How to draw a curve/path in 3D?

Hey Everyone.

I'm a layman user of Resolve/Fusion Studio, at no means doing this professionally.

I am trying a theoretically simple thing which turns out to not be as simple as I thought - I am animating a png geo-map in 3D space and want to animate a line/curve and a 3d object at the tip of the line to visualize the flight path (airplane from A to B)

What I managed so far - animate the map in an imageplane and animate the flight path as 2d polygon, put it on a second imageplane, rotate it 90°. For just the path alone, this perfectly does the trick.

But I cannot connect the animation of the 2d polygon line with the 3d object, syncing it with the progress of the line. I have to manually set individual keyframes on the transform3d of the object which doesn't come out as smooth and I have to manually adjust everything if the path changes.

On the other side, I can create a smooth animation of the 3d object alone but I don't find any ways to visualize the transform3d path to draw the flight path in 3d.

I see lots of tutorials on ribbons, benders, displacers and all kinds of ways to manipulate a line but honestly, nothing that really sounds useful to animate a simple curve between points A and B in 3d space that connects to a transform3d path.

Am I missing something?

It took some time to have my thread here approved, so in the meantime I did further research and stumbled across this tutorial

which led me to a decent solution.
So now I am using a particle emitter, reduced to smallest area size, with a long enough particle lifespan and a high subframe accuracy which I connect to my transform3d path and voilà I have something that resembles a line that follows a 3d path.
This feels like quite a workaround to create something as simple as a line but it works!

Still, happy about any feedback if I am missing a more straight-forward method here.

You're not missing something. This is currently not directly possible.
How 3D does your line itself need to be? Because if it's just a polyline with no 3D aspects to it, you can just do the line in 2D and the map in 3D. Use a locator connected to your 3D plane to drive the line in 2D space and you should be able to get decent results relatively easily.

Is this a workaround? Yes. And unfortunately there is no way around it, unless you manage to use the polygon shape tool combined with extrusion to get a curve into 3D space, but it will still be a 2D line in 3D space more or less.