JOSM/Advanced Tricks

From OpenStreetMap

Or cool things about JOSM you didn't know existed.

1. Got multiple objects on top of each other and can't see them properly? The middle-click displays a dialog with all the object under the mouse. (On Apple/Mac OS X, this ability varies with the mouse type. This does not appear to be possible with a one-button mouse. With the Mighty Mouse, the scroll ball can be configured as "Button 3" to make this work.)
2. In addition to the prior trick, if you hold down the Control key (after you did the middle-click), it keeps the window, allowing you to select objects from the list. You may have to hold down the Alt key in addition to the Control key when selecting.
3. If you hold down the ALT key while deleting a way, JOSM will also delete the nodes in the way.
4. Use the command stack window to keep an eye on what's happening. It's very handy to noticing you've accidently moved a way you didn't intend.
5. You can look for mistyped tags by selecting everything (Ctrl-A) and then looking at the tag list. If you select a row and hit edit, the dropdown contains all the variations used. Don't actually hit OK here, that would change everything. Instead, use the Search tool to find the bad tags.
6. JOSM's search function is very extensive. You can match on key:foo and value:bar. There are the keywords "selected" for currently selected objects, "modified" for things changed in this session and "incomplete". You can invert conditions by prefixing a minus and use the pipe symbol as an OR. For details see JOSM/Search function.
7. See what streets haven't been labelled - search for 'highway' or 'name', and see what doesn't get highlighted
8. You've got an error message or a problem with a way/node and you only know an ID? Search for "id:<number>".
9. You have bulk of lake-data ? Use Bulk Importing instead.
10. Some window managers in linux (kde, enlightenment) catch the alt-mousebutton combination. This can be very disturbing if you want to create a new way that is attached to another one. This can be worked around by first clicking the mousebutton, then hitting alt, then releasing the mousebutton and then release alt. Sometimes you can also press another, unused, modifier togehter with alt to keep the window manager from grabbing it.
11. If the default node-movement delay settings get annoying, they can be overridden with the advanced settings edit.initial-move-delay (in milliseconds, defaults to 200) and edit.initial-move-threshold (in pixels, defaults to 15). Both these can be entered using the "Einstein Tab" of the JOSM preferences panel.
12. Got an .osm file from which you want to remove stuff? JOSM will normally not remove things but mark them with "action=delete" in the saved file. However, if you first change the file to use only negative IDs (sed -e 's/id="/id="-/' or similar), then JOSM will actually delete the items you delete, and write a reduced file when you save it.
13. Looking for the "invert selection" button? Use the "search" function and search for the expression "-selected".

More coming...