20. Game State Management

Normally, you don’t immediately start playing when a game application starts. For example, in the Jewel Jam game, you see a title screen before playing. More complicated games have menus for options, menus for selecting different levels, screens to display the high score after finishing a level, a menu to select different characters and attributes, and so on. In Jewel Jam, adding a title screen wasn’t that difficult, because the title screen itself had very little interaction. However, when you look at the example in the previous chapter, you can see that building a screen with a few options and controls can result in quite a lot of code. You can imagine that when you add more menus and screens to the game, it’s going to be a pain to manage which objects belong to which screen and when they should be drawn or updated.