StarLogo Project:
Turtle Graphics
WHAT IS IT?
There is a long tradition of using the Logo turtle to create
"turtle graphics" drawings. By enabling multiple turtles
move (and draw) in parallel, StarLogo greatly expands the
possibilities for turtles graphics. This project presents a
collection of StarLogo turtle-graphics programs.
HOW TO USE IT
For each program, first click the setup button, then click
the corresponding go button.
THINGS TO NOTICE
In the first two programs, the turtles draw patterns with
their pens (in classic Logo style). In the other programs,
the turtles themselves form the patterns.
In all of these programs, the turtles simply draw circles.
Nothing more. Interesting patterns are created by
starting the turtles with interesting initial conditions,
and by having some turtles "hatch" other turtles. But when
the turtles move, they simply draw circles, nothing more.
EXPLORATIONS
Modify the underlying programs. Observe how small changes in
the programs can lead to major changes in the resulting
patterns.
STARLOGO FEATURES
Several of the turtle-graphics programs use the following
trick: make several turtles rotate in place (in the middle
of the screen) and "hatch" a stream of new turtles as they
rotate. The newly hatched turtles typically draw a circle
and then die. This simple technique creates some spectacular
effects.
