Fractal landscape generator, inspired by
• Mandelbrot, Stochastic Models for the Earth's Relief, the Shape and the Fractal Dimension of the Coastlines,
and the Number-Area Rule for Islands, Proc. Nat. Acad. Sci. USA 72 (10), 3825-3828 (1975).
• Mandelbrot, The Fractal Geometry of Nature, chapter 28.
• Peitgen, Jürgens, and Saupe, Chaos and Fractals: New Frontiers of Science, § 9.6.
