Lambertian surface

Lambertian surface

In the world of 3D computer graphics and visualisation, there exist many methods of representing how light sources interact with other objects in a virtual scene. These objects can be given certain properties such as: reflectivity, opacity, shading, smoothness, colour and texture. All of these (or particular combinations) can help increase the perceived reality of a virtual scene.

The term Lambertian surface refers to a technique used to light particular surfaces of virtual objects within a scene. This technique causes all closed polygons (e.g. a triangle within a 3D mesh) to reflect light equally in all directions when rendered. The effect this has from the viewer's perspective is that any rotation, scaling or translation of an object rendered in such a way does not result in a change of the shadows and highlights of the object's surface.

If we were to enlarge a cross section of a Lambertian surface, we would see a rough (or jagged) surface. So, there are no preferred angles of reflection. Lambertian surfaces are also called diffuse surfaces.

References

*Edward Angel, "Interactive Computer Graphics : A Top-Down Approach Using OpenGL", third edition (Addison Wesley, 2003), 277p

See also

*Lambert's cosine law
*Diffuse reflection


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