Editing Phong shading (section)

{{short description|Interpolation technique for surface shading}}
{{About|Phong's normal-vector interpolation technique for surface shading|Phong's illumination model|Phong reflection model}}
[[Image:Phong-shading-sample (cropped).jpg|upright=1.3|thumb|Flat shading (left) versus Phong shading (right)]]
{{3D computer graphics}}

In [[3D computer graphics]], '''Phong shading, Phong interpolation,<ref name="Watt1992">{{cite book |last=Watt |first=Alan H. |title=Advanced Animation and Rendering Techniques: Theory and Practice |author2=Watt, Mark |publisher=Addison-Wesley Professional |year=1992 |isbn=978-0-201-54412-1 |pages=21–26}}</ref>''' or '''normal-vector interpolation shading<ref name="Foley1996">{{cite book |last=Foley |first=James D. |title=Computer Graphics: Principles and Practice. (2nd ed. in C) |author2=van Dam, Andries |author3=Feiner, Steven K. |author4=Hughes, John F. |publisher=Addison-Wesley Publishing Company |year=1996 |isbn=0-201-84840-6 |pages=738–739}}</ref>''' is an [[interpolation]] technique for surface [[shading]] invented by computer graphics pioneer [[Bui Tuong Phong]]. Phong shading interpolates [[surface normal]]s across [[Raster graphics|rasterized]] polygons and computes [[pixel]] colors based on the interpolated normals and a reflection model. ''Phong shading'' may also refer to the specific combination of Phong interpolation and the [[Phong reflection model]].