ATOMS-a three-D opaque molecule system-for color pictures of space-filling or ball-and-stick models

Abstract ATOMS is a set of FORTRAN subroutines for depicting, in color, configurations of space-filling atoms and/or ball-and-stick models. Pictures are rendered as in traditional cartoon animation: solid monochrome areas separated by thin black lines. The user supplies x, y, z, radius, and color information for atoms; atom pairs, thickness and color for bonds, also parameters defining rules for viewing and picture drawing—including position and orientation of a hypothetical camera in user-defined space. The system is ideally suited for use with a filming unit that contains or is driven by a minicomputer. The host computer can then perform visibility calculations, yielding parameterized descriptions of visible patches of various colors; a routine resident in the mini generates the appropriate set of parallel vectors to fill solidly each patch area.