Field of view Area Calculations

Hello! Thanks again for helping us, excited to see version 11! Congrats!!

I am thinking of ways to calculate an ‘area’ that falls within a field of view. For instance, I have a three geodesic points, together they create a ‘triangle’. I want to see what % of the triangle falls within a field of view. My foremost thought is to use a ‘point map’ of Topocentric frames, filling the area of interest with points and toggle a boolean as they trigger the field of view event detector.

My question, have we thought about this type of problem? Is there a better way to go about this than a point map?

if no, then if there a good way to calculate the ‘great circle’ (shortest path) between 2 geodesic points/Topocentric frames that has been implemented in orekit already? I am using linear interpolation right now, but its a bit janky, especially at the poles.

Sincerely, Thank you;
Go Space!


For simple shapes like this, there may be a better way, but we have to think more about it. It certainly isn’t implemented yet. The problem is that we talk about two shapes (field of view and ground area) that have not the same center, so we don’t use geometry mapped on a 2-sphere topology, we use Cartesian 3D geometry.

Yes, and it works for any number of points. Is is implemented in Hipparchus. Look for the WelzlEncloser class in org.hipparchus.geometry.enclosing. It is already used in Orekit as an initial filter to speed up computation for small zones with complex shape: we first check if a point lies inside the smallest enclosing circle before attempting the full computation with the accurate shape definition.

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