[Gimp-developer] add a polygonal selection tool

[saulgoode at flashingtwelve.brickfilms.com]

Quoting Liam R E Quin <liam at holoweb.net>:

> It's not entirely true to say you had to have used paths from the start,
> since you can save the first selection to a channel, make the new one
> with paths, including an approximate, much larger outer rectangle,
> and then convert to selection and intersect with the saved selection.
>

GIMP 2.4 (RC2) allows you to add/subtract/intersect a path  
to/from/with the selection by using the SHIFT/CTRL/(SHIFT+CTRL) keys  
when you hit ENTER (or click on the "Create Selection from Path"  
button in the Tool Options).