This project is designed to be a super class or workshop of another
project that needs the user to choose a closed polygon.
There are three different types of polygon deformation implemented:
- Global: Click and drag a vertex to define it's new
location. All other vertices are moved following a discrete
tractrix.
- Local: Click and drag a vertex to define it's new
location. Just the two adjacent vertices are effected by this
deformation but the possible vertex positions are limited.
- Mirror: Click on the vertex that shall be mirrored.
The new vertex position is on the other side of the connecting line
of the adjacent vertices.
