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


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • Lambertian reflectance — If a surface exhibits Lambertian reflectance, light falling on it is scattered such that the apparent brightness of the surface to an observer is the same regardless of the observer s angle of view. More technically, the surface luminance is… …   Wikipedia

  • Lambert's cosine law — See also: Lambertian reflectance In optics, Lambert s cosine law says that the radiant intensity observed from a Lambertian surface or a Lambertian radiator is directly proportional to the cosine of the angle θ between the observer s line of… …   Wikipedia

  • Geometric albedo — The geometric albedo of an astronomical body is the ratio of its actual brightness at zero phase angle (i.e. as seen from the light source) to that of an idealized flat, fully reflecting, diffusively scattering (Lambertian) disk with the same… …   Wikipedia

  • Bidirectional scattering distribution function — The definition of the BSDF (Bidirectional scattering distribution function) is not well standardized. The term was probably introduced in 1991 by Paul Heckbert ref|endnote veach1997 a. Most often it is used to name the general mathematical… …   Wikipedia

  • Integrating sphere — (i.e., white), having relatively small holes as needed for entrance and exit ports. The shape of the cavity is commonly spherical, hence the name. Its relevant property is a uniform scattering or diffusing effect. Light rays incident on any point …   Wikipedia

  • Oren–Nayar Reflectance Model — The Oren Nayar model, developed by Michael Oren and Shree K. Nayar, is a reflectance model for diffuse reflection from rough surfaces. It has been shown to accurately predict the appearance of a wide range of natural surfaces, such as concrete,… …   Wikipedia

  • Oren–Nayar reflectance model — The Oren Nayar reflectance model, developed by Michael Oren and Shree K. Nayar, is a reflectance model for diffuse reflection from rough surfaces. It has been shown to accurately predict the appearance of a wide range of natural surfaces, such as …   Wikipedia

  • Spectralon — reflectance material is a fluoropolymer resin that gives one of the highest diffuse reflectance of known materials or coatings over the UV VIS NIR region of the spectrum and exhibits highly Lambertian behavior. It can be machined into a wide… …   Wikipedia

  • Diffuse reflection — For reflection of charged particles, see Scattering from rough surfaces. Diffuse and specular reflection from a glossy surface[1] Diffuse reflection is the reflection of light from a surface such that an incident ray is reflected at many …   Wikipedia

  • Bidirectional reflectance distribution function — The bidirectional reflectance distribution function (BRDF; {f r(omega i , omega o) }) is a 4 dimensional function that defines how light is reflected at an opaque surface. The function takes an incoming light direction, omega i , and outgoing… …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”