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Computer Graphics is fun - even if Java Applets are Old Hat

Archive - Originally posted on "The Horse's Mouth" - 2010-11-13 10:47:21 - Graham Ellis

Applets - small applications which include a Graphic User Interface in them - are where Java started ... but they didn't grow as much as other uses of Java and these days they're something of a specialist interest - great for some Intranet applications, but not so common / practical on applications that will reach a wider Internet audience. The reasons are (a) that people don't like risking the download of a JVM to run in their browser (though it is just as safe as ActiveX and / or Flash) and (b) because of those other two technologies that I just mentioned; Flash is rather good, and ActiveX has achieved a prominent position with help in various ways like being shipped as standard with common operating systems / browsers.

So a course that "majors" on Applets is either very old ... or very specialised.

But graphics is such fun! And if encourages on a Java course, I'll overview how to use Java within an applet, and pull up some code sample. I've a handful of recent ones, and a whole library of history.

This example shows the basics - a couple of buttons, and something happens (lines drawn, numbers added) when the mouse button is clicked. See the HTML frame that you'll need [here] and the java applet source [here]


And this is quite a sophisticated (but simple) demonstration of double buffering in Java - you can drag the corners of the box around and the shapes around the outside willall change to reflect this. In order to avoid a flickering display, the new graphic is always generated in the background, and the copied en masse to the frame buffer that's being displayed.


My background is computer graphics - I love playing with this sort of thing, so please ask me if you want to learn about Graphics in Java, or Python, or PHP, or Lua ... you'll find examples of all sorts of things on the site!