[gtk+/wip/hires-icons: 3/8] iconfactory: Add _scaled() variants

[Carlos Garnacho <carlosg src gnome org>]

commit 40b1e920e8dd1a5532b834589025186028314f7c
Author: Carlos Garnacho <carlosg gnome org>
Date:   Tue Feb 12 13:59:09 2013 +0100

    iconfactory: Add _scaled() variants
    
    These functions can be used to deal with stock icons
    at sizes that are suitable for gdk_window_get_scale_factor()

 gtk/gtkiconfactory.c  |  136 ++++++++++++++++++++++++++++++++++++-------------
 gtk/gtkstylecontext.h |    5 ++
 2 files changed, 105 insertions(+), 36 deletions(-)
---
diff --git a/gtk/gtkiconfactory.c b/gtk/gtkiconfactory.c
index 7cc1af9..4183baf 100644
--- a/gtk/gtkiconfactory.c
+++ b/gtk/gtkiconfactory.c
@@ -934,6 +934,7 @@ icon_sizes_init_for_settings (GtkSettings *settings)
 static gboolean
 icon_size_lookup_intern (GtkSettings *settings,
                         GtkIconSize  size,
+                         gdouble      scale,
                         gint        *widthp,
                         gint        *heightp)
 {
@@ -973,10 +974,16 @@ icon_size_lookup_intern (GtkSettings *settings,
     }
 
   if (widthp)
-    *widthp = width_for_settings >= 0 ? width_for_settings : icon_sizes[size].width;
+    {
+      *widthp = width_for_settings >= 0 ? width_for_settings : icon_sizes[size].width;
+      (*widthp) *= scale;
+    }
 
   if (heightp)
-    *heightp = height_for_settings >= 0 ? height_for_settings : icon_sizes[size].height;
+    {
+      *heightp = height_for_settings >= 0 ? height_for_settings : icon_sizes[size].height;
+      (*heightp) *= scale;
+    }
 
   return TRUE;
 }
@@ -1012,7 +1019,7 @@ gtk_icon_size_lookup_for_settings (GtkSettings *settings,
 {
   g_return_val_if_fail (GTK_IS_SETTINGS (settings), FALSE);
 
-  return icon_size_lookup_intern (settings, size, width, height);
+  return icon_size_lookup_intern (settings, size, 1, width, height);
 }
 
 /**
@@ -1047,6 +1054,18 @@ gtk_icon_size_lookup (GtkIconSize  size,
                                            size, widthp, heightp);
 }
 
+gboolean
+gtk_icon_size_lookup_scaled (GtkSettings *settings,
+                             GtkIconSize  size,
+                             gdouble      scale,
+                             gint        *width,
+                             gint        *height)
+{
+  g_return_val_if_fail (GTK_IS_SETTINGS (settings), FALSE);
+
+  return icon_size_lookup_intern (settings, size, scale, width, height);
+}
+
 static GtkIconSize
 icon_size_register_intern (const gchar *name,
                           gint         width,
@@ -1133,7 +1152,7 @@ gtk_icon_size_register_alias (const gchar *alias,
 
   init_icon_sizes ();
 
-  if (!icon_size_lookup_intern (NULL, target, NULL, NULL))
+  if (!icon_size_lookup_intern (NULL, target, 1, NULL, NULL))
     g_warning ("gtk_icon_size_register_alias: Icon size %u does not exist", target);
 
   ia = g_hash_table_lookup (icon_aliases, alias);
@@ -1412,8 +1431,8 @@ sizes_equivalent (GtkIconSize lhs,
 
   gint r_w, r_h, l_w, l_h;
 
