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Vertical Perspective Projection

\begin{figure}\begin{center}\BoxedEPSF{maps/vper.epsf scaled 500}\end{center}\end{figure}

A Map Projection given by the transformation equations

$\displaystyle x$ $\textstyle =$ $\displaystyle k'\cos\phi\sin(\lambda-\lambda_0)$ (1)
$\displaystyle y$ $\textstyle =$ $\displaystyle k'[\cos\phi_1\sin\phi-\sin\phi_1\cos\phi\cos(\lambda-\lambda_0)],$ (2)

where $P$ is the distance of the point of perspective in units of Sphere Radii and
$\displaystyle k'$ $\textstyle =$ $\displaystyle {P-1\over P-\cos c}$ (3)
$\displaystyle \cos c$ $\textstyle =$ $\displaystyle \sin\phi_1\sin\phi+\cos\phi_1\cos\phi\cos(\lambda-\lambda_0).$ (4)


Snyder, J. P. Map Projections--A Working Manual. U. S. Geological Survey Professional Paper 1395. Washington, DC: U. S. Government Printing Office, pp. 173-178, 1987.

© 1996-9 Eric W. Weisstein