Honestly, it's not hard at all to fly to any given set of coordinates.
0, 90, 180, 270 is all you really need to know.
If you are at 100,-80 and need to get to -50, 20, you can do it "the hard way", and align yourself with 0, 90, 180 or 270 on the bearing indicator and fly in that direction and watch what your lat and log numbers do - either increase or decrease, until you reach your destination, or you can use something like:
https://edbearingcalc.neocities.org/ and it will tell you to align to a course of 146 degrees and fly that way until you reach your destination.
That's it. That's all there is to it.
Yeah, it might be nice to include this kind of functionality, but.. the math involved in calculating a heading is somewhat complex - here's an example:
"Bearing from point A to B, can be calculated as,β = atan2(X,Y),
where, X and Y are two quantities and can be calculated as:
X = cos θb * sin ∆L
Y = cos θa * sin θb – sin θa * cos θb * cos ∆L
Lets us take an example to calculate bearing between the two different points with the formula:
- Kansas City: 39.099912, -94.581213
- St Louis: 38.627089, -90.200203
So X and Y can be calculated as,
X = cos(38.627089) * sin(4.38101)
X = 0.05967668696
And
Y = cos(39.099912) * sin(38.627089) – sin(39.099912) * cos(38.627089) * cos(4.38101)
Y = 0.77604737571 * 0.62424902378 – 0.6306746155 * 0.78122541965 * 0.99707812506
Y = -0.00681261948
So as, β = atan2(X,Y) = atan2(0.05967668696, -0.00681261948)
β = 96.51°
This means, from Kansas City if we move in 96.51° bearing direction, we will reach St Louis." (source:
http://www.igismap.com/formula-to-f...-angle-between-two-points-latitude-longitude/)