XNA 4.0 Game Development by Example: Beginner's Guide

上QQ阅读APP看书，第一时间看更新

Time for action – play SquareChase!

Run your game by clicking on Start Debugging from the Debug menu or hit F5 on the keyboard.
Play an exciting game of SquareChase by holding down the mouse button and trying to catch the squares with your mouse cursor:

What just happened?

You just finished your first XNA game, that's what!

Granted it is not exactly the next blockbuster, but at only 33 lines of code, it implements a simple game mechanic, user input, score tracking and display, and clock-based timing. Not bad for a few minutes work.

Have a go hero

As simple as it is, here are a couple of enhancements you could make to SquareChase:

Vary the size of the square, making it smaller every few times the player catches one, until you reach a size of 10 pixels.
Start off with a higher setting for TimePerSquare and decrease it a little each time the player catches a square. (Hint: You'll need to remove the const declaration in front of TimePerSquare if you wish to change it at runtime).