Quickstart to GA Internals

Introduction

This article outlines the fundamental process.

As a simple outline, all of the program is in one single file. There are various main() functions for test modes (don't worry about them right now) but the actual main() requires -DRUN_MODE compile flag. This function does the following:

• Set up a new cellular grid.
• Iterate a fixed number of cycles.
• Pick pairs of nearby cells.
• Evaluate an interaction between pairs.
• Save frames as PNM images every so often.

That's about the heart of it.

Quickstart to GA Internals

• struct cell_S contains the data held in each cell.
• function point_select() picks a random pair of nearby cells.
• function hamming32() calculates Hamming distance.
• function tolfunc() calculates the parametric tolerance (based on Hamming distance).
• function outcome() calculates the outcome of the Prisoner's Dilemma.
• function transaction() is the full interaction between the cells.

Quickstart to GA Internals

• struct col_item_S contains a single item mapping from Hamming space to RGB colour space.
• array col_item_T col_items[] is a list of standard colours and bitmaps.
• function get_colour() converts from Hamming space to RGB colour space (using col_items).
• function output_frame() dumps the whole cell grid to an image file (with colour translation, etc).