This is a JavaScript implementation of the CONREC contouring algorithm, which operates on a grid of z-values.
If no contour-drawing function is specified, it builds a list of contour vectors that can be accessed via .contourList().
Example:
var data = [[0, 1, 0], [1, 2, 1], [0, 1, 0]];
var c = new Conrec;
c.contour(data, 0, 2, 0, 2, [1, 2, 3], [1, 2, 3], 3, [0, 1, 2]);
// c.contours will now contain vectors in the form of doubly-linked lists.
// c.contourList() will return an array of vectors in the form of arrays.