Set VASSAL Look'n'Feel

[cholmcc]

Changing the Look’n’Feel of VASSAL

In Swing library (the Java Graphical User Interface - GUI) look’n’feel denotes the way the various GUI elements present. There are various look’n’feel (or lnf) available with a Java platform - some of them depending on who made the platform (yes, not all Java platforms are the same).

Name	Class
Metal	javax.swing.plaf.metal.MetalLookAndFeel
Nimbus	javax.swing.plaf.nimbus.NimbusLookAndFeel
CDE/Motif	com.sun.java.swing.plaf.motif.MotifLookAndFeel
GTK+	com.sun.java.swing.plaf.gtk.GTKLookAndFeel
Windows	com.sun.java.swing.plaf.windows.WindowsLookAndFeel
Windows Classic	com.sun.java.swing.plaf.windows.WindowsClassicLookAndFeel
Mac OS X	com.apple.laf.AquaLookAndFeel

The above table is in no way complete, and not all are available on all platforms.

Each Java platform defines a System look’n’feel which typically defaults to a reasonable value. For example, it will default to GTK on Linux and Solaris if installed with GTK support. On Windows, it will default to Windows or Windows Classic depending on the version of the OS (newer or older than Vista). On MacOS, it will be Mac OS X. If the defaults cannot be found, then every platform will fall back to Metal.

Note, look’n’feel is not the same as theme. For example, the GTK and Windows look’n’feels will use the corresponding GTK and Windows theme, respectively, set by the user. Also, some of the look’n’feels allow per-application theme-ing via Java byte-compiled code, most notably the Metal look’n’feel.

The regular way of setting the Java look’n’feel

In most Java applications, one can change the look’n’feel by several methods. The setting is given by one of the class names given in the above table.

• Setting the property swing.defaultlaf in $JAVA_HOME/conf/swing.properties, for example

  swing.defaultlaf=com.sun.java.swing.plaf.motif.MotifLookAndFeel
  

• Setting the property swing.defaultlaf on the command line:

  java -Dswing.defaultlaf=com.sun.java.swing.plaf.motif.MotifLookAndFeel ...
  

• In the application itself (see link above).

Demo

To see these look’n’feels in action download SwingSet2.jar and run it like

java -jar SwingSet2.jar 

Note:

• For Windows users, assume you have VASSAL installed in C:\Program Files\VASSAL, do

  C:\Program Files\VASSAL\jre\bin\java.exe -jar SwingSet2.jar 
  

• For MacOSX users, assume you have VASSAL installed in /Applications/VASSAL.app, do

  /Applications/VASSAL.app/Contents/MacOS/jre/bin/java -jar SwingSet2.jar
  

• For Linux users, just do the above command line.

Metal	Motif	Nimbus	GTK+	Mac OS X	Windows	Windows Classic

(Click on the images to enlarge)

Setting the look’n’feel for VASSAL

VASSAL sets the look’n’feel to the system look’n’feel explicitly on non-Windows platforms (e.g., Linux and MacOSX). That means we cannot use either swing.properties or the command -Dswing.defaultlaf to set the look’n’feel on those two platforms.

Below are some samples of a module running in VASSAL (click image to enlarge).

Metal	Motif	Nimbus	GTK+	Mac OS X	Windows	Windows Classic

On Windows

On Windows, VASSAL defaults to the Metal look’n’feel.

Since VASSAL ships with its own Java Virtual Machine (JVM), we should change the settings for that JVM. Suppose VASSAL is installed in C:\Program Files\VASSAL, then the Java Runtime Environment (JRE) is installed in

C:\Program Files\VASSAL\jre

and we have to edit

C:\Program Files\VASSAL\jre\conf\swing.properties

to have content like

swing.defaultlaf=com.sun.java.swing.plaf.windows.WindowsLookAndFeel

or any other look’n’feel available (typically, Metal, Nimbus, Motif, Windows, and WindowsClassic).

On MacOSX

Since VASSAL ships with its own Java Virtual Machine (JVM), we should change the settings for that JVM. However, since the VASSAL code explicitly sets the look’n’feel to be the system look’n’feel, we cannot simply specify a new swing.defaultlaf.

However, we can set the property swing.systemlaf to override the platform choice. But, we have to set it via the environment variable _JAVA_OPTIONS. Suppose VASSAL is installed in /Applications/VASSAL.app, then one can do for example

_JAVA_OPTIONS="-Dswing.systemlaf=javax.swing.plaf.metal.MetalLookAndFeel" \ 
    /Application/VASSAL.app/Contents/MacOS/VASSAL.sh

See also below for how to set this more permanently.

On Linux

Since the VASSAL code explicitly sets the look’n’feel to be the system look’n’feel, we cannot simply specify a new swing.defaultlaf. Instead, we must override the system look’n’feel via the environment variable _JAVA_OPTIONS. Assuming VASSAL is installed in /opt/vassal/current, then we could for example do

_JAVA_OPTIONS="-Dswing.systemlaf=javax.swing.plaf.metal.MetalLookAndFeel" \ 
    /opt/vassal/current/VASSAL.sh

See also below for how to set this more permanently.

Setting _JAVA_OPTIONS

There are several ways to set _JAVA_OPTIONS depending on your liking.

The first option is to set it in your shell configuration - e.g., ~/.profile, by adding a line like

export _JAVA_OPTIONS="-Dswing.systemlaf=javax.swing.plaf.metal.MetalLookAndFeel"

to that file. This will, however, set the look’n’feel for all Java applications.

Another option, is to create an alias in the same file (~/.profile) by adding a line like

alias vassal="_JAVA_OPTIONS=-Dswing.systemlaf=javax.swing.plaf.metal.MetalLookAndFeel /opt/vassal/current/VASSAL.sh"

again assuming /opt/vassal/current/VASSAL.sh is the appropriate path (for MacOSX it will be something like /Application/VASSAL.app/Contents/MacOS/VASSAL.sh).

Thirdly, you could generate a script in ~/.local/bin/vassal with content like

#!/bin/sh

_JAVA_OPTIONS=-Dswing.systemlaf=javax.swing.plaf.metal.MetalLookAndFeel \
    /opt/vassal/current/VASSAL.sh "$@"

again, with /opt/vassal/current/VASSAL.sh assumed to be the installation.

Note, if you used these instructions to integrate VASSAL into your Linux desktop, then the script ~/.local/bin/vassal has already been created and you can edit that. Note, to avoid overwriting your changes to that script, you can pass the option -W to the integration.sh script.

Custom Look’n’Feels

In principle, if one has a custom look’n’feel package - say mylaf.jar with class mine.MyLaF, one could do

_JAVA_OPTIONS="-classpath:/opt/vassal/current/lib/Vengine.jar:mylaf.jar -Dswing.systemlaf=mine.MyLaF" \
    /opt/vassal/current/VASSAL.sh 

to use the look’n’feel MyLaF. However, under the hood VASSAL does some funny and does not pass everything on to child processes. Thus, the above will only effect the Launcher - not the module windows.