[dsp1234]

There is a link at the bottom of the page that links to https://medium.com/@williamngan/kubist-6ed1d8025806 which appears to be an explanation on how it works.

[lelandbatey]

In the demo there's also a second mode called "Cell" that seems reminiscent of sampling via Poisson Disc, which you can read more about in Mike Bostock's excellent "Visualizing Algorithms" post.[0]

[0] - http://bost.ocks.org/mike/algorithms/

[metaphorical]

Yep, both delaunay ("Triangle") and voronoi ("Cell") uses "best candidate algorithm" to distribute the points by default. It's similiar to poisson disc.

The "Analyze image" uses JSFeat to apply a computer vision algorithm (feature point detection) to add some "interesting" points based on the image.