Editing Utah teapot

{{short description|Computer graphics 3D reference and test model}}
{{use American English|date=January 2020}}
{{use mdy dates|date=January 2020}}
[[File:Utah teapot (solid).stl|thumb|right|A 3D [[STL (file format)|STL]] model of the teapot]]
[[File:Utah teapot simple 2.png|thumb|right|A 2008 rendering of the Utah teapot model]]
The '''Utah teapot''', or the '''Newell teapot''', is one of the [[List of common 3D test models|standard reference test models]] in [[3D modeling]] and an [[in-joke]]<ref>{{cite magazine|url=https://nautil.us/the-most-important-object-in-computer-graphics-history-is-this-teapot-235818/|title=The Most Important Object In Computer Graphics History Is This Teapot|magazine=[[Nautilus (science magazine)|Nautilus]]|last=Dunietz|first=Jesse|date=February 29, 2016|access-date=March 3, 2019}}</ref> within the [[computer graphics]] community. It is a [[mathematical model]] of an ordinary [[Melitta]]-brand [[teapot]] designed by {{ill|Lieselotte Kantner|de}} that appears solid with a nearly rotationally symmetrical body. Using a teapot model is considered the 3D equivalent of a [["Hello, World!" program]], a way to create an easy 3D scene with a somewhat complex model acting as the basic geometry for a scene with a light setup. Some [[Library (computing)|programming libraries]], such as the [[OpenGL Utility Toolkit]],<ref>{{cite web |website=www.opengl.org |author=Mark Kilgard |date=Feb 23, 1996 | url=http://www.opengl.org/resources/libraries/glut/spec3/node89.html | title=11.9 glutSolidTeapot, glutWireTeapot | access-date=October 7, 2011}}</ref> even have [[Subroutine|functions]] dedicated to drawing teapots.

The teapot model was created in 1975 by early computer graphics researcher [[Martin Newell (computer scientist)|Martin Newell]], a member of the pioneering graphics program at the [[University of Utah]].<ref>{{Cite book
 | last = Torrence | first = Ann
 | title = ACM SIGGRAPH 2006 Teapot on - SIGGRAPH '06
 | chapter = Martin Newell's original teapot: Copyright restrictions prevent ACM from providing the full text for this work
 | doi = 10.1145/1180098.1180128
 | id = Article No. 29
 | isbn = 978-1-59593-364-5
 | pages = 29
 | year = 2006
 | s2cid = 23272447
 }}</ref> It was one of the first to be [[3D modelling|modeled]] using [[Bézier curve]]s rather than precisely measured.

==History==
[[File:Original Utah Teapot.jpg|thumb|The actual [[Melitta]] teapot that [[Martin Newell (computer graphics)|Martin Newell]] modelled, displayed at the [[Computer History Museum]] in [[Mountain View, California]] (1990–present)]]
{{ external media
| float  = right
| width = 220px
| image1 = [http://www.computerhistory.org/revolution/computer-graphics-music-and-art/15/206/556 A scan of the original diagram Martin Newell drew up, to plan the Utah Teapot before inputing it digitally.]<br />Image courtesy of Computer History Museum.
}}
For his work, Newell needed a simple mathematical model of a familiar object. His wife, Sandra Newell, suggested modelling their [[tea set]] since they were sitting down for tea at the time. He sketched the teapot free-hand using graph paper and a pencil.<ref>{{cite web|title=The Utah Teapot - CHM Revolution|url=http://www.computerhistory.org/revolution/computer-graphics-music-and-art/15/206|website=Computer History Museum|access-date=20 March 2016}}</ref> Following that, he went back to the computer laboratory and edited [[bézier curve|bézier]] control points on a [[Tektronix]] [[storage tube]], again by hand. {{Citation needed|date=December 2008}}

The teapot shape contained a number of elements that made it ideal for the graphics experiments of the time: it was round, contained [[saddle point]]s, had a [[Genus (mathematics)|genus]] greater than zero because of the hole in the handle, could project a shadow on itself, and could be displayed accurately without a 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 [[Association for Computing Machinery|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.

Having no surface to represent its base, the original teapot model was not intended to be seen from below. Later versions of the [[data set]] fixed this.

