To increase object-orientedness, could all

e.printStackTrace

be replaced with

printException(Throwable e)

in Papplet.java ? Then those of us wanting to extend the error handling capabilities
(i.e., if we have many registerDraws() that could throw exceptions), we could just
override this single method.

yeah, this is on the todo list but didn't have a bug number assigned to it.
we do this with the die() method that handles fatal exceptions, but i need
to make the implementation more consistent, and add a warn() method that
would handle cases like the one you describe.