TetrisSaver

TetrisSaver is a very simple screen saver for OSX Beta, and now for 10.3. It emulates a game of Tetris, but with the computer working out where each shape should go.

To use TetrisSaver, download, decompress if your web browser does not do this for you, and double click the .saver item to install it.

Notes:

Well, after a bit of a break, TetrisSaver is back and working for versions of OS X other than the beta. The new version doesn't work on 10.2, sorry. Source code's been updated to this version, bottom comment still applies.

Original Notes:

There are some problems with screens at different bit depths. If you run your monitor at 8 or 16 bits (255 or thousands of colours) then use the top download. If you run at 24 bit (millions of colours) then use the second download.
I've taken bits of code from several other screensaver programs. The blue background is taken from 'Paper Airplanes', supplied by Eric Peyton (who also gave me some OpenGL help - thanks!). However, the tetris code is all my own.
MacOS X does not accelerate OpenGL on some graphics cards. It does not on mine. TetrisSaver will probably go quite slowly unless you've got hardware acceleration.
The shape placement algorithm is not very clever. It tries to avoid creating holes, and to keep the top layer of dropped shapes fairly flat. There's room for improvement here.
The source code is available for anyone to change, improve etc. I'd prefer it if any improvements were made available under the same conditions but ultimately that is your choice.