High DPI on Windows 10

[gpermant@…]

What steps will reproduce the problem?

Opening JOSM on my new laptop, with Win 10 and 3840x2160 resolution

What is the expected result?

Legible text in all parts of JOSM

What happens instead?

Text is very small, hardly legible.
In Lists and trees, text overlaps.

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

URL:https://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2018-11-28 01:09:01 +0100 (Wed, 28 Nov 2018)
Build-Date:2018-11-28 00:26:41
Revision:14460
Relative:URL: ^/trunk

Identification: JOSM/1.5 (14460 de) Windows 10 64-Bit
OS Build number: Windows 10 Pro 1803 (17134)
Memory Usage: 628 MB / 1820 MB (202 MB allocated, but free)
Java version: 1.8.0_191-b12, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: \Display0 3840x2160
Maximum Screen Size: 3840x2160
Dataset consistency test: No problems found

Plugins:
+ imagery_offset_db (34641)
+ turnrestrictions (34643)

Last errors/warnings:
- W: Erweiterungen aktualisieren - org.openstreetmap.josm.plugins.PluginHandler$UpdatePluginsMessagePanel[,0,0,0x0,invalid,layout=java.awt.GridBagLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=9,maximumSize=,minimumSize=,preferredSize=]
- W: No configuration settings found.  Using hardcoded default values for all pools.

[gpermant]

Screenshot of overlapping, non-legible text in JOSM

[Don-vip]

High DPI on Windows requires Java >= 9. Please try with latest version of Java (11 right now)

[Don-vip]

See also #9995

[anonymous]

Replying to Don-vip:

High DPI on Windows requires Java >= 9. Please try with latest version of Java (11 right now)

Uugh!
I cannot switch to Java 9 all of a sudden.
All my own projects are based on Java 8.
I am convinced there are thousands out there in the same situation...

[GerdP]

You can use the newer JRE for JOSM only and the older for your projects.

[gpermant]

I managed to download and install an early access version of JRE 11 from softfamous.com. That, however, has expired on 16 Nov and I get all sorts of warnings. The JRE does not seem to be generally available yet.

Be that as it may: JOSM now is legible again and can be operated.
Thanks for the hint!
And I will see when there will be an up to date Version of JRE 11.

[Don-vip]

Replying to gpermant:

I managed to download and install an early access version of JRE 11 from softfamous.com. That, however, has expired on 16 Nov and I get all sorts of warnings. The JRE does not seem to be generally available yet.

Wow, be careful. This download looks like crap and could be potentially harmful (infected by virus).

Java is currently going through major changes and we won't advise to download it from Oracle soon. Right now the best way to get Java 11 is either from ​adoptopenjdk or ​Azul (Zulu).

[gpermant]

Wow, be careful. This download looks like crap and could be potentially harmful (infected by virus).

I had no problems with it, just the warnings...
anyway, I have since changed to the official Java JDK 11.0.1 from Oracle.
As I am developing in Java too, I will need it.

But now: how do I tell JOSM to use the JRE that came with the JDK 11?
It is now back on Java 8, with fonts illegibly small.

[GerdP]

Create a script that sets java_home and the path and start josm from that script.

[gpermant]

I just tried to set java_home via environment variables, to C:\Program Files\Java\jdk-11.0.1\bin
But that does not work [immediately], JOSM still has small fonts.

[GerdP]

Did you also set path?
Your script might look similar to this:

SETLOCAL
set java_home=%ProgramFiles%\Java\jre-11.0.1
set path=%java_home%\bin;%PATH%
start java.exe -Xmx2G -jar josm-latest.jar %1 %2 %3 %4 %5 %6 %7 %8 %9

[gpermant]

I tried with a script josmstart.bat filled with

SETLOCAL
set java_home=C:\Program Files\Java\jdk-11.0.1
set path=%java_home%\bin;%PATH%
start java.exe -Xmx2G -jar josm-latest.jar %1 %2 %3 %4 %5 %6 %7 %8 %9

But when starting it from the command line,
I just get a short flashing window, then it returns to the command line.

Isn't there an easier way to choose the necessary java version for JOSM?

[GerdP]

Well, this is a bit off topic.
1) make sure that the paths are correct, maybe add the full path to josm-latest.jar
2) for debugging remove the start and add pause as last line