Craig retroazimuthal projection
Encyclopedia
The Craig retroazimuthal map projection
was created by James Ireland Craig in 1909. It is a cylindrical projection preserving the direction from any place to another, predetermined place while avoiding some of the bizarre distortion of the Hammer retroazimuthal projection. It is sometimes known as the Mecca projection because Craig, who'd worked in Egypt
as a cartographer, created it to help Muslims find their qibla
. The projection is defined by:
given latitude
, longitude relative to the fixed location 
, and latitude of the fixed location 
. For 
take 
, its continuous
completion.
Map projection
A map projection is any method of representing the surface of a sphere or other three-dimensional body on a plane. Map projections are necessary for creating maps. All map projections distort the surface in some fashion...
was created by James Ireland Craig in 1909. It is a cylindrical projection preserving the direction from any place to another, predetermined place while avoiding some of the bizarre distortion of the Hammer retroazimuthal projection. It is sometimes known as the Mecca projection because Craig, who'd worked in Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
as a cartographer, created it to help Muslims find their qibla
Qibla
The Qiblah , also transliterated as Qibla, Kiblah or Kibla, is the direction that should be faced when a Muslim prays during salah...
. The projection is defined by:
given latitude
, longitude relative to the fixed location , and latitude of the fixed location . For take , its continuousContinuous function
In mathematics, a continuous function is a function for which, intuitively, "small" changes in the input result in "small" changes in the output. Otherwise, a function is said to be "discontinuous". A continuous function with a continuous inverse function is called "bicontinuous".Continuity of...
completion.