PPT Slide
Kangaroo hops from a triple clef icon which activates a program for playing 3-part canons, to an iicon that allows musical data to be viewed in traditional music notation and then to an ice cube, where the squence of hops is “frozen” so that it can be referred to by a single symbol. An icon can represent a hierarchy of programming structures. The triple clef “expands” into the loop shown below it; the loop is executed once, launching (at intervals of 4 measures) the three birds that perform the canon. The sequence of instructions embodied in each bird is shown to the right of the loop. If a bird flying along the score is at a note, it sounds the note; otherwise, if it is at the end of the score, it returns to the beginning. The canon itself was composed by Lanier with the aid of the illustrated Mandala program.-- Sci. Am. Page 6.