So I've been doing a lot of searching and haven't found exactly what I'm looking for. My math skills are a bit rusty, so I haven't had luck deriving this on my own.
What I'm looking for is an equation (or set of equations) where I can plug in starting and ending spherical coordinates, plus a percentage (ie [0,1]) and output spherical coordinates of some point in between (ie, progress along a great circle).
The idea is basically to chart the progress of a plane between two cities and draw it on a globe or map.
- r (radius)
- p (progress, from 0->1)
- lat_x,lon_x (point in-between)