Editing Shading (section)

====Flat shading====
[[File:Shading1.jpg|thumb|Flat shading a [[Texture mapping|textured]] [[cuboid]]]]
[[File:Flat Shading applied to seashell graphics complex in Mathematica.svg|alt=graphics complex of a seashell with flat shading modeled in Mathematica|thumb|Graphics complex of a seashell with flat shading modeled in Mathematica]]
Here, the lighting is evaluated only once for each polygon (usually for the first vertex in the polygon, but sometimes for the [[centroid]] for triangle meshes), based on the polygon's surface normal and on the assumption that all polygons are flat. The computed color is used for the whole polygon, making the corners look sharp. This is usually used when more advanced shading techniques are too computationally expensive. [[Specular]] highlights are rendered poorly with flat shading: If there happens to be a large specular component at the representative vertex, that brightness is drawn uniformly over the entire face. If a specular highlight doesn't fall on the representative point, it is missed entirely. Consequently, the specular reflection component is usually not included in flat shading computation.