Icons and themes

[Bill Haneman <bill haneman sun com>]

Hi:

As some of you may know, certain kinds of themes would ideally like to
influence the way icons (and other similar widget pixmaps, like the
expanded/collapsed indicators in GtkTreeView) are rendered.

For accessibility, we need to provide the ability to use larger icons,
and to provide icons which have different visual characteristics
(high-contrast and low-contrast are the primary examples).  At a minimum
we need (to satisfy accessibility requirements) high-and-low-contrast
icons in both "standard" and "large" size.  (A single larger size should
suffice rather than a range of sizes, as users who need really big icons
probably would do better with an onscreen magnifier like the one that
the Gnopernicus project is building, or the sample magnifier utility in
at-spi).

At the moment our sample accessibility theme (high-contrast, large
print) is a gtkrc file-based theme which should work with the standard
theming engine (and other engines which honor gtkrc files).

What is the recommendation of gnome-libs and gtk+ developers as to how
we can best provide this?  It's not clear that an rc-file theme will do
the trick with the existing engines.

What we need is something that will work for GTK+ and also gnome stock
icons.

One possibility would be to write an engine which rescaled icons and
changed their contrast via filters - a fair bit of work, and probably
fairly ugly.  However it seems clear that such a thing is technically
possible using our existing API.

Are there better options that would not require massive API changes? 
And is there a simple mechanism that we could adopt for gtk stock icons
to specify an icon set?  Note that this could also be pressed into
service for the icon localization problem if the need arose.

Regards,

Bill