POLYSTART
Starts the definition of a new polygon. Each subsequent move while the turtle's pen is down adds the destination coordinate as a vertex to the polygon. The polygon's definition is completed by running the POLYEND command.
Make sure you understand the Polygon Restrictions.
After all of the polygons are defined, you can view them as shaded polygons by running the POLYVIEW command.
POLYSTART is designed to run in PERSPECTIVE mode and does not run in 2D modes.
TO SQUARE
POLYSTART
REPEAT 4 [FORWARD 100 RIGHT 90]
POLYEND
END
PERSPECTIVE
REPEAT 72 [SQUARE RIGHTROLL 5]
POLYVIEW