“Spherical shading” by Porter

  • ©Thomas (Tom) K. Porter




    Spherical shading



    Hidden surface algorithms in three-dimensional computer graphics have relied on polygons and patches as primitive objects. Spheres are shown to be computationally feasible for transforming and shading. A fast algorithm is presented for the shaded surface display of intersecting spheres. Problems of aliasing common to polygonbased images are resolved. The contribution to molecular graphics is demonstrated.


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