Tracing (Follow) loops line back to first node after 4th node has been reached,

[anonymous]

What steps will reproduce the problem?

1. Reproduction is not at will but at a very high percentage. The scenario is having 2 side sharing polygons. Start tracing with the F key after setting the second node of a new line for the next polygon. Hold the F key and on the 4th node of the new line, the end connects back to the first node resulting in a closed ring ending any further tracing.

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

I've tried multiple ways of hard reproducing but can not, suspecting it has to do with the mouse pointer position relative to the first node and maybe zooming out whilst. Set the first and second node, then zoom out after the hitting the F key tracing to see where the new line is going.

Consciously not zooming out while tracing makes no difference. It's always after the 4th node, not before, not after. A trace started not at the corner join of the 2 side sharing polygons does not cause this to happen, only when started at the join node of 2 polygons. Maybe it's over eager snapping i.e. maybe suspending snap while tracing needs to be suspended.

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2023-03-01 15:17:42 +0100 (Wed, 01 Mar 2023)
Revision:18678
Build-Date:2023-03-02 02:30:57
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (18678 en_GB) Windows 10 64-Bit
OS Build number: Windows 10 Home 2009 (19045)
Memory Usage: 2090 MB / 4084 MB (1054 MB allocated, but free)
Java version: 17.0.5+8-LTS, Azul Systems, Inc., OpenJDK 64-Bit Server VM
Look and Feel: javax.swing.plaf.metal.MetalLookAndFeel
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
System property file.encoding: Cp1252
System property sun.jnu.encoding: Cp1252
Locale info: en_GB
Numbers with default locale: 1234567890 -> 1234567890
VM arguments: [-Dicedtea-web.bin.location=%UserProfile%\AppData\Local\Programs\OpenWebStart\javaws, -Djava.util.Arrays.useLegacyMergeSort=true, --add-exports=jdk.deploy/com.sun.deploy.config=ALL-UNNAMED, --add-opens=java.desktop/javax.swing.text.html=ALL-UNNAMED, --add-reads=java.naming=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.security.action=ALL-UNNAMED,java.desktop, --add-reads=java.base=ALL-UNNAMED,java.desktop, --add-exports=java.naming/com.sun.jndi.toolkit.url=ALL-UNNAMED,java.desktop, --add-opens=java.base/jdk.internal.loader=ALL-UNNAMED, --add-exports=java.desktop/com.apple.eawt=ALL-UNNAMED, --add-exports=java.desktop/sun.awt=ALL-UNNAMED,java.desktop, --add-opens=java.base/jdk.internal.ref=ALL-UNNAMED, --add-exports=java.base/sun.security.validator=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/com.sun.imageio.plugins.jpeg=ALL-UNNAMED, --add-exports=java.base/sun.net.www.protocol.jar=ALL-UNNAMED,java.desktop, --add-exports=java.base/jdk.internal.util.jar=ALL-UNNAMED,java.desktop, --add-opens=java.prefs/java.util.prefs=ALL-UNNAMED, --add-exports=java.base/com.sun.net.ssl.internal.ssl=ALL-UNNAMED,java.desktop, --add-exports=javafx.graphics/com.sun.javafx.application=ALL-UNNAMED, --add-modules=java.scripting,java.sql,javafx.controls,javafx.media,javafx.swing,javafx.web, --add-exports=java.desktop/sun.awt.X11=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/sun.applet=ALL-UNNAMED,java.desktop,jdk.jsobject, --add-exports=java.base/sun.net.www.protocol.http=ALL-UNNAMED,java.desktop, --add-opens=java.base/java.lang=ALL-UNNAMED, --add-exports=java.base/sun.security.util=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/com.sun.imageio.spi=ALL-UNNAMED, --add-reads=java.desktop=ALL-UNNAMED,java.naming, --add-opens=java.base/java.nio=ALL-UNNAMED, --add-exports=java.base/sun.security.x509=ALL-UNNAMED,java.desktop, --add-opens=java.desktop/javax.imageio.spi=ALL-UNNAMED, --add-exports=java.desktop/javax.jnlp=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.security.provider=ALL-UNNAMED,java.desktop]
Dataset consistency test: No problems found

Plugins:
+ Mapillary (2.1.1)
+ RoadSigns (36038)
+ apache-commons (36034)
+ buildings_tools (36011)
+ graphview (36011)
+ jaxb (35952)
+ jogl (1.2.3)
+ kendzi3d-resources (0.0.2)
+ log4j (36034)
+ notesolver (0.5.0)
+ pt_assistant (1ff2e15)
+ reltoolbox (35976)
+ reverter (36043)
+ routing (35978)
+ turnrestrictions (36011)
+ utilsplugin2 (36011)

Tagging presets:
+ https://raw.githubusercontent.com/yopaseopor/traffic_signs_preset_JOSM/master/IT.zip
+ https://github.com/kendzi/Simple3dBuildingsPreset/releases/download/0.9_2018-05-08/s3db-preset.zip

Map paint styles:
+ https://josm.openstreetmap.de/josmfile?page=Styles/PublicTransport&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Styles/ColorWays&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/IncompleteObjectWarnings&zip=1

Last errors/warnings:
- 03552.637 W: java.net.UnknownHostException: ecn.t3.tiles.virtualearth.net
- 03552.637 W: java.net.UnknownHostException: ecn.t2.tiles.virtualearth.net
- 03552.638 W: java.net.UnknownHostException: ecn.t1.tiles.virtualearth.net
- 03552.638 W: java.net.UnknownHostException: ecn.t2.tiles.virtualearth.net
- 03552.639 W: java.net.UnknownHostException: ecn.t0.tiles.virtualearth.net
- 03552.640 W: java.net.UnknownHostException: ecn.t3.tiles.virtualearth.net
- 03552.640 W: java.net.UnknownHostException: ecn.t0.tiles.virtualearth.net
- 03552.641 W: java.net.UnknownHostException: ecn.t3.tiles.virtualearth.net
- 10423.180 W: Unsaved changes - <html>The relation has been changed.<br><br>Do you want to save your changes?</html>
- 10548.413 W: Unsaved changes - <html>The relation has been changed.<br><br>Do you want to save your changes?</html>

[SekeRob]

The ticket was opened by me but can't edit this in. The site keeps forgetting my stored info and registering marks me as a spammer trying to get in (never ending Captcha loop).

