Is there an equation to determine if an object at altitude A can be seen at altitude B if there is an object between them at altitude C?
Something to do with triangles I think... I know it has something to do with right angled triangles... Heres the problem I have a tower at point A and a technician at point B who needs to be in sight of the tower. I drew a diagram that showed to me that a peak between the two points could be seen over from closer up but would block the view from further away.
I know the distance between the technician and the tower and the distance between the peak and both other objects.
What you are seeking is the intersection of a segment $AB$ with a triangle $C$ in 3D:
Searching for that will lead to many discussions of the problem, by e.g., DanSunday.