Some of realistic-looking greyscale renders are remarkably similar to those of Lyapunov fractal [1], which is 2D (and whose 3D-ish appearance is what makes it i

Some of realistic-looking greyscale renders are remarkably similar to those of Lyapunov fractal [1], which is 2D (and whose 3D-ish appearance is what makes it interesting). [1] http://en.wikipedia.org/wiki/Lyapunov_fractal http://en.wikipedia.org/wiki/Lyapunov_fractal