functionality. There is no need implement the PVector get() method, to return a copy of called the PVector (what's wrong with a copy constructor processing is java after all?), clone works perfectly well for both Vec2D and Vec3D in ruby-processing. However there is less need to clone Vec2D and Vec3D (than use the counter-intuitive PVector get()) owing to the fact that most operations (+, -, /, *) return a new instance. For the future it might be nice to extend the vecmath library to support rotational geometry, already included is Quaternion class but this is currently only designed to support arcball manipulations. Worked examples of the vecmath library are included in samples/processing_app/library/vecmath folder.