That is, no dependence on the angle using cylindrical coordinates and no dependence on either angle using spherical coordinates.
From the en.wikipedia.org
The identity may be derived by considering the triangles formed by the tangent lines to the spherical triangle subtending angle C and using the plane law of cosines.
From the en.wikipedia.org
Once that is determined, the values are applied to a spherical triangle, and the angle from the local meridian to the required direction of Mecca can be determined.
From the en.wikipedia.org
Because of the cylindrical element in the lens, anamorphic lenses take in a horizontal angle of view twice as wide as a spherical lens of the same focal length.
From the en.wikipedia.org
That means even oily liquids can find their ideal angle with the surface and form a meniscus between adjacent toadstools that can support a spherical droplet.