I’ve put together a “Sketch” Template for Processing, that includes a skeleton for mouse and keyboard interaction. It also includes code for recording your sketch in PDF, Quicktime Movie, and PNG. It’s a little rough. I do have to advise that the more complicated you make your sketch, the higher likely hood that you can have conflicting code. So if you start of with this template, parts of it might conflict with other libraries and code. But for fairly basic sketches this should be a good starting point.