C4. CLOUDS

Very realistic clouds can be created using a fractal construction. We begin with the construction used to construct a mountain landscape, but instead of assigning a height to various points, we assign a colour. For example with the (real!) cloud shown above, we would assign a range of colours between white and sky blue or dark grey. The result is a covering of a region of the plane which looks remarkably cloud-like.

Fractals for the Classroom Part One, Peitgen, H–O, Jürgens, H., Saupe, D. p429 (Springer 1992)

http://www.stormeffects.com/2002_monsoon_images.htm