%0 electronic Article
%A Doh, Jeong-In
%E Chwa, Kyung-Yong
%D 1988
%G English
%@ 1432-2315
%T Visibility problems for orthogonal objects in two-or three-dimensions
%J The Visual Computer : International Journal of Computer Graphics
%V 4
%N 2
%P 84-97
%U http://dx.doi.org/10.1007/BF01905560
%K OriginalPaper
%K Visibility
%K Hidden-line elimination
%K Orthogonal objects
%K Computational geometry
%X Let P be a set of l points in 3-space, and let F be a set of m opaque rectangular faces in 3-space with sides parallel to x- or y-axis. We present an O(n log n) time and O(n) space algorithm for determining all points in P which are visible from a viewpoint at (0,0,∞), where n=l+m. We also present an O(n log n+k) time and O(n) space algorithm for the hidden-line elimination problem for the orthogonal polyhedra together with a viewpoint at (0,0,∞), where n is the number of vertices of the polyhedra and k is the number of edge intersections in the projection plane.