“Models of light reflection for computer synthesized pictures” by Blinn

  • ©James (Jim) F. Blinn

Conference:


Type:


Title:

    Models of light reflection for computer synthesized pictures

Presenter(s)/Author(s):



Abstract:


    In the production of computer generated pictures of three dimensional objects, one stage of the calculation is the determination of the intensity of a given object once its visibility has been established. This is typically done by modelling the surface as a perfect diffuser, sometimes with a specular component added for the simulation of hilights. This paper presents a more accurate function for the generation of hilights which is based on some experimental measurements of how light reflects from real surfaces. It differs from previous models in that the intensity of the hilight changes with the direction of the light source. Also the position and shape of the hilights is somewhat different from that generated by simpler models. Finally, the hilight function generates different results when simulating metallic vs. nonmetallic surfaces. Many of the effects so generated are somewhat subtle and are apparent only during movie sequences. Some representative still frames from such movies are included.

References:


    1. Blinn, J. F. and Newell, M. E. Texture and reflection incomputer generated images. Comm ACM 19, 10(Oct 1976), 542-547
    2. Bui-Tuong Phong. Illumination for computer generated images. Comm ACM 18, 6(June 1975) 311-317
    3. Catmull, E. A. Computer display of curved surfaces. Proc. Conf. on Comptr. Graphics. May 1975 (IEEE Cat. No. 75CH0981-1C)11-17
    4. Gilpin, F. H. Effect of the variation of the incident angle on the coefficient of diffused reflection. Trans. Illum. Eng. Soc. Vol 5, 1910 854-873
    5. Middleton, W. E. K. and Mungall, A. G. The luminous directional reflectance of snow. J. Opt. Soc. Am. 42, 8(Aug 1952) 572-579
    6. Torrance, K. E. and Sparrow, E. M. Polarization, directional distribution, and off-specular peak phenomena in light reflected from roughened surfaces. J. Opt. Soc. Am. 56, 7(Jul 1966) 916-925
    7. Torrance, K. E. and Sparrow, E. M. Theory for off-specular reflection from roughened surfaces. J. Opt. Soc. Am. 57, 9(Sep 1967) 1105-1114
    8. Trowbridge, T. S. and Reitz, K. P. Average irregularity representation of a roughened surface for ray reflection. J. Opt. Soc. Am. 65, 1975) 531-536


ACM Digital Library Publication:



Overview Page: