Drawing polygons and keeping a list of them...

FROM : Brian O'Brien
DATE : Mon Apr 25 20:06:20 2005

I am writing an application that will need to draw polygons on top of
images.
There may be multiple polygons on an image.

What container do you recommend I use to:

a) hold the points of each polygon.
b) hold the list of polygons.

Another question I have is more of a GUI nature than a programatic
one...

Every time a user clicks on the image a new point is added to the
current polygon.
How then should I 'close' the polygon?  Should the user press the
escape key or
right mouse button?  I need to know somehow that the user is finished
drawing this
polygon and is going on to draw the next polygon.


Thanks!
B.