[Jprogramming] draw rounded line/shape

[Sherlock, Ric]

While trying to create a gl2 version of the GUI for the Set Game
<http://www.jsoftware.com/jwiki/Scripts/Set_Game>, I wanted to draw a
"squiggle" shape (sort of backwards 's') that is usually used for one of
the card symbols <http://www.setgame.com/set/>. However I am uncertain
of how to go about this using the gl2 commands currently available in J.
How do you draw a wavy/rounded line or shape?

I'd also be interested in ideas on how to fill shapes with patterns
(rather than just shading them as I do now).