Level up your programming skills while making fast-paced, arcade-style video games. Make enemy spaceships explode in balls of fire, and escape from a pit while dodging falling boulders. You'll use the fun and approachable Ruby programming language and the Gosu 2D game library, which makes making games a breeze. Gain the skills and techniques you need to bring your own video game ideas to life with moving images and thumping sounds. If you have a little experience programming in Ruby or another language, then you're ready to start making your own video games. In this book you'll learn concepts such as animation, keyboard and mouse movement, sounds and music, and physics as you build four exciting games. Your first game will test your reflexes as you try to click on a ruby that pops in and out of your screen. Learn how to draw images and text, and how to make objects move around the screen. You'll make a space-shooter where you defend your home base from a seemingly endless stream of enemies, as you discover how to use keyboard input, add music and sounds, an opening title screen, and scrolling end-credits.Next up: make a sliding number puzzle game where you'll learn to incorporate more complicated logic and user interaction into your game. Learn all about game physics as you build a game where a bold adventurer must climb out of a pit while dodging bouncing, spinning rocks. Finally, package up your games as Windows and Mac apps so you can share them with your friends. When you're done with this book, you'll have improved your programming skills, and you'll have all the tools you need to make your own arcade-style games. What You Need: You'll need a computer running Windows 7 or later, or Mac OS X 10.7 or later. All the other software you need is free, and the first chapter will get you up and running.