April 17th, 2010
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So far every time I’ve used Qt applications under GNOME, especially VirtualBox, I’ve found the Qt font rendering to be appalling. See this screenshot of VirtualBox alongside the GNOME appearance dialog:
As you can see, most of my font settings are at the default “Sans” font. The “Sans” and “Sans serif” fonts , at least in recent Ubuntu releases, refer to the corresponding DejaVu font variants (previously it was Bitstream Vera). However as I found out through experimentation, whilst Qt is obeying my font settings, the generic “Sans” font seems to mean something completely different (at least to Qt4). If I instead specify the DejaVu fonts directly in my font settings, the correct font rendering is used:
So that’s it: if you’re using GNOME and you seem to get a Qt font rendering that doesn’t match your GTK font rendering, try using a more specific font. (Note: I haven’t got a clue what “Sans” actually means to GNOME, but it doesn’t appear to be a font in it’s own right.)