10. Changing the Way Sprites Look and Behave

By its very nature, Scratch lends itself to the development of graphical applications that involve the manipulation of sprites. This includes taking actions that affect the appearance and behavior of both sprites and the stage background. Sprite and background appearance and behavior can be controlled using looks code blocks. Looks code blocks can be used to affect sprite appearance through the application of special effects, to make sprites visible or invisible as applications execute, and even to change sprite costumes and stage backgrounds. This chapter offers an in-depth overview of all of Scratch’s looks code blocks and will guide you through the creation of your next Scratch project, the Crazy Eight Ball game.

The major topics covered in this chapter include:

• Learning how to programmatically change a sprite’s costume

• Learning how to display text in speech and thought bubbles

• Discovering how to apply a range of special graphical effects to sprites

• Learning how to change a sprite’s size

• Making sprites appear and disappear during application execution

• Specifying how sprites that overlap one another should be displayed