Add a utility function to check whether the icontheme
will produce something better than missing-image for
a GIcon. Obviously, we can only answer this question
if the GIcon is a themed icon the begin with.
Add properties, and use string arrays instead of lists.
Among other things, this renames gtk_icon_theme_list_icons
to gtk_icon_theme_get_icon_names.
Fixes: https://gitlab.gnome.org/GNOME/gtk/issues/2410
If icon lookup fails or if loading it fails later, just always
fall back to the built in image-missing icon. Nobody is handling
missing icons in a sane way anyway.
If you *truly* need to handle missing icons, you need to manually
use gtk_icon_theme_has_icon().
While changing the loading code I also fixed an issue where it
was always passing "png" to pixbuf, now it also handles "xpm" if
that is the filename suffix.
We had a pretty complex setup where we tried to avoid scaling up themes from dirs
that specified a size. However, not only was it very complex, but it didn't quite
work with window scales, because when using e.g. a size 32 directory for 16@2x
the dir size is wrong anyway. Additionally it turns out most code either picks
an existing icon size, or uses the FORCE_SIZE flags, so it doesn't seem
like a useful behaviour.
This change drops the FORCE_SIZE flags, and always scales
icons. Additionally it moves the scaling of the icon to rendering,
which seems more modern, and allows us to (later) share icons loaded
for different sizes that happened to use the same source file (at
different scales).
Note that this changes the behaviour of
gtk_icon_paintable_download_texture() is it now returns the unscaled
source icon. However, ignore thats, as I plan to remove this function
and replace it with a way to render a paintable to a cairo-surface
instead.
Instead, rely on people passing fallbacks explicitly.
Alternatively, GThemedIcon provides the functionality to create
fallbacks, which is what GtkImage and the testsuite now use.
That method is slightly better, too, so the expected test results
have been updated accordingly.
There is no way to query contexts or do anything useful with them.
So don't keep track of them and don't make them an argument in public
APIs with the docs saying "I don't know what to use here, maybe read
some spec somewhere".
Those functions are unused and the documentation says "Returns some
random number that the icon theme creator chose" which does not seem at
all useful and an implementation detail.
So get rid of it.
We expose no API to get at any colors for drawing symbolics, so we
shouldn't have APIs to draw with them.
Apart from that, those APIs look like a box of crayons, not like an
icontheme.
Most users were just forgetting to set the proper flags.
And flags aren't the right way to set this anyway, it was just
acceptable as a workaround during GTK3 to not break API.
The API encouraged wrong usage - most of the users were indeed wrong.
Use the correct version instead:
gtk_icon_theme_get_for_display (gtk_widget_get_display ())
This function is not useful. Every icon theme
on my system either does not have that field,
or has it as 'folder'. So, just use 'folder'
when you need an example icon.
