[gnome-control-center/wip/jsparber/background: 8/29] background: expand thumbnails to fill a gallery row

[Julian Sparber <jsparber src gnome org>]

commit 4f1e2a70c88c7f2432e5905da37768e48e43c5b7
Author: Julian Sparber <julian sparber net>
Date:   Sat Nov 11 21:33:07 2017 +0100

    background: expand thumbnails to fill a gallery row
    
    - change gallery wallpaper size
    - use same margin size everywhere around the flowbox
    
    https://bugzilla.gnome.org/show_bug.cgi?id=788515

 panels/background/background.ui         |  9 +++---
 panels/background/cc-background-panel.c | 51 ++++++++++++++++-----------------
 2 files changed, 28 insertions(+), 32 deletions(-)
---
diff --git a/panels/background/background.ui b/panels/background/background.ui
index db3793cb1..dc40911b0 100644
--- a/panels/background/background.ui
+++ b/panels/background/background.ui
@@ -138,18 +138,17 @@
                   <object class="GtkFlowBox" id="background-gallery">
                     <property name="visible">True</property>
                     <property name="can_focus">False</property>
-
-        <property name="expand">True</property>
+                    <property name="hexpand">True</property>
+                    <property name="vexpand">False</property>
                     <property name="homogeneous">True</property>
                     <property name="orientation">horizontal</property>
                     <property name="min-children-per-line">2</property>
+                    <property name="max-children-per-line">1000</property>
                     <property name="row_spacing">5</property>
                     <property name="column_spacing">5</property>
                     <property name="halign">fill</property>
                     <property name="valign">fill</property>
                     <property name="margin">25</property>
-                    <property name="margin_top">50</property>
-                    <property name="margin_bottom">32</property>
                   </object>
                 </child>
                 <child>
@@ -159,7 +158,7 @@
                     <property name="halign">center</property>
                     <property name="valign">end</property>
                     <property name="margin">32</property>
-                    <property name="margin_top">0</property>
+                    <property name="margin_top">7</property>
                     <property name="orientation">vertical</property>
                     <property name="spacing">16</property>
                     <child>
diff --git a/panels/background/cc-background-panel.c b/panels/background/cc-background-panel.c
index bb9d0bbcf..dd76ab0c0 100644
--- a/panels/background/cc-background-panel.c
+++ b/panels/background/cc-background-panel.c
@@ -335,16 +335,30 @@ on_gallery_item_draw (GtkWidget         *widget,
                       cairo_t           *cr,
                       GdkPixbuf *pixbuf)
 {
-  const gint width = gtk_widget_get_allocated_width (gtk_widget_get_parent (widget));
-  const gint height = gtk_widget_get_allocated_height (gtk_widget_get_parent (widget));
+  const gint space_width = gtk_widget_get_allocated_width (widget);
+  const gint space_height = gtk_widget_get_allocated_height ( (widget));
+  const gint pixbuf_width = gdk_pixbuf_get_width (pixbuf);
+  const gint pixbuf_height = gdk_pixbuf_get_height (pixbuf);
+  gint new_width;
+  gint new_height;
+
+  if (space_width * 9/16 > space_height) {
+    new_width = space_width;
+    new_height = space_width * 9/16;
+  }
+  else {
+    new_width = space_height * 16/9;
+    new_height = space_height;
+  }
 
   pixbuf = gdk_pixbuf_scale_simple (pixbuf,
-                                    width,
-                                    height,
+                                    new_width,
+                                    new_height,
                                     GDK_INTERP_BILINEAR);
+
   gdk_cairo_set_source_pixbuf (cr,
                                pixbuf,
-                               0, 0);
+                               -(new_width - space_width)/2, -(new_height - space_height)/2);
   cairo_paint (cr);
 
   return TRUE;
@@ -894,8 +908,8 @@ create_gallery_item (gpointer item,
   GdkPixbuf *pixbuf;
   CcBackgroundItem *self = item;
   gint scale_factor;
-  const gint preview_width = 400;//panel->gallery_size;//309;
-  const gint preview_height = 400 * 9 / 16; //panel->gallery_size * 9/16;//168;
+  const gint preview_width = 800;//panel->gallery_size;//309;
+  const gint preview_height = 800 * 9 / 16; //panel->gallery_size * 9/16;//168;
 
   scale_factor = gtk_widget_get_scale_factor (GTK_WIDGET (panel));
 
@@ -909,38 +923,21 @@ create_gallery_item (gpointer item,
   if (cc_background_item_changes_with_time (self)) {
     add_slideshow_emblem (pixbuf, scale_factor);
   }
-  //widget = gtk_image_new_from_pixbuf (pixbuf);
   widget = gtk_drawing_area_new ();
-  gtk_widget_set_size_request (widget, 200, 200 * 9/16);
+  gtk_widget_set_size_request (widget, 250, 250 * 9/16);
   gtk_widget_set_hexpand(widget, TRUE);
   gtk_widget_set_vexpand(widget, TRUE);
   g_signal_connect (G_OBJECT (widget), "draw",
                     G_CALLBACK (on_gallery_item_draw), pixbuf);
 
   flow = cc_background_grid_item_new(self);
+
+  gtk_widget_set_size_request (flow, 250, 200);
   cc_background_grid_item_set_ref (flow, self);
   gtk_widget_show (flow);
   gtk_widget_show (widget);
-  /*frame = gtk_aspect_frame_new (NULL,
-    0.5,
-    0.5,
-    1.7777,
-    FALSE);
-
-    gtk_widget_set_size_request (frame, preview_width, -1);
-    gtk_frame_set_shadow_type (frame,
-    GTK_SHADOW_NONE);
-    gtk_container_add (GTK_CONTAINER (frame), widget);
-
-
-    gtk_widget_show (frame);
-    gtk_container_add (GTK_CONTAINER (flow), frame);
-
-*/
-
   gtk_container_add (GTK_CONTAINER (flow), widget);
 
-
   return flow;
 }