A Short introduction to using Logo. This is the first in a twelve part series.
Can you use LOGO to create this star pattern made from squares.
Only basic LOGO knowledge needed.
Using LOGO, can you construct elegant procedures that will draw
this family of 'floor coverings'?
First Forward Into Logo
In FF4 you investigated the instruction:
REPEAT 360 [FD 1 RT 1]
Hopefully you altered it as you saw fit and produced some exciting shapes. So it is timely to introduce you to the idea of a variable . As the word implies, a variable is something that varies, something that changes.
You may find the following a quicker way of drawing circles and circular patterns. It is called a procedure and has to be written in a particular way.
TO CIRCLE :CH
REPEAT 360 [ FD :CH RT 1]
Notice how the procedure is set out:
First a title / a command TO CIRCLE
then the variable :CH
followed by the instructions REPEAT 360 [ FD :CH RT 1]
then a formal closing of the procedure END
N.B. the variable, :CH could have been any letter or letters that you wish!
Building on this idea of a procedure we could have written:
TO CIRC :CH :ANG
REPEAT 360 [ FD :CH RT :ANG]
This is a procedure with two variables!
Can you anticipate what will change and what will happen now?
Can you see what is now possible?
Go on experiment! Try:
CIRC 3 3
CIRC 3 6
CIRC 3 30
What is happening?
What do you notice?
What conclusions can you come to?