Flag changed way segments going outside of the download area

[GerdP]

What steps will reproduce the problem?

1. Downlad an area that contains a small part of a landuse=residential" area which is crossed by a building
2. Move a node of the residential area so that the building is inside the area
3. Upload

What is the expected result?

A warning if the moved node changes a segment which ends outside of the download area, as this might produce more overlapping buildings in the area that was not downloaded.

What happens instead?

No such warning

Please provide any additional information below. Attach a screenshot if possible.

This is just an example because it happened to me recently. The same problem can happen when a
highway segment is moved.
I know this is difficult because we don't store the change of geometries so far. No idea if the validator is the right place to warn about this. Maybe it would be better to warn directly after the node move was done.

Revision:17458
Is-Local-Build:true
Build-Date:2021-01-13 16:03:15

Identification: JOSM/1.5 (17458 SVN en) Windows 10 64-Bit
OS Build number: Windows 10 Home 2004 (19041)
Memory Usage: 229 MB / 1972 MB (45 MB allocated, but free)
Java version: 15.0.1+9, AdoptOpenJDK, OpenJDK 64-Bit Server VM
Look and Feel: com.sun.java.swing.plaf.windows.WindowsLookAndFeel
Screen: \Display0 1920×1080 (scaling 1,00×1,00)
Maximum Screen Size: 1920×1080
Best cursor sizes: 16×16→32×32, 32×32→32×32
Dataset consistency test: No problems found

Plugins:
+ ColumbusCSV (35640)
+ OpeningHoursEditor (35640)
+ apache-commons (35524)
+ buildings_tools (35669)
+ ejml (35458)
+ geotools (35458)
+ jaxb (35543)
+ jts (35458)
+ o5m (35640)
+ opendata (35640)
+ pbf (35650)
+ poly (35640)
+ reverter (35640)
+ undelete (35640)
+ utilsplugin2 (35682)

Validator rules:
+ c:\josm\core\resources\data\validator\combinations.mapcss
+ c:\josm\core\resources\data\validator\geometry.mapcss

Last errors/warnings:
- 00000,528 W: extended font config - overriding 'filename.Myanmar_Text=mmrtext.ttf' with 'MMRTEXT.TTF'
- 00000,531 W: extended font config - overriding 'filename.Mongolian_Baiti=monbaiti.ttf' with 'MONBAITI.TTF'

[GerdP]

Another idea would be to add a node at the place where the - not yet moved - way segment crosses the download area.

[skyper]

I`d go with a warning right after the action but please in both direction, e.g. moving from outside to inside and moving from inside to outside.

[GerdP]

The ticket is not about moving a node outside of the download area. It is about moving a node of a way where the next node is outside.

[skyper]

Replying to GerdP:

The ticket is not about moving a node outside of the download area. It is about moving a node of a way where the next node is outside.

Thanks. Still would prefer a warning with the action and not later from validator.

There are quite some actions which can lead to moving one or some nodes. How should e.g. deleting the last inside node be handled.

[GerdP]

There is another situation which could be flagged. Sometimes I try to improve a way by selecting the virtual node in the middle of a segment and JOSM "fails to recognize my goal" and selects the whole way instead. Thus instead of adding a new node I move a way. We have preference warn.move.maxelements but this often complains at the wrong place, so I don't want to lower its value. I wonder if it would be better to have a warning whenever I change the positiion of an old way segment which is not completely visible.