-  icon_size_lookup_intern (NULL, rhs, &r_w, &r_h);
-  icon_size_lookup_intern (NULL, lhs, &l_w, &l_h);
+  icon_size_lookup_intern (NULL, rhs, 1, &r_w, &r_h);
+  icon_size_lookup_intern (NULL, lhs, 1, &l_w, &l_h);
 
   return r_w == l_w && r_h == l_h;
 #endif
@@ -1492,7 +1511,8 @@ ensure_filename_pixbuf (GtkIconSet    *icon_set,
 static GdkPixbuf *
 render_icon_name_pixbuf (GtkIconSource    *icon_source,
                         GtkStyleContext  *context,
-                        GtkIconSize       size)
+                        GtkIconSize       size,
+                         gboolean          scale_requested)
 {
   GdkPixbuf *pixbuf;
   GdkPixbuf *tmp_pixbuf;
@@ -1503,11 +1523,20 @@ render_icon_name_pixbuf (GtkIconSource    *icon_source,
   gint width, height, pixel_size;
   gint *sizes, *s, dist;
   GError *error = NULL;
+  gdouble scale = 1;
 
   screen = gtk_style_context_get_screen (context);
   icon_theme = gtk_icon_theme_get_for_screen (screen);
   settings = gtk_settings_get_for_screen (screen);
 
+  if (scale_requested && widget)
+    {
+      if (!widget->window)
+        gtk_widget_realize (widget);
+
+      scale = gdk_window_get_scale_factor (widget->window);
+    }
+
   if (!gtk_icon_size_lookup_for_settings (settings, size, &width, &height))
     {
       if (size == (GtkIconSize)-1)
@@ -1550,7 +1579,7 @@ render_icon_name_pixbuf (GtkIconSource    *icon_source,
        }
     }
 
-  pixel_size = MIN (width, height);
+  pixel_size = MIN (width, height) * scale;
 
   if (icon_source->direction != GTK_TEXT_DIR_NONE)
     {
@@ -1610,7 +1639,8 @@ find_and_render_icon_source (GtkIconSet       *icon_set,
                             GtkStyleContext  *context,
                             GtkTextDirection  direction,
                             GtkStateType      state,
-                            GtkIconSize       size)
+                            GtkIconSize       size,
+                             gboolean          scale_requested)
 {
   GSList *failed = NULL;
   GdkPixbuf *pixbuf = NULL;
@@ -1648,7 +1678,8 @@ find_and_render_icon_source (GtkIconSet       *icon_set,
          break;
        case GTK_ICON_SOURCE_ICON_NAME:
        case GTK_ICON_SOURCE_STATIC_ICON_NAME:
-          pixbuf = render_icon_name_pixbuf (source, context, size);
+          pixbuf = render_icon_name_pixbuf (source, context,
+                                            size, scale_requested);
          if (!pixbuf)
            failed = g_slist_prepend (failed, source);
          break;
@@ -1692,37 +1723,33 @@ render_fallback_image (GtkStyleContext   *context,
   return gtk_render_icon_pixbuf (context, &fallback_source, size);
 }
 
-/**
- * gtk_icon_set_render_icon_pixbuf:
- * @icon_set: a #GtkIconSet
- * @context: a #GtkStyleContext
- * @size: (type int): icon size. A size of (GtkIconSize)-1
- *        means render at the size of the source and don't scale.
- *
- * Renders an icon using gtk_render_icon_pixbuf(). In most cases,
- * gtk_widget_render_icon_pixbuf() is better, since it automatically provides
- * most of the arguments from the current widget settings.  This
- * function never returns %NULL; if the icon can't be rendered
- * (perhaps because an image file fails to load), a default "missing
- * image" icon will be returned instead.
- *
- * Return value: (transfer full): a #GdkPixbuf to be displayed
- *
- * Since: 3.0
- */
-GdkPixbuf *
-gtk_icon_set_render_icon_pixbuf (GtkIconSet        *icon_set,
-                                 GtkStyleContext   *context,
-                                 GtkIconSize        size)
+static gdouble
+_get_real_scale (GtkStyleContext *context,
+                 GtkIconSize      size,
+                 GdkPixbuf       *icon)
+{
+  GtkSettings *settings;
+  GdkScreen *screen;
+  gint icon_width;
+
+  screen = gtk_style_context_get_screen (context);
+  settings = gtk_settings_get_for_screen (screen);
+  gtk_icon_size_lookup_for_settings (settings, size, &icon_width, NULL);
+
+  return (gdouble) gdk_pixbuf_get_width (icon) / icon_width;
+}
+
+GdkPixbuf*
+gtk_icon_set_render_icon_pixbuf_scaled (GtkIconSet      *icon_set,
+                                        GtkStyleContext *context,
+                                        GtkIconSize      size,
+                                        gboolean        *scale)
 {
   GdkPixbuf *icon = NULL;
   GtkStateFlags flags = 0;
   GtkStateType state;
   GtkTextDirection direction;
 
