PhongShading
PhongShading[] is a three‐dimensional graphics directive that specifies that faces of polygons and other filled graphics objects are to be drawn to reflect as a smooth surface using a normal‐vector interpolation shading.
PhongShading[d] uses the attenuation factor d for the diffuse light.
PhongShading[d,s] uses the attenuation factor s for the specular light.
PhongShading[d,s,a] uses the attenuation factor a for the ambient light.
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