The real teapot is 33% taller (ratio 4:3)<ref>{{Cite web|title=The Utah Teapot|url=http://www.holmes3d.net/graphics/teapot/?graphics/teapot|access-date=2021-07-10|website=www.holmes3d.net}}</ref> than 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 preferred the appearance of this new version and decided to save the file out of that preference.<ref>{{cite web|last1=Seymour|first1=Mike|title=Founders Series: Industry Legend Jim Blinn |url=http://www.fxguide.com/featured/founders-series-industry-legend-jim-blinn/|website=fxguide.com|access-date=15 April 2015|archive-url=https://web.archive.org/web/20120729175832/http://www.fxguide.com/featured/founders-series-industry-legend-jim-blinn|archive-date=2012-07-29|date=2012-07-25}}</ref>

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 [[API]]s, including [[AutoCAD]], [[Houdini (software)|Houdini]], [[Lightwave 3D]], [[Modo (software)|MODO]], [[POV-Ray]], [[3ds Max]], and the [[OpenGL]] and [[Direct3D]] helper libraries. Some [[RenderMan Interface Specification|RenderMan]]-compliant [[rendering (computer graphics)|renderers]] support the teapot as a built-in geometry by calling <code>RiGeometry("teapot", RI_NULL)</code>. Along with the expected cubes and spheres, the [[OpenGL Utility Toolkit|GLUT]] library even provides the function <code>glutSolidTeapot()</code> as a graphics primitive, as does its [[Direct3D]] counterpart [[D3DX]] (<code>D3DXCreateTeapot()</code>). While D3DX for Direct3D 11 does not provide this functionality anymore, it is supported in the DirectX Tool Kit.<ref name=DirectXTK>{{cite web |url=https://github.com/microsoft/DirectXTK/ |title=DirectX Tool Kit|date=November 29, 2022 | publisher=GitHub}}</ref> Mac OS X Tiger and Leopard also include the teapot as part of [[Quartz Composer]]; Leopard's teapot supports [[bump mapping]]. [[BeOS]] and [[Haiku (operating system)|Haiku]] include 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.<ref>{{cite journal |last1=Wald |first1=Ingo |first2=Carsten |last2=Benthin |first3=Philipp |last3=Slusallek |title=A Simple and Practical Method for Interactive Ray Tracing of Dynamic Scenes |journal=Technical Report, Computer Graphics Group |year=2002 |url=http://graphics.cg.uni-saarland.de/fileadmin/cguds/papers/2002/DynRT/DynamicRayTracing.pdf |publisher=Saarland University |archive-url=https://web.archive.org/web/20120323191204/http://graphics.cg.uni-saarland.de/fileadmin/cguds/papers/2002/DynRT/DynamicRayTracing.pdf |archive-date=2012-03-23}}</ref><ref>{{cite journal |last1=Klimaszewski |first1=K. |last2=Sederberg |first2=T.W. |title=Faster ray tracing using adaptive grids |journal=IEEE Computer Graphics and Applications |year=1997 |volume=17 |issue=1 |pages=42–51 |doi=10.1109/38.576857 |s2cid=29664150 |url=https://scholarsarchive.byu.edu/cgi/viewcontent.cgi?article=1669&context=facpub }}</ref>

===Original teapot model===
The original, physical Melitta teapot was purchased from [[Zions Co-operative Mercantile Institution|ZCMI]] (a department store in [[Salt Lake City]]) in 1974. It was donated to the [[The Computer Museum, Boston|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.<ref>{{cite book |title=Original Utah Teapot at the Computer History Museum |url=http://www.computerhistory.org/collections/accession/X398.84 |website=Computer History Museum |date=2001-09-28}}</ref> The original teapot the Utah teapot was based on was available from [[Porzellanfabrik Friesland]], once part of the German Melitta group.<ref name="Siems_2015"/><ref name=FrieslandPorzel>{{cite tweet |user=FrieslandPorzel |author=Friesland Porzellan |author-link=Friesland Porzellan |number=845221850900762625 |date=2017-03-24 |title=The original Utah Teapot was always produced by Friesland. We were part of the Melitta Group once, thats right. Got yours already?}}</ref> Originally it was given the rather plain name {{lang|de|Haushaltsteekanne}} ('household teapot');<ref name=RadioBremen>{{cite web|language=de|title=Eine Teekanne als Filmstar|url=https://www.radiobremen.de/bremenzwei/rubriken/reportagen/utah-teapot100.html|publisher=Radio Bremen|access-date=March 1, 2019|archive-date=April 1, 2019|archive-url=https://web.archive.org/web/20190401175656/https://www.radiobremen.de/bremenzwei/rubriken/reportagen/utah-teapot100.html|url-status=dead}}</ref> the company only found out about their product's reputation in 2017, whereupon they officially renamed it "Utah Teapot". It was available in three different sizes and various colors; the one Martin Newell had used is the white "1.4&nbsp;l Utah Teapot".<ref name=Teekanne>{{cite web |language=de |title=Teekanne 1,4l Weiß Utah Teapot |url=https://frieslandversand.de/teekanne-1-4l-weiss-utah-teapot?number=1209034011 |publisher=[[Friesland Versand GmbH]] |access-date=November 15, 2023|archive-url=https://web.archive.org/web/20230329105432/https://frieslandversand.de/teekanne-1-4l-weiss-utah-teapot|archive-date=March 29, 2023}}</ref>

