Gnomonic projection: Difference between revisions

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==Equations==
==Equations==
===Gnomonic Projection===
===Gnomonic Projection===
Copied from Mathworld<br>
Copied from [https://mathworld.wolfram.com/GnomonicProjection.html Mathworld]
Inputs: <br>
 
<math>(\lambda, \phi)</math> Current spherical coordinate<br>
Inputs:
<math>(\lambda_0, \phi_1)</math> Spherical coordinate of tangent plane.<br>
* <math>(\lambda, \phi)</math> Current spherical coordinate with longitude <math>\lambda</math> and latitude <math>\phi</math>
* <math>(\lambda_0, \phi_1)</math> Spherical coordinate of tangent plane.
 
Outputs: <br>
Outputs: <br>
Cartesian coordinates.
* <math>(x,y) \in (-\infty, \infty) \times (-\infty, \infty)</math> Cartesian coordinates.
<math>(x,y) \in (-\infty, \infty) \times (-\infty, \infty)</math><br>
 
<br>
<math>x = \frac{\cos(\phi)\sin(\lambda - \lambda_0)}{\cos(c)}</math><br>
<math>x = \frac{\cos(\theta)\sin(\lambda - \lambda_0)}{\cos(c)}</math><br>
<math>y = \frac{\cos(\phi_1)\sin(\phi)-\sin(\phi_1)\cos(\phi)\cos(\lambda - \lambda_0)}{\cos(c)}</math><br>
<math>y = \frac{\cos(\phi_1)\sin(\phi)-\sin(\phi_1)\cos(\phi)\cos(\lambda - \lambda_0)}{\cos(c)}</math><br>
where <math>c</math> is the angular distance of the point <math>(x,y)</math> from the center of the projection, given by<br>
where <math>c</math> is the angular distance of the point <math>(x,y)</math> from the center of the projection, given by<br>