Part 3 of Ralph Griswold's series on designing weave structures with Boolean operations describes an interactive program that automates the process. The program has a design laboratory, a drawdown editor and a Boolean operator array editor. The design laboratory combines two drawdowns (X and Y) with an operator array (A) to produce a result drawdown (Z). The article walks through the interface with screenshots, covering menus, dialogs, editing tools and the color palette for operators. It ends with the program's limitation to 32 x 32 drawdowns and operator arrays.