The original teapot is no longer in production, following a fire at [[Friesland Porzellan]].<ref>{{cite news |title=Großbrand zerstört Porzellanfabrik in Varel |language=de |trans-title=Large fire destroys porcelain factory in Varel |author=Der Landesdienst Niedersachsen/Bremen (dpa/lni) |location=Varel, Germany |date=2023-06-30 |work=[[Deutsche Presse-Agentur]] |department=Brände [Fires] |via=[[Süddeutsche Zeitung]] |url=https://www.sueddeutsche.de/panorama/braende-varel-grossbrand-zerstoert-porzellanfabrik-in-varel-dpa.urn-newsml-dpa-com-20090101-230630-99-238140 |access-date=2023-12-25 |url-status=live |archive-url=https://web.archive.org/web/20231225194841/https://www.sueddeutsche.de/panorama/braende-varel-grossbrand-zerstoert-porzellanfabrik-in-varel-dpa.urn-newsml-dpa-com-20090101-230630-99-238140 |archive-date=2023-12-25}}</ref>

==Appearances==
[[File:The Six Platonic Solids.png|thumb|right|"The Six Platonic Solids", an image that humorously adds the Utah teapot to the five standard [[Platonic solid]]s]]
One famous [[Ray tracing (graphics)|ray-traced]] image, by James Arvo and David Kirk in 1987,<ref name="Arvo_1987">{{cite journal |first1= James |last1= Arvo |first2= David |last2= Kirk |journal= ACM SIGGRAPH Computer Graphics |title= Fast ray tracing by ray classification |year= 1987 |volume= 21 |issue= 4 |pages= 55–64 |doi= 10.1145/37402.37409 |doi-access= free }}</ref> shows six stone columns, five of which are surmounted by the [[Platonic solid]]s ([[tetrahedron]], [[cube]], [[octahedron]], [[dodecahedron]], [[icosahedron]]).  The sixth column supports a teapot.<ref>{{cite web|last1=Carlson|first1=Wayne|title=A Critical History of Computer Graphics and Animation |url=http://design.osu.edu/carlson/history/lesson20.html |publisher=OSU.edu |access-date=15 April 2015 |archive-url=https://web.archive.org/web/20120212183002/https://design.osu.edu/carlson/history/lesson20.html |archive-date=2012-02-12 |date=2007}}</ref> The image is titled "The Six Platonic Solids", with Arvo and Kirk calling the teapot "the newly discovered [[polyhedron|Teapotahedron]]".<ref name="Arvo_1987"/> This image appeared on the covers of several books and computer graphic journals.

The Utah teapot sometimes appears in the "Pipes" [[screensaver]] shipped with [[Microsoft Windows]],<ref>{{cite web |url=http://www.eeggs.com/items/493.html |title=Windows NT Easter Egg – Pipes Screensaver |website=The Easter Egg Archive |access-date=May 5, 2018}}</ref> but only in versions prior to Windows XP, and has been included in the "polyhedra" [[XScreenSaver]] hack since 2008.<ref>{{cite web|url=http://www.jwz.org/xscreensaver/changelog.html|title=changelog (Added the missing Utah Teapotahedron to polyhedra)|website=Xscreensaver|date=10 Aug 2008}}</ref>

