cl-value-noise has the only function value-noise:value-noise to
generate one-, two- or three-dimensional value noise.
value-noise(x y z &key (octaves 5) (seed 1))Generate value noise in the range \([0, 1]\).
x, y and
z must be non-negative single-float values. octaves
specifies the number of high-frequency components in the
noise. seed is used to generate a unique examplar of noise.