Ideas for achieving clickable, KSP-like lines in the UI?

Here’s an example of what I mean:

I’m trying to think of how to get lines like this, which are;

  • Always the same screen size/thickness regardless of your distance and angle; ruling out vanilla splines or other in-world tricks (they will change size and thickness based on camera/perspective),
  • Hoverable/selectable; ruling out fancy particle effects.

My current plan is to calculate all of the curves myself, then sample them at fixed intervals, projecting those points into the UI and performing a bunch of 2D checks against the cursor’s location to figure out which is being hovered / selected. For rendering, I was thinking of somehow writing a HLSL shader that takes in those sampled points and constructs triangles and draws them, but not 100% sure on that yet. Might be a bit much.

Any ideas or pointers would be appreciated, particularly if they’re less ‘DIY’ than what I’m proposing.