Re: Drawing polygons and keeping a list of them...

FROM : Thomas Davie
DATE : Mon Apr 25 20:11:22 2005

> What container do you recommend I use to:
>
> a) hold the points of each polygon.
> b) hold the list of polygons.

That's your own design decision, I personally would use my own class 
for a polygon and an NSArray for the list of them :).

> 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.

The way this tends to be done in most apps that I know of is the user 
clicking on the start point of the polygon again (usually with a few 
pixels tolerance for the inaccuracy of a mouse).

Bob