Abstract
In many industrial designs, such as automobiles and electrical products, evaluating the quality of curved surfaces in the design is very important. H the designer can confirm shapes of curved surfaces visually, working with photo-realistic computer generated images, the designer 2019;s “sense” is well utilized. In this paper we will demonstrate method for producing images which can be used by designers to evaluate the visual quality of free-form curved surfaces. The method uses the reflected images of cylindrical light sources. It is important that curved surfaces be displayed accurately, without polygonal approximation, and that the generated images be photo-realistic images, including shadows. The shading model presented in this paper satisfies these requirements.
Many offices, classrooms, and factories are lit with multiple fluorescent lamps arrayed in parallel rows on the ceiling. The shading technique presented in this paper is applicable to estimation of illuminance distribution in such an environment. Our method performs hidden surface removal and shadowing of curved surfaces without polygonal approximation, yielding accurate display.
Keywords
- Cylindrical light sources
- quality of curved surfaces
- shadows
- penumbra
- Bézier surfaces
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© 1992 Springer-Verlag Tokyo
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Nishita, T., Takita, S., Nakamae, E. (1992). A Shading Model of Parallel Cylindrical Light Sources. In: Kunii, T.L. (eds) Visual Computing. CG International Series. Springer, Tokyo. https://doi.org/10.1007/978-4-431-68204-2_27
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DOI: https://doi.org/10.1007/978-4-431-68204-2_27
Publisher Name: Springer, Tokyo
Print ISBN: 978-4-431-68206-6
Online ISBN: 978-4-431-68204-2
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