The Polygon Intersector Applet


How to use the applet:

  1. It takes a little while to get the applet user interface loaded; expect about 10  seconds if you are located in a school lab near University of Montreal; if you are using a modem, it will of course take a little longer. It shouldn't  go over 30 seconds (it's an 85Kb download).
  2. On some viewers (such as netscape), the java.awt.MediaTracker is a bit broken. As a result, the very first time a vertex of  a polygon should appear, it may take some time to display (2-5 seconds; it's another 400 bytes download).
  3. Draw the polygons in CLOCKWISE order. The user interface will not let you draw something that is not convex or is not in clockwise order.  Try it and you'll see.
  4. When in insert mode, the vertex to be inserted must be next to the last vertex inserted, in clockwise order. I haven't implemented inserts at arbitrary points on the polygon.
  5. Resizing the window will give you extra precision, not extra space.
  6. The source code of the applet is available  here  (tar.gz format).  The javadoc-generated documentation can be found  here. It is rather terse, but it is still useful as a reference while reading the source code..


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