Have you seen Avatar, directed by James Cameron (Twentieth Century Fox France, 2010)? This film, like Shrek (Andrew Adamson and Vicky Jenson, 2001), Wall-E (Andrew Stanton, 2008), Frozen (Chris Buck and Jennifer Lee, 2013), and so many others, features computer animation. When you think about it, this means that someone devised a series of instructions for a computer to execute in order to produce the finished result.
This is no mere matter of getting a computer to draw a chair or a table! It has to depict a natural landscape, complete with terrain and moving characters. Clearly, specifying the position of every colored pixel frame by frame is out of the question: it would be far too laborious and unmanageable, both in terms of memory and processing time. We therefore need a trick that saves computation time; otherwise, no computer will be able to complete the task.
The fractal nature of the world
---------------------------
To begin with, it seems simpler to consider an inanimate object—for example, a table. This piece of furniture is clearly defined: four legs, a vanishing point, a horizontal top at a certain height, and a little shadow are enough to depict it. But what if we take a landscape like the one opposite? It is so complex that we do not even know where to begin!
