Align nodes

[OSMDoudou]

With 'L' keyboard shortcut, nodes 1 and 3 determine the new position of node 2, which is not what I'd like.

What I'd like is nodes 1 and 2 determine the new position of node 3 (and possibly the other selected nodes).

Or a way to easily add node 3 in alignment of nodes 1 and 2.

For example, imagine you need to add a barrier in perfect alignment with an existing wall on a building.

You select an existing corner of the building, hit 'A' to add a node to form a new way representing the barrier.

Of course it's very hard to place that new node perfectly in alignment with the existing wall.

If you selected nodes 1, 2 and 3 and press 'L', you'll move node 2, which was presumably already correctly aligned and moving it is thus not desirable.

The "Angle Snapping" feature does it almost. [1]

"Almost" because it works with segments, so you can easily continue an existing barrier in perfect alignment.

But it doesn't work with selecting two nodes of a closed way. You would need to first split the segment from the building, draw the barrier and close the building way again, which is far from straightforward.

[1] https://josm.openstreetmap.de/wiki/Help/Action/Draw/AngleSnap