How to connect / 'join' lines selectively but automatically in QGIS

I had a similar problem a while back with How to join (draw new) lines that are close but not touching – large dataset

This is the same dataset, however I found a problem with what I did before. The line sections where joined with no discretion and some that were joined still don’t join when it comes to path finding algorithms.

The main dataset is a vector layer with lines (10k features). Some cross and intentionally ‘join’, others cross and intentionally don’t join and some don’t touch but should.

I have since been sent an additional layer with points of where lines should connect/intersect/join.

Part of my problem solving this has been the correct use of language as ‘Join’ and ‘Intersect’ is especially poor because it’s typically used for ‘joining’ attributes and intersecting features.

In addition to this I’m not familiar enough with path finding and if there’s a difference between line sections crossing and ‘actually’ intersecting… for my purposes I need to ensure that the lines intersect so a path finding algorithm will work (Network analysis -> ‘Shortest path’ seems to do the job)

Point where lines should join/connect/intersect – 1
Approx 25mm gap





Point where lines should join/connect/intersect – 2
Approx 0.03mm overshoot






Both issues seem to block path finding algor.

Is there a simple way to do this?

Methods I’m thinking about are:

Stopping short:

1. Snapping but somehow only for a subsect of the layer (e.g. union with the buffered points?)
2. Points to line/path (but I assume this draws lines between points which won’t solve my problem

Overshoot

1. I think this one should be simple with a split tool, but again I need help to figure out how to only do it in the proximity of a junction point.