finding the arc length on a sphere

Unity Engine
1

I have 2 points on a sphere and need to determine the length of the arc between them. Is there an easy way to do this?

I’ve looked at different sources on the net and found a few that address the problem. But I was hoping someone has already done this or that unity has a way to determine such things.

2

The trick is that an angle, in radians, IS the length of the arc along the unit circle/sphere. (That’s where the radian measurement comes from)

So get two Vector3’s representing the offset of each point from the sphere’s center. Use Vector3.Angle to get the angle between these vectors. This is in degree, so multiply it by Mathf.Deg2Rad to get it to radians. Now multiply that value by the radius of the sphere.

3

thanks I’ll try that