Re: Moving thumbnailing code

[Bastien Nocera <hadess hadess net>]

On Sun, 2016-06-26 at 13:45 +0200, Bastien Nocera wrote:
> Hey,
>
> gnome-desktop, the library, is a remnant of the old "libgnomeui" with
> useful widgets that could not be in GTK+, and helper utilities that
> might not be ready for merging in GLib.
>
> Nowadays, gnome-desktop only contains utilities that are shared
> between
> desktop components (gnome-settings-daemon, gnome-control-center,
> gnome-
> shell and gnome-initial-setup) and code to create thumbnails.
>
> The thumbnailing code has been something we've wanted to move to
> another part of the stack for a while, as a dependency on API/ABI
> unstable gnome-desktop really shouldn't be needed, but the problem is
> always "where".
>
> In https://bugzilla.gnome.org/show_bug.cgi?id=686895#c20
> Allison mentions D-Bus, or a giomodule.
>
> I've started shaving the yak slightly by moving images thumbnailing
> to
> an external process, the same used by every other thumbnailer:
>     https://bugzilla.gnome.org/show_bug.cgi?id=768043
>     https://bugzilla.gnome.org/show_bug.cgi?id=768062
>     https://bugzilla.gnome.org/show_bug.cgi?id=768064
>
> The code needs a bit more work, as I'd want to keep
> the G_FILE_ATTRIBUTE_PREVIEW_ICON usage within the thumbnailer.
> Should
> be done before anything else.
>
> Because I think that it would be nice for GLib/gio to contain both
> the
> code to generate and consume thumbnails, I'm leaning towards
> implementing the API in gio, returning GObjects *, with the pixbuf
> processing handled in a giomodule shipped in gdk-pixbuf.
>
> Another option would be to avoid all the giomodules, and either
> implement all the thumbnailing code in GTK+, or maybe the GdkPixbuf-
> handling parts in GIO, and non-graphical parts in GLib.
>
> Using a giomodule would allow us to eventually move away from gdk-
> pixbuf (if we are ever going to do this).
>
> Opinions?

Or we could just move it to gdk-pixbuf, which might be just high enough
in the stack to have gio and gdk-pixbuf support. Though that would mean
that thumbnailer and consumer would be in different places.