[nautilus] file: keep scaled thumbnail in cache

[Cosimo Cecchi <cosimoc src gnome org>]

commit cbee96ac593dd35f4e10d88085e4feec2c569a9b
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Sat Aug 30 19:26:38 2014 -0700

    file: keep scaled thumbnail in cache
    
    Or we'll constantly re-scale it every time a client asks for the icon.

 libnautilus-private/nautilus-directory-async.c |    5 +++
 libnautilus-private/nautilus-file-private.h    |    5 ++-
 libnautilus-private/nautilus-file.c            |   39 +++++++++++++++--------
 3 files changed, 34 insertions(+), 15 deletions(-)
---
diff --git a/libnautilus-private/nautilus-directory-async.c b/libnautilus-private/nautilus-directory-async.c
index 251081f..afc41b2 100644
--- a/libnautilus-private/nautilus-directory-async.c
+++ b/libnautilus-private/nautilus-directory-async.c
@@ -3467,6 +3467,11 @@ thumbnail_done (NautilusDirectory *directory,
                g_object_unref (file->details->thumbnail);
                file->details->thumbnail = NULL;
        }
+       if (file->details->scaled_thumbnail) {
+               g_object_unref (file->details->scaled_thumbnail);
+               file->details->scaled_thumbnail = NULL;
+       }
+
        if (pixbuf) {
                if (tried_original) {
                        thumb_mtime = file->details->mtime;
diff --git a/libnautilus-private/nautilus-file-private.h b/libnautilus-private/nautilus-file-private.h
index 28a4601..5dd41ba 100644
--- a/libnautilus-private/nautilus-file-private.h
+++ b/libnautilus-private/nautilus-file-private.h
@@ -91,7 +91,10 @@ struct NautilusFileDetails
        char *thumbnail_path;
        GdkPixbuf *thumbnail;
        time_t thumbnail_mtime;
-       
+
+       GdkPixbuf *scaled_thumbnail;
+       double thumbnail_scale;
+
        GList *mime_list; /* If this is a directory, the list of MIME types in it. */
 
        /* Info you might get from a link (.desktop, .directory or nautilus link) */
diff --git a/libnautilus-private/nautilus-file.c b/libnautilus-private/nautilus-file.c
index 80137be..466023e 100644
--- a/libnautilus-private/nautilus-file.c
+++ b/libnautilus-private/nautilus-file.c
@@ -804,6 +804,10 @@ finalize (GObject *object)
        if (file->details->thumbnail) {
                g_object_unref (file->details->thumbnail);
        }
+       if (file->details->scaled_thumbnail) {
+               g_object_unref (file->details->scaled_thumbnail);
+       }
+
        if (file->details->mount) {
                g_signal_handlers_disconnect_by_func (file->details->mount, file_mount_unmounted, file);
                g_object_unref (file->details->mount);
@@ -4297,17 +4301,26 @@ nautilus_file_get_icon (NautilusFile *file,
                                thumb_scale = (double) NAUTILUS_ICON_SIZE_SMALLEST / s;
                        }
 
-                       scaled_pixbuf = gdk_pixbuf_scale_simple (raw_pixbuf,
-                                                                MAX (w * thumb_scale, 1),
-                                                                MAX (h * thumb_scale, 1),
-                                                                GDK_INTERP_BILINEAR);
-
-                       /* We don't want frames around small icons */
-                       if (!gdk_pixbuf_get_has_alpha (raw_pixbuf) || s >= 128 * scale) {
-                               if (nautilus_is_video_file (file))
-                                       nautilus_ui_frame_video (&scaled_pixbuf);
-                               else
-                                       nautilus_ui_frame_image (&scaled_pixbuf);
+                       if (file->details->thumbnail_scale == thumb_scale &&
+                           file->details->scaled_thumbnail != NULL) {
+                               scaled_pixbuf = file->details->scaled_thumbnail;
+                       } else {
+                               scaled_pixbuf = gdk_pixbuf_scale_simple (raw_pixbuf,
+                                                                        MAX (w * thumb_scale, 1),
+                                                                        MAX (h * thumb_scale, 1),
+                                                                        GDK_INTERP_BILINEAR);
+
+                               /* We don't want frames around small icons */
+                               if (!gdk_pixbuf_get_has_alpha (raw_pixbuf) || s >= 128 * scale) {
+                                       if (nautilus_is_video_file (file))
+                                               nautilus_ui_frame_video (&scaled_pixbuf);
+                                       else
+                                               nautilus_ui_frame_image (&scaled_pixbuf);
+                               }
+
+                               g_clear_object (&file->details->scaled_thumbnail);
+                               file->details->scaled_thumbnail = scaled_pixbuf;
+                               file->details->thumbnail_scale = thumb_scale;
                        }
 
                        g_object_unref (raw_pixbuf);
@@ -4327,9 +4340,7 @@ nautilus_file_get_icon (NautilusFile *file,
                        DEBUG ("Returning thumbnailed image, at size %d %d",
                               (int) (w * thumb_scale), (int) (h * thumb_scale));
                        
-                       icon = nautilus_icon_info_new_for_pixbuf (scaled_pixbuf, scale);
-                       g_object_unref (scaled_pixbuf);
-                       return icon;
+                       return nautilus_icon_info_new_for_pixbuf (scaled_pixbuf, scale);
                } else if (file->details->thumbnail_path == NULL &&
                           file->details->can_read &&                           
                           !file->details->is_thumbnailing &&