Inline Scripting from a User's Point of View
============================================

The <script> Tag
----------------
  The <script> tag can be used for adding inline scripts into .display files.
  The script can either be entered directly between the <script> and </script>
  tags or saved as an external file to which is referenced by the "uri"
  attribute. It is possible to have more than one <script> tag, but all inline
  scripts in a .display share the same environment.

Action Handlers
---------------
  The second place where you can use scripts are the "on-xyz" action handler
  attributes in tags. Since action handlers share the same inline scripting
  environment you can call inline functions or access other elements from
  there.

The "self" Reference
--------------------
  Action handler scripts have access to the "self" reference, which represents
  the object where the action occurred.

Event Structure
---------------
  The "self" reference in an action handler contains an "event" with several
  properties depending on the type of event. A motion event e.g. has properties
  for the x and y coordinates of the mouse pointer:

    x = self.event.x
    y = self.event.y
    print "Current mouse pointer coordinate: (%d, %d)" % (x, y)
