I am using OSGEarth version 2.10 DEVELOPMENT alongside OSG version 3.6.3.
In my application I'll use many high precision elevation maps, and would like to know whats the best/correct way to fetch the elevation at either mouse coordinates or at a specified location (Lat-Lon).
For testing, I have tried fetching coordinates on both an empty earth and one with a few srtm layers. My problem is that getting coordinates at an empty map yields either negative or near zero values, and the values are affected by zoom level. Am I maybe casting rays into the geometry?
When testing with srtm files, some areas in low elevation get very low (but still negative) values as well, which reinforces my previous guess. Mountainous regions are still showing high values, but maybe they could be off by a few meters, which would be an issue for my application.
So far, to get at mouse coordinates, I looked into the MouseCoordsTool and did something like: