Hidden line removal
Hidden line removal is an extension of wireframe rendering where lines (or segments of lines) covered by surfaces are not drawn. This is not the same as hidden face removal since this involves depth and occlusion while the other involves normals. An commonly used algorithm to implement it is Arthur Appel's algorithm (developed at IBM in the late 1960's). This algorithms works by propagating the visibility from a segment with a known visibility to a segment whose visibility is yet to be determined. Certain pathelogical cases exist in making this algorithm difficult to implement, those cases are (i) verticies on edges and (ii) edges on verticies and (iii) edges on edges. James Blinn published a paper on this problem.
See http://wheger.tripod.com/vhl/vhl.htm for a further description and more citiations.
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