Given a set of (x, y, z) coordinates, how would I go about creating a contour map?
Would be nice to know how to implement in d3 but wouldn\'t mind trying to
It looks like this would be very easy with conrec.js. If you pass the data in the form that you have it, you can get a list of paths by calling .contourList() on the result. That you should be able to pass without modification to a d3 .data() call. All you should need to do is supply a path generator that maps the coordinates in the data to screen coordinates.
https://plot.ly/javascript/contour-plots/
Plotly.js: How to avoid overlapping contour lines?
How to apply plotly.js to an existing svg group <g> as target instead of applying it to a target <div> element?
https://github.com/d3/d3-plugins/blob/master/geom/contour/contour.js
And an example: http://bl.ocks.org/mbostock/4241134