Setting preferences

The Preferences dialog

You can change the size of new soups with the popup menu. Note that in soups larger than 64k, creatures cannot address the whole soup. See the section on relative addressing for more details.

The 'Seed soup with a new ancestor' places the original 80-instruction ancestor into new soups. However, to create a new, empty soup without changing preferences, simply hold down the option key while choosing 'New' from the file menu. This creates an empty soup, with all mutation rates set to zero, which is useful for experimenting with new creatures.

The 'Instructions per time slice' value is the number of instructions that a creature can execute during one time slice. Smaller values mean that creatures approximate more closely to running in parallel (i.e. they each get a small time slice in turn), but slows execution speed. 10 seems like a good compromise figure.

The popup menu allows you to specify which program you want to use to open data files saved by MacTierra. (If there are others you'd like to see on this menu, let me know).

There are also a couple of options to tell MacTierra to automatically save the soup while it is running. Check 'Auto-save soups' to enable this. The 'New file for each save' options causes each saved soup to be created in a new file. This might be useful it you want to trace the evolution of the soup over a series of stages.

The Preferences file

MacTierra checks the version number of the preferences file when it starts up, and will warn you if this is out of date. If this is the case, then you should delete this file and let MacTierra build a new one.