Sliders and marks

[Bastien Nocera <hadess hadess net>]

Heya,

Looking at bug https://bugzilla.gnome.org/show_bug.cgi?id=643487 and the
original https://bugzilla.gnome.org/show_bug.cgi?id=643486 we figured
that it would be best for sliders to point to their marks instead of
trying to add labels on the end of scales.

This is Jakub's mockup:
http://gitorious.org/gnome-design/gnome-design/blobs/master/mockups/theming/widget-dissect-slider.png
And my current implementation:
http://img64.imageshack.us/f/keyboardreversedscale.png/

The problem is that GtkScale allows for the marks to be placed above or
below scales, and that you can add one mark above, and one below.

I've already added a GTK_STYLE_CLASS_SCALE_HAS_MARKS class to gtk+,
should I add a GTK_STYLE_CLASS_SCALE_HAS_MARKS_BELOW and
GTK_STYLE_CLASS_SCALE_HAS_MARKS_ABOVE instead, and make the theming
engine do something special in the cases where all the marks are on one
particular side of the scale?

Do we want to handle vertical scales with marks as well? Are those used
at all?

Ideas welcome.