Flat shading
In contrast to Gouraud shading or Phong shading, flat shading or constant shading is a very simple shading method . With this method, each pixel of a polygon receives the same color or the same light value based on the surface normal. This results in a stepped, angular and unrealistic appearance of the objects, especially on curved surfaces (e.g. Mach stripes ).
In order to reduce the facet-like representation, the polygons would have to be reduced, which would result in an increased computational effort. Flat shading is therefore particularly useful for objects with flat surfaces ( cuboids , cubes , pyramids , prisms ...). For objects with curved surfaces ( cylinder , sphere , cone ...), however, Gouraud or Phong shading should be used.
According to the wireframe method , flat shading is the fastest algorithm for visualizing a 3D scene.