CS 111 - 9/13/12

Sequence of Instructions

ORDER IS VERY IMPORTANT!!!

Variable values only change during an assignment.


Chapter 3: Turtle Drawings

  Step 1:  Create a world/picture

  Step 2:  Create a Turtle to live in the world/picture

  Step 3:  Move the turtle around; do something with it

  Step 4:  Show the world/picture

Previous variable declarations were done with primitive types

World and Turtle are Objects

When a variable declaration is done for an object,
    we just create space to store the object,
    we don't actually create the object.

Basic Turtle operations/methods

   t.forward ( );
   t.forward ( 50 );
   t.turnLeft ( );
   t.turnRight ( );
   t.turn ( 90 );
   t.penUp ( );
   t.penDown ( );
   t.setPenColor ( Color.BLUE );