II. Visualization

"You do not understand anything until you understand it in more than one way."

--Marvin Minsky

Authors have frequently tried to explain and visualize complex concepts and ideas by other means than the printed word. The proverb "a picture is worth more than a thousand words" holds still true also in the multimedia age. Additionally, the computer gives us more sophisticated ways to visualize complex facts, concepts, and algorithms. Scientific visualization, program visualization, and algorithm animation are well know concepts in computer science, although their use only slowly starts to emerge outside of the academic community. Part II describes one aspect of scientific visualization, namely algorithm animation, that has been around for some decades, but has only rarely been used apart from the computer science domain. Using algorithm animation at its best offers a prospective multimedia author a unique way to explain complex concepts that are very hard to convey by other means.

After a short survey of algorithm animation, part II focuses on the Animated Algorithms project, a large-scale attempt to create an educational hypermedia product based on the textbook "Introduction to Algorithms" by Tom Cormen, Charles Leiserson , and Ronald Rivest [Cor90]. Animated Algorithms consists of three interactive components: A hypertext version of the book itself, animations of the most important algorithms, and movies explaining the use of the hypertext interface and the animations. On the example of Animated Algorithms the book illustrates design criteria, user interface issues, and the creation process for the production of algorithm animations. Special emphasis is put on the educational aspects. Later chapters of part II introduce advanced concepts of creating algorithm animations by using an animation specific scripting language and of animating proofs of algorithms.