[[Jim Blinn]] (in one of his "[[Project MATHEMATICS!]]" videos) proves an amusing (but [[Trivial (mathematics)|trivial]]) version of the [[Pythagorean theorem]]: construct a (2D) teapot on each side of a [[right triangle]] and the area of the teapot on the [[hypotenuse]] is equal to the sum of the areas of the teapots on the other two sides.<ref>{{cite AV media|title=Project Mathematica: Theorem Of Pythagoras|date=1988|url=https://archive.org/details/theorem_of_pythagoras|via=archive.org|publisher=NASA|access-date=28 July 2015|time=14:00}}</ref>

[[Vulkan (API)|Vulkan]] and [[OpenGL]] graphics APIs feature the Utah teapot along with the [[Stanford dragon]] and the [[Stanford bunny]] on their badges.<ref>{{cite web|author=Rob Williams|date=March 8, 2018|title=Khronos Group Announces Vulkan 1.1|publisher=Techgage Networks|url=https://techgage.com/news/khronos-group-announces-vulkan-1-1/|access-date=2020-01-18}}</ref>

With the advent of the first computer-generated short films, and later full-length feature films, it has become an [[in-joke]] to hide the Utah teapot in films' scenes.<ref>{{cite magazine|title=Tempest in a Teapot|magazine=Continuum|date=Winter 2006–2007|url=http://continuum.utah.edu/back_issues/2006winter/teapot.html|archive-url=https://web.archive.org/web/20140712192931/http://continuum.utah.edu/back_issues/2006winter/teapot.html|archive-date=2014-07-12|url-status=live}}</ref> For example, in the movie ''[[Toy Story]]'', the Utah teapot appears in a short tea-party scene. The teapot also appears in ''[[The Simpsons]]'' episode "[[Treehouse of Horror VI]]" in which Homer discovers the "third dimension."<ref>{{cite web|title=Pacific Data Images – ''Homer3''|url=http://cs.appstate.edu/~sjg/math/pacificdatahomer3d.html|url-status=live|archive-url=https://web.archive.org/web/20080724183923/http://www.cs.appstate.edu/~sjg/math/pacificdatahomer3d.html|archive-date=2008-07-24}}</ref> In ''[[The Sims 2]]'', a picture of the Utah teapot is one of the paintings available to buy in-game, titled "Handle and Spout".

An [[origami]] version of the teapot, folded by [[Tomohiro Tachi]], was shown at the [[Tikotin Museum of Japanese Art]] in Israel in a 2007–2008 exhibit.<ref>{{cite web|url=http://www.giladorigami.com/Tikotin/MA_Tachi.html|title=Tomohiro Tachi|work=Treasures of Origami Art|publisher=Tikotin Museum of Japanese Art|date=17 August 2007|access-date=2021-06-18}}</ref>
[[File:'Smithfield Utah' public sculpture.jpg|thumb|'Smithfield Utah' public sculpture in Dublin, Ireland]]
In Oct 2021 "Smithfield Utah" by Alan Butler which was inspired by the Utah teapot was unveiled in Dublin, Ireland.<ref>{{Cite web |title=Dublin City Council commission of public sculpture for Smithfield Square |url=https://www.sculpturedublin.ie/wp-content/uploads/2020/07/Sculpture-Dublin-Artist-Brief-Smithfield-Square.pdf |access-date=2023-04-23}}</ref><ref>{{Cite web |title=Central Area: Smithfield Square Lower – Sculpture Dublin |url=https://www.sculpturedublin.ie/smithfield-square/ |access-date=2023-04-23 |language=en-US}}</ref>

==OBJ conversion==
Although the original [[tea set]] by Newell can be downloaded directly, this tea set is specified using a set of Bézier patches in a custom format, which can be difficult to import directly into many popular 3D modeling applications. As such, a [[tesselated]] conversion of the dataset in the popular [[OBJ (file format)|OBJ file format]] can be useful. One such conversion of the complete Newell teaset is [https://www.cs.utah.edu/~natevm/newell_teaset/newell_teaset.zip available] on the University of Utah website.

