Feature idea: snap to ways in another layer

[cuu508]

Would it be feasible for this plugin (or a clone of this plugin) to have a feature where pressing a modifier key snaps the active node to the nearest way in another vector layer?

I understand a feature like this does may not fit well with the existing features, but perhaps this plugin can be a starting point for another plugin. I have no experience with developing JOSM plugins, and am wondering if this is feasible, and if perhaps anybody else would be interested in this as well.

Rationale:

I spend a fair bit of time improving accuracy of existing highways, usually aligning them to aerial imagery. But in my area there are also vector datasets from official sources with a compatible license I could make use of.

• I cannot just copy ways from other layers, as the ways in OSM already exist, they are just not always very accurate
• I know there is the conflation plugin, but the existing highways may consist of many segments, be partially used by route relations, so I'm not sure if the conflation plugin can be of much help here.
• The data quality from the official sources is of varying quality too. I would prefer to use the data manually and selectively, not import it wholesale.

The "Improve Way" tool is awesome, but cannot help but notice I spend hours just mechanically positioning mouse cursor, clicking, positioning mouse cursor a little further, clicking, and so on... Having a way to snap to a way in another layer would make the positioning step easier, and speed up my work significantly. I could use it on simple stretches of highways, and still deal with tricky areas (crossroads, places where reference data appears to have quality issues) manually.

Similar questions I've found:

• https://josm.openstreetmap.de/ticket/14259
• https://community.openstreetmap.org/t/snapping-in-josm/86034/3