Given an ArcByCenterPoint, defined by:

- center position (lat,lon in WGS84)
- radius (meters)
- startAngle (degrees)
- endAngle (degrees)

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

Given an ArcByCenterPoint, defined by:

- center position (lat,lon in WGS84)
- radius (meters)
- startAngle (degrees)
- endAngle (degrees)

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

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
```

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