Down to the nitty griddy

Grids are a game development essential. As we saw in the previous chapter, a classic board game like Battleship is set up in a grid. So are about 50 other board games I can think of off the top of my head: Connect Four, Guess Who, Stratego, chess, tic-tac-toe, Clue, checkers, chutes n' ladders, go, slider puzzles, and so on—it's an absolutely huge list. Add to that the slew of digital games that use a grid layout: MineSweeper, Tetris, Bejewelled, Puzzle League, Bomberman, Dr. Mario, Breakout. And lest you think that only 2D games use grids, consider 3D turn-based strategy games—the action takes place on a grid! Grids are used in inventory screens, in image galleries, and on level select screens. A* (A-star), a popular method for moving characters around obstacles on the screen ("pathfinding"), can also use grids. In fact, your entire computer display is a grid of square pixels.

Mastering the grid is key to mastering game development. You'll use grids again and again...