Introduction

cut and paste the code into TileLand.
tileland.png

Sequences of instructions

I start with three instructions ... this allows for snake patterns (like the game snake). All the instructions are one letter.
4  -- square
>  -- clockwise or right  (. works as well)
<  -- counter-clockwise or left (, works as well)
 
4444 -- makes a column of 4 squares
4<44>444 -- makes a big L
The key idea is that there is an active side where the next square will be placed. The right and left instruction changes which is the active side.

Colouring makes it easier to refer to certain squares and is not conceptually tricky.
r,y,b,o,g,p,l,i -- Red, Yellow, Blue, Orange, Green, Purple, oLive, pInk
t -- Transparent is much trickier so I usually leave it for a while
The colours are states. The initial state is red.

Here's a simple example.
444b>4r44b>4r44b>

Chunks

Chunking code can help understand patterns.
[ ] -- makes a chunk of code
[444b>]  -- makes the three squares a chunk
Chunking is done automatically when you cut and paste (which are also single character instructions, x and v)
4r44b>xvvvv  -- makes an outline of a 4x4 square.
This helps introduce the concept of repetition.

Instead of using "x" to start again, you can to clear things, "c" , to start fresh without moving putting a copy to the clipboard. If you want to completely restart, "q" clears the clipboard as well.

Other regular polygons

3,5,6,7,8, (9,0,1,2) -- triangle, pentagon, hexagon, heptagon, octagon
( not in the interface nonagon, decagon, hendecagon, dodecagon)
These polygons allow for much more interesting patterns. A subtle aspect comes from the introduction of odd sided polygons--what is the first active side? Here the language has a right-hand bias. Whereas 444444 makes a straight line, 5555555 curves to the right.
4o5bxvvvvvvvvvv -- makes a nice colourful loop of squares and pentagons
 (notice the lack of < or >)

Try to link the code to the picture.
4o5bx  -- then paste it one at a time until you connect up (10 v) then add
>x  -- then paste the loop 5 times.

Exercises

See if you can make these. (try to use cut & paste)