This is a (very) simple port of Tom Boutell's GD 1.2 graphics library.
Tom's original abstract on GD:
This is the gd gif-manipulating library, version 1.2. It was created to allow graphs, charts and the like to be generated on the fly for use on the World wide Web, but is useful for any application in which custom .GIFs are useful. It is not a paint program; it is a library.
Please read Tom's original README file for detailed information.