Aliens Moving YAY

So in my last post I had one alien moving at once but couldn't figure out how to get them all moving together, but I have now and with a little help from some old Games book "Black art of Game Programming" I found that I needed a tracker (O.k something for each alien to track on screen) this would let each alien basically follow it backwards and forward.


This is a snippit of my code:

This is the set up for the Tracker:

This i s the tracker array for which the aliens will follow left and rgith: