3/4/2010

No self-respecting language is complete of course unless it's capable of
handling the following exercise ...

Write the "Game of Life" in tiny-c.




(Well, our latest member (that would be Bob Hardhacker, I mean, Tom
Veile) might disagree and say the assignment should be "Write a program
in tiny-c that generates its own source code" which, I must admit,
occured to me as a possible March challenge, but I decided that was too
arcane to ask. Maybe some other day ...)

You say you haven't heard of "The Game of Life?" You haven't "wasted"
hours coding, watching, thinking about John Conway's masterpiece? Where
have you been?!

This may be dangerous but I'm going to leave the spec's for this one
pretty open-ended. Be creative and set your own limits. The most
important requirement of course is that you follow the rules:

In an n x n grid ...

1. an occupied cell "lives" and will appear in the "next generation" if
it has 2 or 3 "neighbors" (i.e. occupied cells in its neighborhood)

2. an occupied cell "dies" and does not appear in the "next generation"
if it has 0, 1, 4 or more "neighbors" (loneliness / overcrowding rule)

3. there is a "birth" in an unoccupied cell and will appear in the "next
generation" if this cell has exactly 3 "neighbors."

One new thing you will have to investigate in order to do this
assignment is how to position the cursor in tiny-c programs. The system
library has functions that do this. In addition, if you're using the PC
interpreter (i.e. not the Linux interpreter) you will need to run
ANSI.COM (or equivalent) before you run the interpreter to provide
support for the cursor positioning calls.

Here's a program which uses cursor positioning (and a page which shows a
sample run).

meteor.tc meteor.html

References:

Java applet Wikipedia

Spoiler:

tiny-c life program

Notes:

The above solution has a "menu" system which looks like so:

b/g/l/f/m/a/s/r/w/p/q/? 

The help pick (?) is supported by the code below.

  if (b=='?') [
   pl"";pl "";ps "(b)link (g)lide (l)ine (f)ill (m)anual"
   pl "r(a)ndom (s)peed (r)ead (w)rite (p)lay (q)uit"
   ]

It has a few bells and whistles (quite literally). A video capture of a
run may be seen here:

http://www.primepuzzle.com/tc/life-glider.gif