Essentially, you pass Delaunay.triangulate a list of vertices (which should be a bunch of two-element arrays, representing 2D Euclidean points), and it will return you a giant array, arranged in triplets, representing triangles by indices into the passed array. (This representation is a little bizarre, but object allocation is too slow for this library's original use case. Yes, really.)
Beware of using vertices that are too close to each other (say, within 0.01 on either axis): numerical precision issues may result, causing your mesh to be invalid. (If you encounter this, simply multiply each of your vertices' positions by a constant factor.)
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