Interpreting a 3D object from a rough 2D line drawing

Visualizing the third dimension while designing three-dimensional (3-D) objects is an awkward process in mechanical computer-aided-design (CAD) systems, given the current state of the art. The authors describe a computer system that automatically constructs the shape of a 3-D object from a single 2-D sketch. The method makes it convenient to create and manipulate 3-D objects, and is thus seen as an intelligent user interface for CAD and 3-D graphics applications. The proposed technique is built on well-known results in image analysis. These results are applied in conjunction with some perceptual rules to determine 3-D structure from a rough line drawing. The principles are illustrated by a computer implementation that works in a nontrivial object domain