This blog has relocated to https://coolbutuseless.github.ioand associated packages are now hosted at

29 April 2018


Messing around with chull

As mentioned yesterday, I’m using chull() to create some stuff.

The basic scheme is:

  • Generate a large number of points somehow
  • Repeat the following until done:
    • Take a small subset of the points
    • Draw the convex hull around them.

Extra filtering was done to reject some of the generated convex hulls, i.e.

  • Reject those with a large area, as I wanted to use smaller, local hulls
  • Reject those with “bad” circularity. i.e. when the ratio of convex hull area to bounding box area was too low

Here’s what happens when a recognizable image is used as a point source.

Creation of Mona Lisa image