Some embodiments of the invention provide a method for presenting computer-generated characters. The method defines several frames for a character and sequentially presents the frames. Each frame depicts a particular representation of the character. Also, at least two of the frames provide different representations of the character. Some embodiments provide a method for applying effects to computer-generated characters. This method applies an effect to the computer-generated characters by first generating an effect script. It then selects the generated effect script to apply to the computer-generated characters.