I was recommended on StackOverflow to ask this question here: for me it's dataviz question, but perhaps it's more algorithmic in nature.
I have an ordered set of points in 2D, and would like to join them using some sort of spline to form a closed loop that does not intersect itself. This is, in fact, a single contour line, and I have additional sets of points marking out further contour lines that should be sequentially nested inside each other. Do any dataviz procedures exist to do this without intersection? For instance, take the 23 black points in this picture as the outer contour and the 12 blue points as an inner contour.
I would want to join them vaguely like this:
If it helps, I'll probably be trying to visualise this in R.