Wrong Visualisation of the width of the carriageway when using the Lanes and Road Attributes mappaint style

[der_eine_lauch]

What steps will reproduce the problem?

1. When specifying a value for width:lane, the actual width of the lane is not displayed correctly in the Lanes and Road Attributes mappaint style.

What is the expected result?

That it shows the lanes exactly in the width they have. When I measure the visualized width of the lane with the ​measurement plugin, it should give the same width that I entered.

What happens instead?

For a three lane road, I added: width:lanes=3.8|3.8|3.8 (as documented ​here). When I measure the width with the ​measurement plugin, it says that each lane is 3.05 m wide although it is actually 3.8 m wide.

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

In ​this screenshot you can see that I added width:lanes=3.8|3.8|3.8 to ​this segment. When I measure the width of the first lane with the ​measurement plugin (thin green line), the result is that the width is 3.05m.

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2023-08-29 13:38:40 +0200 (Tue, 29 Aug 2023)
Revision:18822
Build-Date:2023-08-30 01:30:57
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (18822 de) Windows 10 64-Bit
OS Build number: Windows 10 Home 2009 (19045)
Memory Usage: 1095 MB / 2026 MB (581 MB allocated, but free)
Java version: 17.0.7+7-LTS, Azul Systems, Inc., OpenJDK 64-Bit Server VM
Look and Feel: com.sun.java.swing.plaf.windows.WindowsLookAndFeel
Screen: \Display0 1920×1080 (scaling 1.00×1.00) \Display1 1440×900 (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: de_DE
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 (2.2.0)
+ apache-commons (36034)
+ apache-http (35924)
+ continuosDownload (102)
+ ejml (35924)
+ geotools (36068)
+ jackson (36034)
+ jaxb (36118)
+ jna (36126)
+ jts (36004)
+ measurement (36126)
+ opendata (36126)
+ public_transport (36126)
+ tageditor (36126)
+ turnlanes-tagging (0.0.5)
+ undelete (36126)
+ utilsplugin2 (36134)

Map paint styles:
- https://josm.openstreetmap.de/josmfile?page=Styles/MapillaryDetections&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Styles/Enhanced_Lane_and_Road_Attributes&zip=1

Last errors/warnings:
- 00000.457 W: extended font config - overriding 'filename.Myanmar_Text=mmrtext.ttf' with 'MMRTEXT.TTF'
- 00000.460 W: extended font config - overriding 'filename.Mongolian_Baiti=monbaiti.ttf' with 'MONBAITI.TTF'
- 00004.137 W: Unable to request certificate of https://roottest-g3.pkioverheid.nl
- 00004.619 W: Unable to request certificate of https://roottest-g3.pkioverheid.nl
- 01340.903 W: java.net.SocketException: Socket closed. Ursache: java.net.SocketException: Socket closed
- 01340.905 E: java.net.SocketException: Socket closed. Ursache: java.net.SocketException: Socket closed

[der_eine_lauch]

Screenshot in JOSM

[taylor.smock]

Closed as duplicate of #8588.
From wiki:Styles/Lane_and_Road_Attributes, the style uses "[pixel] per metre (on average)". So it is on average correct. Unfortunately, the further you get away from where the average is "correct", the more of a difference there is between the average and the actual pixels per metre.

[der_eine_lauch]

Okay, thank you. But can this please be updated because it would be very useful if it is visualized in actual size.
Until this happens, it would be good to add this information to the documentation of this style, because I'm probably not the only one confused by this.

[taylor.smock]

Until this happens, it would be good to add this information to the documentation of this style

It is already in the documentation for the style (just not in the description, which is of limited length since otherwise people won't read it).