[Pan-devel] Partial Patch - Add the ability to scale images

[Darren Albers]

All,

Attached is a partial patch that gives the ability to scale images in 
the body pane.  I am posting it here in hopes that someone can point me 
in the right direction for the last piece, how do I determine the 
geometry of the body pane so I can scale the image appropriately?  The 
GTK toolkit has a number of function to determine window size but not 
the pane itself.  At this time I am just hard coding a value height and 
width to verify that everything works.  If all else fails I can make the 
scale size a user configurable option...

This patch adds a preference option to scale attached images and then 
uses the gdk_pixbuf_scale_simple() to scale the image down.  This patch 
should maintain the proper aspect ratio, I reused some code from eog to 
determine how to properly scale the image and it seems to handle all 
images properly but I thought a bit about it today and I think it is 
flawed for this use and I think I have a better way to handle it that I 
will look at tonight.

I am a poor programmer so I would appreciate any feedback, help, and hints!

Thanks!
Darren


diff -Nru /home/darren/pan-0.101/pan/gui/body-pane.cc 
/home/darren/pan-0.101.1/pan/gui/body-pane.cc
--- /home/darren/pan-0.101/pan/gui/body-pane.cc 2006-06-24 23:44:24.000000000 
-0400
+++ /home/darren/pan-0.101.1/pan/gui/body-pane.cc       2006-06-28 
21:37:54.000000000 -0400
@@ -505,7 +505,7 @@
    * Generates a GtkPixmap object from a given GMimePart that contains an 
image.
    * Used for displaying attached pictures inline.
    */
-  GdkPixbuf* get_pixbuf_from_gmime_part (const GMimePart * part)
+  GdkPixbuf* get_pixbuf_from_gmime_part (const GMimePart * part, const Prefs& 
prefs)
   {
     GdkPixbufLoader * l = gdk_pixbuf_loader_new ();
     GError * err (0);
@@ -525,6 +525,7 @@
   
     // create the pixbuf
     GdkPixbuf * pixbuf (0);
+    GdkPixbuf * scaled (0);
     if (!err)
       pixbuf = gdk_pixbuf_loader_get_pixbuf (l);
     else {
@@ -540,9 +541,29 @@
     }
     if (pixbuf)
       g_object_ref (G_OBJECT(pixbuf));
-    g_object_unref (G_OBJECT(l));
-
-    return pixbuf;
+      g_object_unref (G_OBJECT(l));    
+    if (prefs.get_flag ("scale-images-to-fit", true))
+    {
+    //Hard coding the pane height and width temporarily until I can figure out 
how to get the pane geometry.
+    int height = 600;
+    int width = 600;
+    int image_width = gdk_pixbuf_get_width (pixbuf);
+    int image_height = gdk_pixbuf_get_height (pixbuf);
+    //stolen from eog eog-image.c, this section determines how we scale the 
image
+       if (((gdouble) image_height/image_width) >
+           ((gdouble)width/height)) {
+               /* We scale to the top */
+               width = height * (gdouble)image_width/image_height;
+       } else {
+               /* We scale to the sides of the page */
+               height = width * (gdouble)image_height/image_width;
+       }
+        scaled = gdk_pixbuf_scale_simple (pixbuf, width, height 
,GDK_INTERP_BILINEAR);
+        return scaled;
+    }
+    else {
+       return pixbuf;
+    }
   }
 }
 
@@ -604,7 +625,7 @@
 
   // if it's a picture, draw it
   if (is_image) {
-    GdkPixbuf * pixbuf = get_pixbuf_from_gmime_part (part);
+    GdkPixbuf * pixbuf = get_pixbuf_from_gmime_part (part, _prefs);
     if (pixbuf != 0) {
       GtkTextIter iter;
       gtk_text_buffer_get_end_iter (_buffer, &iter);
@@ -1136,7 +1157,7 @@
 
   if ((key=="wrap-article-body") || (key=="mute-quoted-text") ||
       (key=="show-smilies-as-graphics") || (key=="show-all-headers") ||
-      (key=="show-text-markup"))
+      (key=="show-text-markup") || (key=="scale-images-to-fit"))
     refresh ();
 }
 
diff -Nru /home/darren/pan-0.101/pan/gui/prefs-ui.cc 
/home/darren/pan-0.101.1/pan/gui/prefs-ui.cc
--- /home/darren/pan-0.101/pan/gui/prefs-ui.cc  2006-05-28 13:54:00.000000000 
-0400
+++ /home/darren/pan-0.101.1/pan/gui/prefs-ui.cc        2006-06-28 
21:13:25.000000000 -0400
@@ -321,6 +321,11 @@
     HIG :: workarea_add_wide_control (t, &row, w);
 #if GTK_CHECK_VERSION(2,6,0)
   HIG::workarea_add_section_divider (t, &row);
+  HIG::workarea_add_section_title (t, &row, _("Image Options"));
+    HIG :: workarea_add_section_spacer (t, row, 1);
+    w = new_check_button (_("Scale Images to fit"), "scale-images-to-fit", 
false, prefs);
+    HIG :: workarea_add_wide_control (t, &row, w);
+  HIG::workarea_add_section_divider (t, &row);
   HIG::workarea_add_section_title (t, &row, _("Tasks"));
     HIG::workarea_add_section_spacer (t, row, 1);
     l = gtk_label_new_with_mnemonic (_("Save a_ttachments to path:"));