Rapid prototyping with Cocos2d-x
The idea behind this is to create sprites as placeholders for your game elements as quickly as possible, so you can test your game ideas and refine them. Every game in this book was initially developed in the way I'm about to show you, with simple rectangles in place of textured sprites.
The technique shown here allows you to create rectangles of any size and of any color to be used in your game logic: