How to compute coordinates of start/end points of a ArcByCenterPoint?

Question

Given an ArcByCenterPoint, defined by:

1. center position (lat,lon in WGS84)
2. radius (meters)
3. startAngle (degrees)
4. endAngle (degrees)

how can we compute the position (lat, lon) of start/end points? I'm looking for a formula.

Answer 1

You can find appropriate formulas in the section Destination point given distance and bearing from start point here
Excerpt:

Formula:
φ2 = asin( sin φ1 ⋅ cos δ + cos φ1 ⋅ sin δ ⋅ cos θ )     
λ2 = λ1 + atan2( sin θ ⋅ sin δ ⋅ cos φ1, cos δ − sin φ1 ⋅ sin φ2 )
where   
φ is latitude, λ is longitude, 
θ is the bearing (clockwise from north), 
δ is the angular distance d/R; 
d being the distance travelled, R the earth’s radius