“ATOMLLL: ATOMS with shading and highlights” by Max

  • ©Nelson L. Max




    ATOMLLL: ATOMS with shading and highlights



    The ATOMS program, written at Bell Telephone Laboratory, is capable of determining the visible portions of a scene consisting of interpenetrating spheres and cylinders, put together to represent “space-filling” or “ball-and-stick” molecular models. The Lawrence Livermore Laboratory version contains enhancements to add shading and highlights, and to render the spheres on film as ellipses, so they will appear round when projected in various wide-screen formats. The visible parts of each sphere or cylinder are shaded by a minicomputer controlling the film recorder, thus releasing the main computer from transferring the millions of intensity values for each frame. The minicomputer is microprogrammed with an efficient algorithm for the intensities, which uses the color look-up tables in the film recorder to store the reflectance as a function of angle of incidence.


    1. Blinn, James F. Models of light reflection for computer synthesized pictures. Computer Graphics Vol. 11, no. 2 (1977), pp. 192-198.
    2. Bresenham, J. E. An incremental algorithm for digital display of circular arcs. Communications of the ACM Vol 20, no. 2 (1977), pp. 100-106.
    3. IMAX. Promotion brochure, November 1977, available from IMAX Systems Corporation, P.O. Box 224 Cambridge, Ontario Canada N1R5T8.
    4. OMNIMAX. Promotion brochure, September 1977 available from IMAX Systems Corporation, ibid.
    5. Knowlton, Ken and Cherry, Lorinda. ATOMS, a three-d opaque molecule system. Computers and Chemistry Vol. 1, no. 3 (1977) pp. 161-166.
    6. Max, Nelson. ATOMLLL – a three-d opaque molecule system, Lawrence Livermore Laboratory version, UCRL-52645, Lawrence Livermore Laboratory 1979.
    7. Max, Nelson. DNA with ethidium. 5 minute color silent computer animated film, available on loan from the author.
    8. Porter, Thomas. Spherical shading. Computer Graphics Vol. 12, no. 3 (1978) pp. 282-285.
    9. Staudhammer, John. On display of space filling atomic models in real-time. Computer Graphics Vol. 12, no. 3 (1978) pp. 167-172.

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