Make sure Hi-DPI is supported on every OS

[torakiki]

https://stackoverflow.com/questions/26182460/javafx-8-hidpi-support/26184471#26184471

[parrenin]

I was just about to buy a pdfsam license for my work computer, but I discovered this issue which is a stopper for me since I have a 4k screen. I hope the developers can do something about it soon.

[parrenin]

I forgot to say that I am on Debian 11 linux bullseye.

[torakiki]

For Basic you can just download it and try it to see if there's any issue with your monitor. For Visual pretty much the same, you can try it free for 14 days.

[parrenin]

I tried basic but everything is too small on the screen.

[21347]

Workaround for (probably most) Linux distributions: call pdfsam-basic with GDK_SCALE variable set to a reasonable amount, e.g.

GDK_SCALE=2 /opt/pdfsam-basic/bin/pdfsam-basic

Stolen from: https://superuser.com/questions/988379/how-do-i-run-java-apps-upscaled-on-a-high-dpi-display

You can also just edit the script at /opt/pdfsam-basic/bin/pdfsam-basic and insert the variable change just before the call to the java binary, e.g.

export GDK_SCALE=2
exec "$JAVACMD" -jar "$JAR_ARG" $JAVA_OPTS -Xmx512M \
  -Dapp.name="pdfsam-basic" \
  -Dapp.pid="$$" \
  -Dapp.home="$BASEDIR" \
  -Dbasedir="$BASEDIR" \
  -Dprism.lcdtext=false \
  org.pdfsam.basic.App \
  "$@"

Or tell the .desktop file (or just edit the menu entry) to add the variable to the command line, e.g. for Ubuntu/Min derivatives:

env GDK_SCALE=2 /opt/pdfsam-basic/bin/pdfsam-basic %F

The splash screen is still in dwarf-size mode, but the main Application is usable. I would assume that this is not a permanent fix, though, as setting the scale factor to a fixed value will not work for non HiDPI screens then.

[parrenin]

@21347: Thank you for the workaround, that will do it for my use case.

[torakiki]

We added an HowTo and a setting for the font size in version 5, this should cover pretty much all the needs