Calculation Formula
(1) Appearance Altitude
M=(h-H-l*l/14.7)*k/l+k*k/14.7+H
M: Appearance
Altitude (m) of the Hindrance
H: Height
(m) of the View Point
h: Height
(m) of the Object
l: Distance
(km) to the Object
k: Distance
(km) to the Hindrance
(2) Hybeny's Distance Formula
D=sqrt((M*dP)*(M*dP)+(N*cos(P)*dR)*(N*cos(P)*dR))
D: Distance
between the two points (m)
P: Average
Latitude of the tow points
dP: Latitude
difference between the two points
dR: Longitude
difference between two points
M: Radius
of the meridian curvature
N: Radius of the prime vertical curvature
M=6334834/sqrt((1-0.006674*sin(P)*sin(P))^3)
N=6377397/sqrt(1-0.006674*sin(P)*sin(P))
(3) Grid Interpolation
Linear interpolation