app/actions, menus: Add 'Select Layers' option

This patch adds an option to create a selection covering
just the area of the highlighted layers. This differs from
the Select All option, as it will not expand if you switch
layers.

app/actions/select-actions.c

@@ -46,6 +46,12 @@ static const GimpActionEntry select_actions[] =
     select_all_cmd_callback,
     GIMP_HELP_SELECTION_ALL },
 
+  { "select-layers", NULL,
+    NC_("select-action", "_Layers"), NULL, { "<shift>A", NULL },
+    NC_("select-action", "Select all highlighted layers"),
+    select_layer_cmd_callback,
+    GIMP_HELP_SELECTION_LAYERS },
+
   { "select-none", GIMP_ICON_SELECTION_NONE,
     NC_("select-action", "_None"), NULL, { "<primary><shift>A", NULL },
     NC_("select-action", "Dismiss the selection"),
@@ -186,6 +192,7 @@ select_actions_update (GimpActionGroup *group,
         gimp_action_group_set_action_sensitive (group, action, (condition) != 0, NULL)
 
   SET_SENSITIVE ("select-all",    image && ! sel_all);
+  SET_SENSITIVE ("select-layers", image && ! sel_all);
   SET_SENSITIVE ("select-none",   image && sel);
   SET_SENSITIVE ("select-invert", image);
 

app/actions/select-commands.c

@@ -30,6 +30,7 @@
 
 #include "core/gimp.h"
 #include "core/gimpchannel.h"
+#include "core/gimpchannel-combine.h"
 #include "core/gimpimage.h"
 #include "core/gimpselection.h"
 
@@ -88,6 +89,42 @@ select_all_cmd_callback (GimpAction *action,
   gimp_image_flush (image);
 }
 
+void
+select_layer_cmd_callback (GimpAction *action,
+                           GVariant   *value,
+                           gpointer    data)
+{
+  GimpChannelOps ops;
+  GimpImage     *image;
+  GimpItem      *item;
+  GList         *iter;
+  GList         *layers;
+
+  return_if_no_image (image, data);
+
+  ops = GIMP_CHANNEL_OP_REPLACE;
+  layers = gimp_image_get_selected_layers (image);
+
+  if (g_list_length (layers) > 0)
+    gimp_channel_push_undo (gimp_image_get_mask (image),
+                            C_("undo-type", "Select Layers"));
+
+  for (iter = layers; iter; iter = iter->next)
+    {
+      item = GIMP_ITEM (iter->data);
+      gimp_channel_combine_rect (gimp_image_get_mask (image),
+                                 ops,
+                                 gimp_item_get_offset_x (item),
+                                 gimp_item_get_offset_y (item),
+                                 gimp_item_get_width (item),
+                                 gimp_item_get_height (item));
+
+      ops = GIMP_CHANNEL_OP_ADD;
+    }
+
+  gimp_image_flush (image);
+}
+
 void
 select_none_cmd_callback (GimpAction *action,
                           GVariant   *value,

app/actions/select-commands.h

@@ -21,6 +21,9 @@
 void   select_all_cmd_callback              (GimpAction *action,
                                              GVariant   *value,
                                              gpointer    data);
+void   select_layer_cmd_callback            (GimpAction *action,
+                                             GVariant   *value,
+                                             gpointer    data);
 void   select_none_cmd_callback             (GimpAction *action,
                                              GVariant   *value,
                                              gpointer    data);

app/widgets/gimphelp-ids.h

@@ -69,6 +69,7 @@
 
 #define GIMP_HELP_SELECTION_DIALOG                "gimp-selection-dialog"
 #define GIMP_HELP_SELECTION_ALL                   "gimp-selection-all"
+#define GIMP_HELP_SELECTION_LAYERS                "gimp-selection-layers"
 #define GIMP_HELP_SELECTION_NONE                  "gimp-selection-none"
 #define GIMP_HELP_SELECTION_INVERT                "gimp-selection-invert"
 #define GIMP_HELP_SELECTION_FLOAT                 "gimp-selection-float"

menus/image-menu.ui.in.in

@@ -149,6 +149,7 @@
       <attribute name="label" translatable="yes" context="select-action">_Select</attribute>
       <section>
         <item><attribute name="action">app.select-all</attribute></item>
+        <item><attribute name="action">app.select-layers</attribute></item>
         <item><attribute name="action">app.select-none</attribute></item>
         <item><attribute name="action">app.select-invert</attribute></item>
         <submenu>

menus/selection-menu.ui

@@ -7,6 +7,7 @@
       <attribute name="icon">gimp-selection</attribute>
 
       <item><attribute name="action">app.select-all</attribute></item>
+      <item><attribute name="action">app.select-layers</attribute></item>
       <item><attribute name="action">app.select-none</attribute></item>
       <item><attribute name="action">app.select-invert</attribute></item>
       <item><attribute name="action">app.paths-selection-from-paths</attribute></item>