Abstract: A method of modeling W-M fractal freeform surfaces by superposing W-M
fractals on parametric surfaces is proposed in this work. First, the significance of superposing
W-M fractals with parametric curves and surfaces is pointed out; then the importance of utilizing
arc-length parameterization for the superposing is described, and followed by our specific
algorithm with which the fractal simulation with freeform surfaces is achieved; at the last section,
an anisotropic approach for presenting freeform fractal surfaces is developed and with
demonstrated graphics simulation.

Key words: fractal, arc-length parameterization, parametric surfaces, anisotropic