Precision Normals: Beyond Phong
نویسندگان
چکیده
Almost all graphics architectures today support Gouraud shading, linear color interpolation between vertices; system designers aim toward a Phong shading model, linear interpolants of surface normals with a lighting model that supports both diffuse and specular components, as a superior means of rendering accurate images. However, the Phong model still retains serious artifacts. In this paper, we point out the shortcomings of linear interpolation of normals, and present a surface interrogation method for parametrically defined surfaces. CR Categories: I.3.7 [Computer Graphics] Color, shading, shadowing, and texture; I.3.5 [Computer Graphics] Computational Geometry and Object Modeling Curve, Surface and Geometric Algorithms; I.3.3 [Computer Graphics] Picture/Image Generation Display algorithms. Additional
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