3dRender.com : Glossary : 3D Rendering (for Dummies.)

3D Rendering - 3D Rendering is the process of producing an image based on three-dimensional data stored within a computer.

3D rendering is a creative process that is similar to photography or cinematography, because you are lighting and staging scenes and producing images. Unlike regular photography, however, the scenes being photographed are imaginary, and everything appearing in a 3D rendering needs to be created (or re-created) in the computer before it can be rendered. This is a lot of work, but allows for an almost infinite amount of creative control over what appears in the scene, and how it is depicted.

The three-dimensional data that is depicted could be a complete scene including geometric models of different three dimensional objects, buildings, landscapes, and animated characters - artists need to create this scene by Modeling and Animating before the Rendering can be done. The 3D rendering process depicts this three-dimensional scene as a picture, taken from a specified location and perspective. The rendering could add the simulation of realistic lighting, shadows, atmosphere, color, texture, and optical effects such as the refraction of light or motion-blur seen on moving objects - or the rendering might not be realistic at all, and could be designed to appear as a painting or abstract image.

NOTE: Even though they are called "3D," these images are not the same thing as the "3D Movies" that were popular in the 1950's, which created the illusion of depth on a movie screen when the audience wore special glasses. 3D computer graphics are called "3D," because of the way they are made, using 3D computer models to represent scenes before they are rendered. Although 3D graphics could be used in a 3D movie (if they ever became popular again), the final product of a 3D rendering is generally a regular two-dimension image, and these images can be used in printed pictures, on the internet, in interactive media, on TV, or in the movies.

Rendering sometimes takes a long time, even on very fast computers.  This is because the software is essentially "photographing" each pixel of the image, and the calculation of the color of just one pixel can involve a great deal of calculation, tracing rays of light as they would bounce around the 3D scene. To render all the frames of an entire animated movie (such as Shrek, Monsters Inc., or Ice Age) can involve hundreds of computers working continuously for months or years.

© 2002 by Jeremy Birn for 3dRender.com.