Occluded line removal for wireframe projection drawing

Wireframe doesn´t have the face information, so the occluded line of its projection drawing can´t be eliminated by existing methods for solid. In this paper, an efficient algorithm for eliminating occluded line from projection drawing of wireframe is presented. In projection drawing, whether there is an intersection of two lines is identified by bounding box and directed triangle. Further, the visibility of intersection lines can be determined by projection model. The occlusion matrix make up for the lost depth information during projection. The connected matrix of topological relationships between vertices is renewed by an occlusion matrix, and then a new connected matrix can defined a new projection drawing without occluded line. Test results show the high efficiency and stability of this algorithm.