Try to document TGear a bit, so people know what is commonly overridden, and what stuff is used for. Remove gtIceGun-specific values from TGear and abuse a couple of commonly abused members instead.
#! /usr/bin/sed -nf
s/^#define *FREETYPE_MAJOR *\([^ ][^ ]*\).*$/freetype_major="\1" ;/p
s/^#define *FREETYPE_MINOR *\([^ ][^ ]*\).*$/freetype_minor=".\1" ;/p
s/^#define *FREETYPE_PATCH *\([^ ][^ ]*\).*$/freetype_patch=".\1" ;/p