[Evolution-hackers] New (optional) dependency: GtkImageView

[Matthew Barnes <mbarnes redhat com>]

Before anyone freaks out the next time they try to build the master
branch, I wanted to mention that I've reworked the way we display image
attachments inline.

Basically I've handed the job over to Björn Lindqvist's GtkImageView
library [1], which handles pixbuf scaling, panning and caching better
than we do.  The new code takes the form of an EMFormat plugin called
"image-inline" (in the spirit of its siblings, "audio-inline" and
"vcard-inline").

To really see the plugin in action, find or send yourself a large image
attachment (wallpapers make for a good demo) -- something that Evolution
has to scale down to fit in its window.  Then double click the image and
use the mouse to pan around the full size image.  Double click again to
get back to the scaled down image.

The -real- benefit to us (er, mainly me I guess) is getting to rip out a
bunch of rusty old image handling code from the mailer, particularly in
em-format-html-display.c.

As always you can choose not to link to GtkImageView with a configure
option: --disable-image-inline.  But doing this will prevent you from
viewing "image/*" attachments directly in Evolution.

Matthew Barnes

[1]
http://trac.bjourne.webfactional.com/chrome/common/gtkimageview-docs/