Rectangle and Box Visibility Graphs in 3D
نویسندگان
چکیده
We discuss rectangle and box visibility representations of graphs in 3-dimensional space. In these representations, vertices are represented by axis-aligned disjoint rectangles or boxes. Two vertices are adjacent if and only if their corresponding boxes see each other along a small axis-parallel cylinder. We concentrate on lower and upper bounds for the size of the largest complete graph that can be represented. In particular, we examine these bounds under certain restrictions: What can be said if we may only use boxes of a limited number of shapes? Some of the results presented are as follows: • There is a representation of K% by unit boxes. • There is no representation of K\Q by unit boxes. • There is a representation of /C56, using 6 different box shapes. • There is no representation of if i84 by general boxes. A special case arises for rectangle visibility graphs, where no two boxes can see each other in the xor ^-directions, which means that the boxes have to see each other in z-parallel direction. This special case has been considered before; we give further results, dealing with the aspects arising from limits on the number of shapes.
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ورودعنوان ژورنال:
- Int. J. Comput. Geometry Appl.
دوره 9 شماره
صفحات -
تاریخ انتشار 1999