Conformal projection of the Sphere within an equilateral triangle.
This is the North polar aspect, see the original Cox Projection (South polar aspect).
Original research by Philippe Rivière for d3-geo-projection, issue #118.
Read a write-up at visionscarto.net.
Reference papers:
J. F. Cox, Représentation de la surface entière de la terre dans un triangle équilatéral. Bulletin de la Classe des Sciences, Académie Royale de Belgique, 5, 21: 66-71. Bruxelles, 1935.
J. Magis, Calcul du canevas de la représentation conforme de la sphère entière dans un triangle équilatéral. Bulletin Geodésique, 247-256. Paris, 1938.
L.P. Lee, Conformal Projections Based On Dixon Elliptic Functions, Cartographica: The International Journal for Geographic Information and Geovisualization > Vol. 13, # 1, June 1976.
M. Douglas McIlroy, Wallpaper maps, 2011.
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