Geometry Boost List: [ggl] Question about blogpost

Subject: [ggl] Question about blogpost
From: Rykov Denis (rykovd)
Date: 2010-04-16 22:16:29

Hi. I've read blogpost
http://barendgehrels.blogspot.com/2010/02/polygon-above-can-be-represented-in-two.html
and have one question.

"This green polygon above can be represented in two different ways:

    * as one sequence of points, so one ring, which is self-touching
in point (2,2)
    * as an exterior ring ring, and an interior ring, both rings touch
in point (2,2)
"

Why touch point is calling as (2,2), why not (1,2) as representing in picture?