A tool to create the convex hull of a set of points using the Graham scan algorithm.
A set of points like [(-2, -1), (-2, 0), (0, 0), (1, 2), (2, -1), (2, 3)] would look like this in a coordinate system:
And the convex hull of these points is a shape formed by the points [(-2, -1), (2, -1), (2, 3), (-2, 0)] and looks like this:
A dialogue with the shell to calculate the above convex hull using the Graham Scan algorithm looks like this:
gs> add 0 0
gs> add -2 0
gs> add 2 -1
gs> add 1 2
gs> add 2 3
gs> add -2 -1
gs> print
[(-2, -1), (-2, 0), (0, 0), (1, 2), (2, -1), (2, 3)]
gs> convex
[(-2, -1), (2, -1), (2, 3), (-2, 0)]
For more details on how the Graham Scan works you can visit the explaination provided on the Wikipedia page wikipedia.org/wiki/Graham_scan