No extra images is required form the server. The coding was messy, but it was a good project to learn about Java and netscape applet interaction. At the present time, all the needed images are generated and stored for future use. As a result, this applet run fast, but it can be a bit memory intensive. Fortunately, the size of the banner will always be small.
Improvements can be made to reduce the code size, so it load faster.
The encapsulation of the animation code needs improvment, so that the classes can be dynamically specified. Furthermore, if the user goes to other page, which runs the same applet, the applet executed as fresh and this new state will pass onto the previous applet. By using these characteristics, one can adjust the behavior of the applet depends on itself current environment. The NPAC banner applet is set up to exploit these characteristics. If the user click on applet while it is running, it stops.