-  g_return_val_if_fail (icon_set != NULL, NULL);
-  g_return_val_if_fail (GTK_IS_STYLE_CONTEXT (context), NULL);
-
   flags = gtk_style_context_get_state (context);
   if (flags & GTK_STATE_FLAG_INSENSITIVE)
     state = GTK_STATE_INSENSITIVE;
@@ -1741,22 +1768,59 @@ G_GNUC_END_IGNORE_DEPRECATIONS;
       if (icon)
         {
           g_object_ref (icon);
+
+          if (scale)
+            *scale = _get_real_scale (context, size, icon);
+
           return icon;
         }
     }
 
   if (icon_set->sources)
-    icon = find_and_render_icon_source (icon_set, context, direction, state, size);
+    icon = find_and_render_icon_source (icon_set, context, direction, state,
+                                        size, (scale != NULL));
 
   if (icon == NULL)
     icon = render_fallback_image (context, direction, state, size);
 
   add_to_cache (icon_set, context, direction, state, size, icon);
 
+  if (scale)
+    *scale = _get_real_scale (context, size, icon);
+
   return icon;
 }
 
 /**
+ * gtk_icon_set_render_icon_pixbuf:
+ * @icon_set: a #GtkIconSet
+ * @context: a #GtkStyleContext
+ * @size: (type int): icon size. A size of (GtkIconSize)-1
+ *        means render at the size of the source and don't scale.
+ *
+ * Renders an icon using gtk_render_icon_pixbuf(). In most cases,
+ * gtk_widget_render_icon_pixbuf() is better, since it automatically provides
+ * most of the arguments from the current widget settings.  This
+ * function never returns %NULL; if the icon can't be rendered
+ * (perhaps because an image file fails to load), a default "missing
+ * image" icon will be returned instead.
+ *
+ * Return value: (transfer full): a #GdkPixbuf to be displayed
+ *
+ * Since: 3.0
+ */
+GdkPixbuf *
+gtk_icon_set_render_icon_pixbuf (GtkIconSet        *icon_set,
+                                 GtkStyleContext   *context,
+                                 GtkIconSize        size)
+{
+  g_return_val_if_fail (icon_set != NULL, NULL);
+  g_return_val_if_fail (GTK_IS_STYLE_CONTEXT (context), NULL);
+
+  return gtk_icon_set_render_icon_scaled (icon_set, context, size, NULL);
+}
+
+/**
  * gtk_icon_set_render_icon:
  * @icon_set: a #GtkIconSet
  * @style: (allow-none): a #GtkStyle associated with @widget, or %NULL
diff --git a/gtk/gtkstylecontext.h b/gtk/gtkstylecontext.h
index 26709a1..09e0aee 100644
--- a/gtk/gtkstylecontext.h
+++ b/gtk/gtkstylecontext.h
@@ -861,6 +861,11 @@ GDK_AVAILABLE_IN_ALL
 GdkPixbuf  * gtk_icon_set_render_icon_pixbuf   (GtkIconSet      *icon_set,
                                                 GtkStyleContext *context,
                                                 GtkIconSize      size);
+GdkPixbuf  *
+        gtk_icon_set_render_icon_pixbuf_scaled (GtkIconSet      *icon_set,
+                                                GtkStyleContext *context,
+                                                GtkIconSize      size,
+                                                gdouble         *scale);
 
 GDK_AVAILABLE_IN_ALL
 void        gtk_style_context_set_screen (GtkStyleContext *context,