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Value-Based Animations Many visual effects can be achieved by continuously changing values associated with a game entity, such as the following: • A movement effect can be created by changing the position coordinate values. • A spinning effect can be created by changing the rotation value. • A growing or shrinking effect can be created by changing the scale factors. • A color-cycling effect can be created by changing the color red/green/blue component values. • A fading in/out effect can be created by changing the alpha (transparency) value.

You will use a BaseActor for the background floor tile image, and another for the title graphic, both of which need to be copied to the assets folder. You’ll use a Label to create the instruction text, and since it is an extension of the Actor class, you can and will add a repeating sequence of actions to give the text a pulsing effect. addActor( instructions ); In the render method, you’ll check to see whether the user is pressing the S key, in which case you’ll use the setScreen method of the Game class to switch the Screen to a CheeseLevel instance, which is where the game is played.

A few other fundamental differences between the Sprite and Actor classes should be mentioned here. First, in addition to a draw method, the Actor class has an act method, which can serve as a form of an update method for the Actor. Second, the Actor class was designed to be used in concert with a class called Stage (that you will be using in the near future), which stores a list of Actor instances and contains methods (named act and draw) that call the act and draw methods of every actor that has been added to it.