I am building an Android library with different kinds of progress views represented with curves. As you can see it in the gif below, I have used the following curves: Lemniscate of Bernoulli, Lemniscate of Gerono, Epitrochoid, Hypotrochoid, Heart curve and Cannabis curve (not in the gif) :).
Could you suggest some other curves that could be used in this library? Curve has to be periodic, and to have not that complicated parametric representation (so calculation would be fast).
