I have an object that is 2000m above the earths surface. I can set the focal point to the object and easily rotate around the focal point, looking at the object from all sides. The moment I pan in any direction or zoom in/out using osgEarth built in panning functionality, the focal point is set to the projected position on the earths surface. After that, when I rotate I am rotating around a different focal point.
Is there a way to disable this kind of focal point resetting? If I zoom in/out I would like the focal point to stay the same. If I pan then I would like the focal point to move relatively to the transition.
I see there used to be an old API that tethered a point and was replaced by setViewpoint. I currently use setViewpoint so set the focal point but it does not tether the point.
You can tether to a GeoPoint by just setting the earth manipulator's viewpoint's focal point to your geopoint in mind. This can be going off in some sort of event handler to simulate tethering to that geopoint such that you can only zoom in and out from it and can't pan when locked in.