Draw a line from end point to start point of closest spline

Question

Using Geometry nodes (Blender 3.1), I am trying to figure out how to draw a line from the end point of one spline to the start point of the nearest spline in the same curve object. I hope this image clarifies.

I have sort of accomplished this by mapping a new line to all the points and then deleting points that already existed, leaving behind the new segments. But this method does it by index and leaves me with little to no control over which end point meets which start point.

My current method:

A common result of my current method:

I hope this makes sense, and that there is a possible solution. I have a hard time understanding the geometry proximity node, but I think the answer is in there somewhere.

Answer 1

This is a very specific question, and unfortunately there is only a specific answer here.

On the one hand you can't compare several segments within one object (e.g. with the node Geometry Proximity) without separating them somehow, and on the other hand there are just too many open questions in this case and you unfortunately didn't go into more detail.

But to solve this particular situation, you can go the way of selections:

Here I first separate the splines from each other. Since from your concrete example it can be read that in the order first the upper two segments were created, and then the lower segment was added, which therefore has the index $2$.

Next, I select the end and start points of the two upper curves.

At these points I instantiate further curves.

I then set the endpoints of these curves to the position of the nearest point from the separated geometry.

...I have no idea if this fits for your specific case, but it is in any case exactly the answer to your concrete question.