Algorithm 483 Masked Three-Dimensional Plot Program with Rotations [J6].

This article discusses various issues related to the three-dimensional plot programming and algorithm 483. PLOT3D will accept three-dimensional data in various forms, rotate it in three-space, and plot the projection of the resulting figure onto the x-y plane. Those lines or portions of lines that should be hidden by previous lines are masked. Each call to PLOT3D causes one line to be plotted. A line consists of a sequence of points in three-space that will be connected using linear interpolation between adjacent points. This sequence of points is specified by three sequences of real numbers, the x, y, and z components of each point. Each of these sequences of real numbers can be specified either as being equally spaced, and therefore denoted by an initial value and an increment, or as being contained in a real array. PLOT3D attempts to minimize plotter movement by beginning at the alternate end of successive lines. A more detailed description of the parameters is contained in the comments at the beginning of the program listing. This routine was developed at the Applied Research Laboratories on their Control Data Corp. 3200 computer system.