<Swing Dev> Fixing font sizes in GTKLookAndFeel

[Omair Majid]

Hi,

A while ago a user pointed out the issue that font sizes between GTK 
programs and Swing programs using the GTKLookAndFeel can be 
inconsistent. Digging through the code, here is a comment I found in
com.sun.java.swing.plaf.gtk.PangoFonts:

[snip]
     * Finally this DPI is used to calculate the nearest Java 2D font
     * 72 dpi font size.
     * There are cases in which JDK behaviour may not exactly mimic
     * GTK native app behaviour :
[snip]
     * 3) Because of rounding errors sizes may differ very slightly
     * between JDK and GTK. To fix that would at the very least require
     * Swing to specify floating pt font sizes.
     * Eg "10 pts" for GTK at 96 dpi to get the same size at Java 2D's
     * 72 dpi you'd need to specify exactly 13.33.
[snip]

As it turns out, Swing is fine with floating point font sizes: I can use 
affine transforms to scale the font. I also noticed that the Font class 
supports setting floating point font sizes (through a private 
constructor). I have created a patch that makes PangoFont avoid 
converting the size to integer units. The webrev is available at: 
http://cr.openjdk.java.net/~omajid/webrevs/gtk-floating-point-font-size-support/webrev.00/

Any comments and ideas are appreciated.

Thanks,
Omair