This "script" is actually a script-fu logo script that has been converted
to perl. Instead of producing a logo from a text string (nice but rather
limited in the shapes you can create) it uses the drawable you specified
as the text shape. Any colour that the plug-in tries to use is ignored,
which allows you to create multi-colour text.
The drawable must have an alpha channel, and the shape of this channel
prescribes the shape of the logo. Most logos ignore any colour information
and instead use the shape only as a stencil, but some logo scripts do make
use of the text colour.
The original help for follows:
give text a speedy effect