It would be interesting to set a specific flyby altitude.

[aaron321]

Like on a path. Maybe this kind of thing already exists and I just don't know it yet.
For example, let's say I want to program my drone to fly past a statue perched on top of a buliding, but I need to know my drone won't crash into it.

Since the elevation from ground level is unpredictable, this would prove challenging.
Or maybe I should just buy an FPV drone and call it a day, lol.

 

[bumper]

A good rule of thumb, as you're approaching an object and the top of that object is below the distant horizon, you are above it.

 

[Skybuyer]

There is a relatively easy way to do that if you know in advance that you'll be flying in a particular area: Google Earth Pro.

One of the amazing features of Google Earth is that when you go to a location on the GEP map you can hover over anything and it will tell you the altitude MSL (above mean sea level). So what you need to do is find the launching point, note the altitude. Then hover over the obstacle and note that obstacle. The difference is the height from the launch area which will be 0, noted in feet about GROUND level (AGL). Not only will it help you know how high you have to be to clear a building or an obstacle, it will give you information about how high to set your RTH.

 

[izometric]

What I do to measure the height of a building (i.e. cross on top of a church):

I adjust the altitude relative to the building with the gimbal at zero. when the crosshair in the centre of the screen is targetting the highest point of the building, then that is my minimum height. From there I add 5 more meters for safety and I am very careful not to go below that during a flyover or an orbit.

 

[gslibey]