The system evolves snow flakes and displays them falling down the screen of a www browser. The snow flakes are described by a Lindenmayer system grammar. As they flutter down the screen they are subject to random encounters and changes which may effect their grammar. In which case their new shape is drawn on the screen. The user can save pretty flakes.
Cookies are saved for a year.
Individuals are saved by clicking on them.
There is a nominal 5 second timeout (swait) before you can save it again.
If cookies are enabled, the cookie for that individual is updated.
Also pfeiffer_server.html will convert the genetic material to a string of hexadecimal digits (hexMe) and try and pass it across the network to harvest.
Note saving happens asynchronously, so an individual can be saved before or during rewriting and display of its picture .GIF file.
Passing the mouse cursor over an individual freezes it for about ten seconds (nominal, cwait).
Currently (July 2003) mutation is disabled and all new individuals
are created by crossover.
Just as when the program starts, a new .GIF file is down loaded from test.bat after every new individual chromosome is created.
Unlike save and restore (where the whole chromosome is passed over the network) the chromosome is parse by function cleanchrome in pfeiffer_server.html. This ensures it can be passed as plain text and also removes duff alleles from it.
test.bat invokes a modified version of http://www.246.dk lsys.perl
The L-system generates a series of drawing instructions which are passed to a modified version of http://www.246.dk/ pl2ppm.perl
W.B.Langdon cs.ucl.ac.uk 3 July 2003 ($Revision: 1.3 $ update 8 March 2004)