Whereas the storyboard approach allows one to lay out the links between objects, and emphasizes how the user moves through the work, an object-oriented approach focuses on the what can be done to and by an object. An object-oriented approach emphasizes classifying objects and identifying the attributes of those objects. Take, for example, a program written by Laurie Spiegel called Music Mouse. Music Mouse is a virtual musical instrument that is played by moving and clicking the mouse in an area on the screen. Moving the mouse causes musical pitches to be played selected according to a chosen theme. Certain keys on the keyboard modify aspects of the pitches such as timbre, scale, and pitch combinations. There are no links or logical chunks to move between. The interactive storyboard model is not appropriate for describing Music Mouse. The object oriented model, however, allows us to effectively describe Music Mouse.

Image linked to from http://www.retiary.org/ls/programs.html

As the mouse is moved in the active area, sounds are created based on a vast array of options and settings available. For this illustration, I will focus on the playing space actions that produce the sound. The playing space is a square area on the screen that responds to mouse actions. The mouse actions it responds to are: clicking and moving. When the mouse is moved, the playing space responds by creating a harmonization based on the mouse position. That harmonization is then realized by the chosen synthesizer. When the mouse button is clicked and held down, no sound is triggered when the mouse is moved. When the mouse button is released, sound can be triggered again. The two types of mouse actions need to be aware of their location in the playing space, and they need to know what to do when their action or actions occur. A Mouse Action in general might look like this:

Specific Mouse Actions, with specific methods:

The different behaviour of the two actions would be realized in the different methods. In the on move method, every time the mouse moves, a message is sent to the Playing Space object. In the on click method, a message is to the Playing Space when the mouse button is pressed down and up.

The Playing Space object responds by sending a message to its current Harmonizer.

The Harmonizer then responds by sending a number of play note messages to the active Synthesizer.

The object-oriented approach makes explicit what objects are present, what the objects do, and how the objects interact. This descriptive technique is very useful for describing interactive new media objects that are changing continuously.