Abstract
The quality of computer generated images of three-dimensional scenes depends on the shading technique used to paint the objects on the cathode-ray tube screen. The shading algorithm itself depends in part on the method for modeling the object, which also determines the hidden surface algorithm. The various methods of object modeling, shading, and hidden surface removal are thus strongly interconnected. Several shading techniques corresponding to different methods of object modeling and the related hidden surface algorithms are presented here. Human visual perception and the fundamental laws of optics are considered in the development of a shading rule that provides better quality and increased realism in generated images.
- 1 MAGI, Mathematical Applications Group Inc. 3-D simulated graphics. Datamation 14 (Feb. 1968), 69.Google Scholar
- 2 Comba, P.G. A procedure of detecting intersections of threedimensional objects. Rep. 39,020, IBM New York Scientific Center, Jan. 1967.Google Scholar
- 3 Weiss, R.A. BE VISION, a package of IBM 7090 FORTRAN programs to draw orthographic views of combinations of plane and quadric surfaces. J. ACM 13, 2 (Apr. 1966), 194-204. Google ScholarDigital Library
- 4 Mahl, R. Visible surface algorithm for quadric patches. IEEE Trans. C-21, (Jan. 1972), 1-4.Google Scholar
- 5 Catmull, E.E. A subdivision algorithm for computer display of curved surfaces. Ph.D th., Dep. of Comput. Sci., U. of Utah. Google ScholarDigital Library
- 6 Sutherland, I.E., Sproull, R.F., and Schumacker, R.A. A characterization of ten-hidden surface algorithms. Computing Surveys 6 (Mar. 1974), 1-56. Google ScholarDigital Library
- 7 Bui Tuong Phong and Crow, F.C. Improved rendition of polygonal models of curved surfaces. To be presented at the joint USA-Japan Computer Conference.Google Scholar
- 8 Warnock, J.E. A hidden-line algorithm for halftone picture representation. Dep. of Comput. Sci., U. of Utah, TR 4-15, 1969.Google Scholar
- 9 Watkins, G.S. A real-time visible surface algorithm. Dep. of Comput. Sci., U. of Utah, UTEC-CSc-70-101, June 1970.Google Scholar
- 10 Newell, M.E., Newell, R.G., and Sancha, T.L. A new approach to the shaded picture problem. Proc. ACM 1973 Nat. Conf.Google Scholar
- 11 Gouraud, H. Computer display of curved surfaces. Dep. of Comput. Sci., U. of Utah, UTEC-CSc-71-113, June 1971. Also in IEEE Trans. C-20 (June 1971), 623-629.Google Scholar
Index Terms
- Illumination for computer generated pictures
Recommendations
Models of light reflection for computer synthesized pictures
SIGGRAPH '77: Proceedings of the 4th annual conference on Computer graphics and interactive techniquesIn 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 ...
Models of light reflection for computer synthesized pictures
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 ...
An improved illumination model for shaded display
To accurately render a two-dimensional image of a three-dimensional scene, global illumination information that affects the intensity of each pixel of the image must be known at the time the intensity is calculated. In a simplified form, this ...
Comments