NASA Center: Johnson Space Center
Public Release Year: 1990
Reference Number: JSC-SO-46
Category: Computer Technology
Origin: NASA Computer Aided Design Technology
A mathematician, David R. Hedgley, Jr. developed a computer program that considers whether a line in a graphic model of a three-dimensional object should or should not be visible. Known as the Hidden Line Computer Code, the program automatically removes superfluous lines and displays an object from a specific viewpoint, just as the human eye would see it. An example of how one company uses the program is the experience of Birdair which specializes in production of fabric skylights and stadium covers. The fabric called SHEERFILL is a Teflon coated fiberglass material developed in cooperation with DuPont Company. SHEERFILL glazed structures are either tension structures or air-supported tension structures. Both are formed by patterned fabric sheets supported by a steel or aluminum frame or cable network. Birdair uses the Hidden Line Computer Code, to illustrate a prospective structure to an architect or owner. The program generates a three-dimensional perspective with the hidden lines removed. This program is still used by Birdair and continues to be commercially available to the public.
Page Number in Published book: 94-95
Manufacturer: Birdair, Inc.