The window "Domain" displays a domain (as a
wireframe) and a point (u0, v0) in the domain.
The window "Surface
X(u,v)" shows the sphere X(u,v) = (cos(u)cos(v), sin(u)cos(v), sin(v)),
the loxodrome X(Y(t)) where X(u,v) is the sphere as just defined and
Y(t) = (tan(beta)*(ln(t) – C), 2*arctan(t)), and the point X(Y(t0)).
The window "Projection" displays the projection of
the surface X(u,v) onto the tangent plane at X(u0, v0).
It is possible
to change C, beta, and t0 in the control window.