==3D printing==
Through [[3D printing]], the Utah Teapot has come full circle from being a computer model based on an actual teapot to being an actual teapot based on the computer model. It is widely available in many renderings in different materials from small plastic knick-knacks to a fully functional ceramic teapot. It is sometimes intentionally rendered as a [[low poly]] object to celebrate its origin as a computer model.{{citation needed|date=November 2014}}

In 2009, a Belgian design studio, Unfold, 3D printed the Utah Teapot in ceramic with the objective of returning the iconographic teapot to its roots as a piece of functional dishware while showing its status as an icon of the digital world.<ref>{{cite news|title=Utanalog, Ceramic Utah Teapot |url=http://unfold.be/pages/utanalog |newspaper=Unfold Design Studio |date=October 28, 2009 |access-date=12 May 2015}}</ref>

In 2015, the California-based company Emerging Objects followed suit, but this time printed the teapot, along with teacups and teaspoons, out of actual tea.<ref>{{cite web|author1=[[Virginia San Fratello]]|author2=[[Ronald Rael]]|name-list-style=amp|date=2015|title=The Utah Tea Set|url=http://www.emergingobjects.com/projects/the-utah-tea-set|website=Emerging Objects|access-date=12 May 2015}}</ref>

==Gallery==
<gallery mode="packed">
Image:Calcomp 565 drum plotter.jpg|Wireframe Utah teapot on a 1960s-era Calcomp plotter
Image:utah teapot.png|The Utah teapot
Image:Environment mapping.png|[[Environment mapping]] on the teapot
</gallery>

==See also==

*[[List of common 3D test models]]
**[[3DBenchy]]
**[[Cornell box]]
**[[Stanford bunny]]
**[[Stanford dragon]]
**[[Suzanne (3D model)]]
*[[List of filmmaker's signatures]]
*[[Lenna]]
*[[Hyper Text Coffee Pot Control Protocol]]

==References==
{{Reflist|refs=
<ref name="Siems_2015">{{cite book |title=Melitta und Friesland Porzellan - 60 Jahre Keramikherstellung in Varel |language=de |trans-title=Melitta and Friesland Porzellan - 60 years manufacturing of ceramics in Varel |editor-first=Maren |editor-last=Siems |author-first1=Antje |author-last1=Sander |author-first2=Maren |author-last2=Siems |author-first3=Wilfried |author-last3=Wördemann |author-first4=Stefan |author-last4=Meyer |author-first5=Nina |author-last5=Janssen |publisher={{ill|Isensee Verlag|de}} |publication-place=Oldenburg, Germany |series={{ill|Schlossmuseum Jever|de|lt=Schloss Museum Jever}} |id=Begleitkatalog zur Ausstellung: Jeverland - in Ton gebrannt |edition=1 |volume=Jever Heft 33 |date=2015 |isbn=978-3-7308-1177-1 |pages=}} (48 pages)</ref>
}}

==External links==
{{commons category}}
* [http://www.computerhistory.org/collections/accession/102710359 Image of Utah teapot at the Computer History Museum]
* [http://www.computerhistory.org/revolution/computer-graphics-music-and-art/15/206 Newell's teapot sketch at the Computer History Museum]
* [http://www.sjbaker.org/wiki/index.php?title=The_History_of_The_Teapot S.J. Baker's History of the teapot] {{Webarchive|url=https://web.archive.org/web/20141120132346/http://www.sjbaker.org/wiki/index.php?title=The_History_of_The_Teapot |date=November 20, 2014 }}, including patch data
*[https://web.archive.org/web/20160821122527/http://design.osu.edu/carlson/history/lesson20.html Teapot history and images, from A Critical History of Computer Graphics and Animation] ([[Wayback Machine]] copy)
* [http://www.realtimerendering.com/udacity/?load=demo/unit1-teapot-demo.js WebGL teapot demonstration]
* [https://www.youtube.com/watch?t=6&v=DxMfblPzFNc History of the Teapot video from Udacity's online Interactive 3D Graphics course]
* [https://www.youtube.com/watch?v=TIxt9guMbXo The World's Most Famous Teapot] - [[Tom Scott (entertainer)|Tom Scott]] explains the story of Martin Newell's digital creation (YouTube)
{{Standard test item}}

{{DEFAULTSORT:Utah Teapot}}
[[Category:3D graphics models]]
[[Category:Test items]]
[[Category:Teapots]]
[[Category:In-jokes]]
[[Category:University of Utah]]