"Real time" Vs. "Rendered" (referring to graphics)

[avant-garde]

what does this mean?

[russ_watters]

"Real time" means something is done as you are watching it. "Rendered" is how a computer makes a picture. So "real time rendering" means a computer is generating the images as you are watching them, as opposed to what happens on a slower computer, where you have to wait.

IIRC, Toy Story is the first fully computer generated movie.... What do you get when you combine 28 animators, 117 dual and quad-processor SPARCstation 20 systems in a Renderfarm, 1,300 Renderman Shaders, 4.5 million lines of object code, and 34 terabytes of Renderman data files?

You end up with a 79 minute computer-generated animated movie...

With the success of Toy Story, the entertainment industry is now exploring areas of computer entertainment. The industry needs more than artists to make movies like this possible. Application developers are needed to create 3D programs, effects and shaders; as well as to develop the massively parallel renderfarm which took only 800,000 computer hours to generate the film's 114,240 frames. As a side note, if the producers began rendering Toy Story today on an average one-processor home computer, and the computer was used exclusively for the purpose of frame rendering, the animation would be complete in approximately 43 years. http://www.acm.uiuc.edu/banks/feb96/toystory.html

[IJovchevski]

it usually refers to processing aquired footage.
In editing, you have several stages.
The creative editing, making the story etc.. is usually done using real time as much as possible, even though it may show worse results.
When the project is finished, high quality rendering(not real time) is done.

[Nick89]

Think of video games. If you are actively playing the game (moving around in some environment for example), then the world is rendered (drawn) in real-time. It must be, because the game cannot predict what move you'll make. If you decide to look to your left, then the game suddenly has to draw what is to the left of you, and stop drawing what is to the right of you.

If, however, you encounter a cut-scene (as many games have), then you cannot actively control the game, but instead it plays a little 'movie' for you. Now, the game does know where 'you' will be looking next, so it doesn't have to render everything 'on the spot'. Instead, these cut-scenes are usually rendered during development. They are literally made into little movies that are simply played back to you.

This is the reason that cut-scenes often look much more realistic then in-game graphics: rendering a scene costs computing time. When the realism goes up, the computing time goes up too. Of course, while you are playing the game you don't want to wait 2 seconds before you can move 1 step forward, just because the game is busy rendering the world. So, less realistic graphics are used that can be rendered quickly.
For cut-scenes, the rendering is done beforehand, and it doesn't matter if it takes 2 second to generate a new frame. Once the scene has been rendered it can simply be replayed in the game at the correct speed.