PencilCode/jquery-turtle — pull request #22 by davidbau (2014-01-21 22:54:26+00:00)
Title: This change adds a turtle method movexy for relative cartesian motion.

The reason to add the method is to simplify an introductory lesson on subclassing.

In http://activity.pencilcode.net.dev/edit/worksheet/classes.html, we ask students to try subclassing Turtle by adding velocity and spin properties, and a drift() method. Without @movexy, the drift method must do a bunch of verbose vector arithmetic to apply the velocity, which is not the point of the lesson. With @movexy, it is nice and concise.