[Repast-developer] Conway's life and few other things

[Nick C. <vze...@ve...>]

Hi,

I wanted to add a demo model that used SimpleModel as a base class to
the RePast distribution. So, I implemented Conway's life. SimpleModel is
really suited for this as the same thing happens every tick and the
model divides up nicely into an "execution" and post-execution phase. 

The canonical implementation takes place on an "infinite" space, but I
used a torus. You still get gliders, guns, etc., but obviously the
longer term dynamics are different. If there's time, I'll do an
"infinite" space version, if only so I can muck up the space package a
bit more :). Its in CVS so feel free to update and take a look.

As part of implementing Life, I made some important changes to
ListPropertyDescriptor and the reflector package in general. For those
that don't know the reflector package handles probing, that is, the
display of an object's properties and the gui manipulation of them.
Previously, the gui widgets responsible for editing the properties
returned the edited value as String. This String was then transformed
appropriately and passed as the argument to some set method. This was
fine for primitives and Strings, but made it difficult to "edit"
objects. I changed the Widget interface to return an Object rather than
a String and added some new code to invoke the set method with an Object
argument. This impacts all areas of probing. I ran some tests, and
everything seems okay, but let me know if there are any problems.

The point of doing this was to allow named Objects in
ListPropertyDescriptors. In the case of Life, the Objects are setup
objects for initializing the grid. You chose the name of the initial
grid pattern and this sets the setup object. Then this SetUp object's
setup method gets called when the model is setup. (Whew! That's a lot of
setup).

Lastly, in making the evolver distribution last week, I moved some stuff
out of the rscript package. The result is that a fresh update and
compile from scratch from CVS won't work. I'll remove the rscript
directory tomorrow, and that should fix the problem.

Nick

-- 
Nick Collier 
Social Science Research Computing
University of Chicago 
http://repast.sourceforge.net