On The Understanding Of Line Drawings
A. Fiumicelli, Vincent Torre · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1987
The understanding of line drawings of scenes of Legoland (a blocks world with object boundaries belonging to only three directions) can be obtained by exploiting properties of planar surfaces and of perspective projection. The normal versors of pannels are first recovered, using the rule of maximal visibility and properties of vanishing points and of horizon lines. The usual labelling of edges can be derived from the knowledge of normal versors.