翻訳と辞書
Words near each other
・ Utah State Route 99
・ Utah State Senate
・ Utah State Training School Amphitheater and Wall
・ Utah State University
・ Utah State University Eastern
・ Utah State University Honors Program
・ Utah State University Press
・ Utah State–Wyoming football rivalry
・ Utah statistical areas
・ Utah Stonewall Democrats
・ Utah Stories
・ Utah sucker
・ Utah Supreme Court
・ Utah Symphony
・ Utah System of Higher Education
Utah teapot
・ Utah Technology Council
・ Utah Telecommunication Open Infrastructure Agency
・ Utah Territorial Statehouse
・ Utah Territory
・ Utah Territory's at-large congressional district
・ Utah Test and Training Range
・ Utah Transfer of Public Lands Act
・ Utah Transit Authority
・ Utah Transit Authority Police Department
・ Utah Transportation Commission
・ Utah Utes
・ Utah Utes baseball
・ Utah Utes football
・ Utah Utes football under Bill Meek


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

Utah teapot : ウィキペディア英語版
Utah teapot

The Utah teapot or Newell teapot is a 3D computer model that has become a standard reference object (and something of an in-joke) in the computer graphics community. It is a mathematical model of an ordinary teapot of fairly simple shape, that appears solid, cylindrical and partially convex. A teapot primitive is considered the equivalent of a "hello, world" program, as a way to create an easy 3D scene with a somewhat complex model acting as a basic geometry reference for scene and light setup. Many programming libraries even have functions dedicated to drawing teapots.〔(【引用サイトリンク】 title=glutSolidTeapot )
The teapot model was created in 1975 by early computer graphics researcher Martin Newell, a member of the pioneering graphics program at the University of Utah.〔 (see ACM Digital Library reference ())〕
==History==
Newell needed a moderately simple mathematical model of a familiar object for his work. His wife Sandra Newell suggested modelling their tea service since they were sitting down for tea at the time. He got some graph paper and a pencil, and sketched the entire teapot by eye. Then he went back to the lab and edited bézier control points on a Tektronix storage tube, again by hand.
The teapot shape contains a number of elements that made 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 described the teapot's geometry (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 did not have to laboriously enter geometric data for some other object. Although technical progress has meant that the act of rendering the teapot is no longer the challenge it was in 1975, the teapot continued to be used as a reference object for increasingly advanced graphics techniques.
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.
The original teapot model was never intended to be seen from below, and had no surface to represent its base. Later versions of the data set fixed this.
The real teapot is noticeably taller (by a ratio of 4:3) compared to the computer model. Jim Blinn stated that he scaled the model on the vertical axis during a demo in the lab to demonstrate that they could manipulate it. They then liked the way this new version looked and saved the file.
The original, physical teapot was purchased from ZCMI (a department store in Salt Lake City) in 1974. It was donated to the Boston Computer Museum in 1984 where it was on display until 1990. It now resides in the ephemera collection at the Computer History Museum in Mountain View, California where it is catalogued as "Teapot used for Computer Graphics rendering" and bears the catalogue number X00398.1984.〔 (The date for the teapot itself was ca. 1974)〕
Versions of the teapot model, or sample scenes containing it, are distributed with or freely available for nearly every current rendering and modelling program and even many graphic APIs, including AutoCAD, Houdini, Lightwave 3D, MODO, POV-Ray, 3ds Max, and the OpenGL and Direct3D helper libraries. Some RenderMan-compliant renderers support the teapot as a built-in geometry by calling RiGeometry("teapot", RI_NULL). Along with the expected cubes and spheres, the GLUT library even provides the function glutSolidTeapot() as a graphics primitive, as does its Direct3D counterpart D3DX (D3DXCreateTeapot()). However version 11 of DirectX does not provide this functionality anymore. Mac OS X Tiger and Leopard also include the teapot as part of Quartz Composer; Leopard's teapot supports bump mapping. BeOS included a small demo of a rotating 3D teapot, intended to show off the platform's multimedia facilities.
Teapot scenes are commonly used for renderer self-tests and benchmarks.〔

抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)
ウィキペディアで「Utah teapot」の詳細全文を読む



スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース

Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.