[gnome-software] Show a blurred low-resolution screenshot while loading the HiDPI one

[Richard Hughes <rhughes src gnome org>]

commit bc8ba3c22cd87dfb074ba5fb187e66fa79f9b1b8
Author: Richard Hughes <richard hughsie com>
Date:   Fri Oct 24 13:50:20 2014 +0100

    Show a blurred low-resolution screenshot while loading the HiDPI one
    
    Resolves: https://bugzilla.gnome.org/show_bug.cgi?id=738854

 configure.ac              |    2 +-
 src/gs-screenshot-image.c |   55 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 56 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 5470f81..4f1557d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -61,7 +61,7 @@ dnl - Check library dependencies
 dnl ---------------------------------------------------------------------------
 PKG_CHECK_MODULES(GTK, gtk+-3.0 >= 3.14.1 gio-unix-2.0)
 PKG_CHECK_MODULES(PACKAGEKIT, packagekit-glib2 >= 1.0.0)
-PKG_CHECK_MODULES(APPSTREAM, appstream-glib >= 0.2.4)
+PKG_CHECK_MODULES(APPSTREAM, appstream-glib >= 0.3.2)
 PKG_CHECK_MODULES(SQLITE, sqlite3)
 PKG_CHECK_MODULES(SOUP, libsoup-2.4)
 PKG_CHECK_MODULES(GSETTINGS_DESKTOP_SCHEMAS, gsettings-desktop-schemas >= 3.11.5)
diff --git a/src/gs-screenshot-image.c b/src/gs-screenshot-image.c
index bd81053..a96b993 100644
--- a/src/gs-screenshot-image.c
+++ b/src/gs-screenshot-image.c
@@ -193,6 +193,46 @@ as_screenshot_show_image (GsScreenshotImage *ssimg)
 }
 
 /**
+ * gs_screenshot_image_show_blurred:
+ **/
+static void
+gs_screenshot_image_show_blurred (GsScreenshotImage *ssimg,
+                                 const gchar *filename_thumb)
+{
+       AsImage *im;
+       GdkPixbuf *pb = NULL;
+       GsScreenshotImagePrivate *priv;
+       gboolean ret;
+
+       priv = gs_screenshot_image_get_instance_private (ssimg);
+
+       /* create an helper which can do the blurring for us */
+       im = as_image_new ();
+       ret = as_image_load_filename (im, filename_thumb, NULL);
+       if (!ret)
+               goto out;
+       pb = as_image_save_pixbuf (im,
+                                  priv->width * priv->scale,
+                                  priv->height * priv->scale,
+                                  AS_IMAGE_SAVE_FLAG_BLUR);
+       if (pb == NULL)
+               goto out;
+
+       if (g_strcmp0 (priv->current_image, "image1") == 0) {
+               gs_image_set_from_pixbuf_with_scale (GTK_IMAGE (priv->image1),
+                                                    pb, priv->scale);
+       } else {
+               gs_image_set_from_pixbuf_with_scale (GTK_IMAGE (priv->image2),
+                                                    pb, priv->scale);
+       }
+out:
+       if (im != NULL)
+               g_object_unref (im);
+       if (pb != NULL)
+               g_object_unref (pb);
+}
+
+/**
  * gs_screenshot_image_complete_cb:
  **/
 static void
@@ -339,6 +379,7 @@ gs_screenshot_image_load_async (GsScreenshotImage *ssimg,
        const gchar *url;
        gchar *basename = NULL;
        gchar *cachedir = NULL;
+       gchar *cachedir2 = NULL;
        gchar *sizedir = NULL;
        gint rc;
 
@@ -399,6 +440,19 @@ gs_screenshot_image_load_async (GsScreenshotImage *ssimg,
                goto out;
        }
 
+       /* can we load a blurred smaller version of this straight away */
+       if (priv->width > AS_IMAGE_THUMBNAIL_WIDTH &&
+           priv->height > AS_IMAGE_THUMBNAIL_HEIGHT) {
+               cachedir2 = g_build_filename (priv->cachedir,
+                                             "gnome-software",
+                                             "screenshots",
+                                             "112x63",
+                                             basename,
+                                             NULL);
+               if (g_file_test (cachedir2, G_FILE_TEST_EXISTS))
+                       gs_screenshot_image_show_blurred (ssimg, cachedir2);
+       }
+
        /* download file */
        g_debug ("downloading %s to %s", url, priv->filename);
        base_uri = soup_uri_new (url);
@@ -423,6 +477,7 @@ out:
        g_free (basename);
        g_free (sizedir);
        g_free (cachedir);
+       g_free (cachedir2);
        if (base_uri != NULL)
                soup_uri_free (base_uri);
 }