Next comes the player controls. Chopper Command had a pretty unique way of handling change of direction and it was one of the main challenges in the game play, so I took special care in replicating it.
Continuing on with the port of Chopper Command, I picked the radar tile to be the next thing to be implemented. I decided to use composition and make each GameTile contain an instance of a RadarTile. When the main loop updates the GameTile it in turns updates its own RadarTile.
So as I mentioned in my previous post, the game contains 5 “screens” scrolling across… well, the screen. I called these Game Tiles. Each contains 3 enemies and 3 trucks.
The enemies move around the tile, constrained by 3 rectangle boundaries, so that one enemy never flies into the path of another.