It is important to be able to accurately and rapidly measure log diameter to efficiently and automatically process logs. This paper describes a computer graphic method to represent a three dimensional shape of a log. Basic cross-sectional data were obtained by passing logs, at a given speed, through a frame on which laser scanners had been installed. Images of the shape of the logs were then viewed on the computer screen where they could be manipulated such as changing the coordinates, zooming in or out, or rotating them.