Editing Isometric projection (section)

== History and limitations ==
{{main|Axonometric projection|Impossible object}}
{{multiple image
| width     = 150
| image1    = Optical-grinding engine model.jpg
| caption1  = Optical-grinding engine model (1822), drawn in 30° isometric.<ref>William Farish (1822) "On Isometrical Perspective". In: ''Cambridge Philosophical Transactions''. 1 (1822).</ref>
| image2    = Sanguo2.PNG
| caption2  = Example of axonometric art in an illustrated edition of the ''[[Romance of the Three Kingdoms]]'', China, c. 15th century.
}}
First formalized by Professor [[William Farish (professor)|William Farish]] (1759–1837), the concept of [[isometry]] had existed in a rough empirical form for centuries.<ref>Barclay G. Jones (1986). ''Protecting historic architecture and museum collections from natural disasters''. University of Michigan. {{ISBN|0-409-90035-4}}. p.243.</ref><ref>Charles Edmund Moorhouse (1974). ''Visual messages: graphic communication for senior students''.</ref> From the middle of the 19th century, isometry became an "invaluable tool for engineers, and soon thereafter axonometry and isometry were incorporated in the curriculum of architectural training courses in Europe and the U.S."<ref name="Kri96">J. Krikke (1996). "[http://www.iias.nl/iiasn/iiasn9/eastasia/krikke.html A Chinese perspective for cyberspace?] {{Webarchive| url=https://web.archive.org/web/20160205084728/http://www.iias.nl/iiasn/iiasn9/eastasia/krikke.html |date=2016-02-05 }}". In: ''International Institute for Asian Studies Newsletter'', 9, Summer 1996.</ref> According to Jan Krikke (2000)<ref name="Kri00">Jan Krikke (2000). "Axonometry: a matter of perspective". In: ''Computer Graphics and Applications, IEEE'' Jul/Aug 2000. Vol 20 (4), pp. 7–11.</ref> however, "axonometry originated in China. Its function in Chinese art was similar to [[linear perspective]] in European art. Axonometry, and the pictorial grammar that goes with it, has taken on a new significance with the advent of visual computing".<ref name="Kri00"/>

{{multiple image
| width     = 150
| image1    = IsometricFlaw 2.svg
| caption1  = An example of the limitations of isometric projection. The height difference between the red and blue balls cannot be determined locally.
| image2    = Impossible staircase.svg
| caption2  = The [[Penrose stairs]] depicts a staircase which seems to ascend (anticlockwise) or descend (clockwise) yet forms a continuous loop.
}}
As with all types of [[parallel projection]], objects drawn with isometric projection do not appear larger or smaller as they extend closer to or away from the viewer. While advantageous for [[architectural drawing]]s where measurements need to be taken directly, the result is a perceived distortion, as unlike [[perspective projection]], it is not how [[human vision]] or photography normally work. It also can easily result in situations where depth and altitude are difficult to gauge, as is shown in the illustration to the right or above. This can appear to create paradoxical or [[Impossible object|impossible shapes]], such as the [[Penrose stairs]].