[SekeRob]

As supplementary info, when this unwanted loopback has happened, then mousing the reverse button or hitting Ctrl+Z one time shows the Follow function had not actually been closed, shows the mouse is still linked to the trace line 4th node and tracing can be continued. Suspect though this is the expected behaviour same as with regular followed lines that have finished the loop.

Also, sequentially had this happen without any zooming in/out while hitting the F key, only moving the mouse away, but not moving mouse at all made no difference.

[skyper]

With a quick try using plain JOSM core and default settings, I cannot reproduce. Next time this happens, please, save the corresponding objects to a file and attach it, thanks.

Replying to SekeRob:

The ticket was opened by me but can't edit this in. The site keeps forgetting my stored info and registering marks me as a spammer trying to get in (never ending Captcha loop).

Sorry, only a few maintainers are allowed to change the reporter. I am not a member of this exclusive group.
Anyway, you need to log in on the website prior to reporting. Setting/Changing the user in the ticket creation does not work anymore for quite some time.
If you have problems with the Captcha, please, open a new ticket against the component Trac, thanks.

[SekeRob]

When the above happens, this happens too at validation "other duplicate nodes (1), 4 nodes node, node, node, node". The action is to copy a tree node with it's specs, say an olive tree, then copy V in the spots where the mouse is pointing at the next tree and the next, but no tree showing up, moving on to the next and the next. Eventually a tree shows up in the spot where the mouse happens to rests, anywhere, which in fact is then a stack of trees why the naked eye cant see as the are in the exact same pixel spot. (Unfortunately this GitHub instance does not seem to allow pasting screenshots directly else I'd show the validation screen).

When drawing a line, not following, sometimes the line is doing catch-up, sometimes 6-8-10 nodes of the line showing up in a rush, but at least in this operation the nodes of the line appear where the mouse was clicked on the image opposed to the trees seemingly not having remembered where the image was clicked... no buffering of the X/Y for each node.

The common denominator of the JOSM environ is that there is a large data set loaded, 250-300K, the present even 480K objects. When the session is saved to disk the size exceeds 80-85MB. Saving often by hand as I've had several times that the automatic backup is unrecoverable damaged on restart (we suffer power outages as common cause).

At any rate the follow/tracing issue at setting 4th node then the 5th jumping back to the first node no matter where the mouse is pointing, to create a closed way, is not a standalone issue. Notably, but for 1 case the follow has to start at the join of 2 previously mapped polygons. Except for the 1 case, starting a follow away from a join it does not happen. Again the commonality is having a larger data area loaded / dense data. The present one built from a near blank canvas but for roads between Montorio al Vomano and Castiglione Messer Raimondo.

Notable is that now with that data set loaded for about 3 hours the task manager shows the Zulu environment using 110MB ram of the 16GB available. I've seen the memory usage grow at times to 2-4GB, not sure what drives this... maybe the imagery tiles and the frequent flipping between the various to check if ESRI/Maxar shows the same as Bing and ESRI Clarity for a given piece of farmland, wood, orchard, road, building to see what is and what was.

apology for the verbosity, but these impair mapping quite a bit for me.

[skyper]

I really try to understand your problem but I am sorry I still do not get it. Note that follow line action does not stick to one certain way to follow and always stops if ways to different directions are an option to follow.

Most of your "verbosity" above is probably not related to your problem. Could you please come up with a step by step description with a small OSM data layer as example. Note, you can copy or merge selected objects to a new empty layer and attach any file, including pictures and OSM files, to the ticket. Thanks a lot.

[anonymous]

Actually, as things got worse, I've concluded this phenomena of the follow trace jumping the line end back to the start after the 4th node, always the 4th node when it happens, tracing on the same line, nothing there to make it stop or pause has everything to do with memory leaking, revealing possible race conditions as things slow down. Having started to use custom preferences, i'ts grown to 38, the higher the starting letter is in the alphabet, the longer it can take to the point the when opening the custom wood/forest pref, 38th in the sorted order, I can go for a coffee and come back.

Long story short, I pulled up a 180MB data file I worked in happily 3-4 months ago but for slowing tracing while the data file was growing. Now the memory use very rapidly went the 4.6GB, typing became excruciating slow and eventually JOSM said that I needed to close the session as else 'weird stuff could start happening", yes the word 'weird' was used'. This has been the 3rd or 4th time in the last week. Started annotating memory usage in intervals and the last session with a 55MB data file rapidly grew to 2.207GB. I unloaded the data file, removed all imagery layers to get to the JOSM introduction page and noted the aforemention 2.2.07GB use. Let it sit for over an hour and here we are, up still 2.267GB. Yes, I think there's a problem worth calling Houston over. This was most definitely not the case when starting JOSM use last year.

Anyway, you may close the ticket as this goes far and above the fix I was looking for, no command line suffix to expand the allowed memory will fix the present map an hour, save, exit JOSM, reload, map an hour, exit, reload and so on.

[GerdP]

Closed as duplicate of #23442.
Closed this as duplicate because the newer Ticket has the better description how to reproduce.