The design was inspired by a blog on Fronkonstin: Experiments in R. I modified the code a little bit, so that the output is generated by Peter de Jong Attractors instead of Clifford Attractors.

The definitive expressions of Peter de Jong Attractors are shown below:

$$ \begin{aligned} x_{n+1} &= \sin(a \cdot y_n) - \cos(b \cdot x_n) \cr y_{n+1} &= \sin(c \cdot x_n) - \cos(d \cdot y_n) \end{aligned} $$

Codes:

The output looks really pretty good, like a basket. You can visit this link for more examples and detailed parameters.