Utah teapot
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The Utah teapot is a 3D model which has become a standard reference object (and something of an in-joke) in the computer graphics community. It is a simple, round, solid, partially concave mathematical model of an ordinary teapot.
Utah_teapot.png
The teapot model was created in 1975 by early computer graphics researcher Martin Newell, a member of the pioneering graphics programme at the University of Utah. Newell needed a moderately simple mathematical model of a familiar object for his work, and his wife's teapot, a Melitta, provided a convenient solution. The shape contains a number of elements that make it ideal for the graphics experiments of the time — it is round, contains saddle points, has a genus greater than zero because of the hole in the handle, can project a shadow on itself, and looks reasonable when displayed without a complex surface texture.
Newell made the mathematical data that describes the teapot's geometry (largely a set of three-dimensional coordinates) publicly available, and soon other researchers began to use the same data for their computer graphics experiments. These researchers needed something with roughly the same characteristics that Newell had, and using the teapot data meant they didn't have to laboriously enter geometric data for some other object. Although technical progress meant that the simple act of rendering the teapot was no longer the challenge it was in 1975, the teapot continued to be used as a reference object for increasingly advanced graphics techniques. The common, rather squat appearance of the teapot differs from the Melitta original, reportedly because Newell's colleague Jim Blinn transformed it to compensate for the non-square pixels on his early frame buffer.
Over the following decades, editions of computer graphics journals (such as the ACM SIGGRAPH's quarterly) regularly featured versions of the teapot: faceted or smooth-shaded, wireframe, bumpy, translucent, refractive, even leopard-skin and furry teapots were created.
Versions of the teapot model, or sample scenes containing it, are distributed with or freely available for nearly every current rendering and modeling program, including AutoCAD, POV-Ray, OpenGL, Direct3D, and 3D Studio Max. Along with the expected cubes and spheres, the GLUT library even provides the function glutSolidTeapot() as a graphics primitive.
Teapot scenes are commonly used for renderer self-tests and benchmarks. In particular, the Teapot in a stadium benchmark and problem refer to the tough case of rendering of a scene with drastically changing density and scale of geometrical data representation in various parts of the scene.
With the advent first of computer generated short films, and then of full length feature films, it has become something of an in joke to hide a Utah teapot somewhere in one of the film's scenes. Utah teapots can be found in Toy Story, Monsters Inc., and Disney's Beauty and the Beast. The teapot also occasionally appears in the Pipes screensaver shipped with Microsoft Windows. It is also featured in one of the levels of the video game Super Monkey Ball 2.
The original version was never seen from below and has no surface to represent the base of the teapot. Later versions fixed this.
The original teapot now resides in the Computer History Museum (http://www.computerhistory.org/) in Mountain View, CA.
See also
External links
- Direct link to the image of Utah teapot at Computer History Museum (http://archive.computerhistory.org/resources/still-image/Teapot/src/102630883.jpg)
- A brief history of the Utah teapot (http://www.sjbaker.org/teapot/)
- Original data set (tgz) (http://sjbaker.org/teapot/teaset.tgz)
