Smart screensavers: SETI and Electric Sheep

Smart screensavers: SETI@home / Electric Sheep

After last week’s assignments you should be ready to tackle a more complex application. Our test case will be a screensaver. What is the essential nature of the screensaver? Is it just pretty graphics, or could it be a medium for information?

Screensavers serve several functions:

  1. They save screens. Literally, they prevent phosphor burnout on CRT screens. On LCD screens they’re not quite so useful in this respect, since it’s healthier for the screen to power down than to stay on.
  2. They lighten up the office environment, and even entertain people with their endless animations.
  3. In a well-regulated office or school environment with little room for self-expression, having a special screensaver can be the equivalent of wearing a T-shirt with a band name on it. People customize their technology because it’s an expression of their identity.
  4. For more information on screensavers, see Wikipedia: Screensaver and Wikipedia: After Dark

Generative screensavers
To the frustration of many digital artists, screensavers have much in common with generative art. They often rely on some kind of ruleset to allow infinite animation and to avoid burning a single image into the screen because of repetition. Many classic screensavers use mathematical formulas like Beziers or Lissajous curves. But most screensavers are created by programmers, not designers, hence the bad reputation they have as cultural artifacts.

Smart screensavers
Recently, screensavers have gotten a whole lot smarter. The SETI@home screensaver is in reality a client for a distributed computing platform trying to find signs of intelligent life in outer space. Scott Draves’ Electric Sheep is also a distributed computing client, but it aims to create life rather than find it in space. By letting it run on your computer you’re taking part in a massive genetic algorithm aiming to produce interesting fractal animations.

Widgets: Apple

Widgets: Apple’s Dashboard and Yahoo Widgets

What about widgets?
Widgets are simple mini-applications that have been gaining in popularity since the introduction of Apple’s Dashboard. Many widgets are interactive, such as calculators or notepads. But others are information gathering devices, listening to RSS streams and other forms of online information and delivering it to the user. Could we mix our screensaver metaphor with the idea of a widget? What kind of information gathering device could a screensaver be?

Coding tips

  • If you’re making an animation that is meant to run forever without obvious repetition, you need some kind of random behavior. Consider using state counters with random intervals.
  • Even better: Try using noise() instead of random(). noise() produces a continuously fluctuating random value that can be used to produce smooth animations.
  • If you’re interested in doing information gathering, take a look at this blog post. It shows how to use the del.icio.us API with Processing. The openStream() function can also be used to read web pages from URLs, it’s not well-documented but there is an example here.