[gimp] app, devel-docs: bumping the XCF version to 17.

[Jehan <jehanp src gnome org>]

commit aa3808addfe05bf34cad23309badc87912abd93d
Author: Jehan <jehan girinstud io>
Date:   Tue Feb 15 21:58:47 2022 +0100

    app, devel-docs: bumping the XCF version to 17.
    
    XCF 17 includes the new visibility locks and the ability to add position
    and alpha locks on layer groups.
    I am going to push the various commits implementing these different
    features together which is why we gather them as a single XCF version.

 app/core/gimpimage.c              | 44 ++++++++++++++++++++++++++++++++++-----
 app/xcf/xcf.c                     |  3 ++-
 devel-docs/specifications/xcf.txt | 11 ++++++++++
 3 files changed, 52 insertions(+), 6 deletions(-)
---
diff --git a/app/core/gimpimage.c b/app/core/gimpimage.c
index 487391bb98..a9126ab31f 100644
--- a/app/core/gimpimage.c
+++ b/app/core/gimpimage.c
@@ -2697,7 +2697,7 @@ gimp_image_get_xcf_version (GimpImage    *image,
                             const gchar **version_string,
                             gchar       **version_reason)
 {
-  GList       *layers;
+  GList       *items;
   GList       *list;
   GList       *reasons = NULL;
   gint         version = 0;  /* default to oldest */
@@ -2715,9 +2715,8 @@ gimp_image_get_xcf_version (GimpImage    *image,
   if (gimp_image_get_colormap (image))
     version = 1;
 
-  layers = gimp_image_get_layer_list (image);
-
-  for (list = layers; list; list = g_list_next (list))
+  items = gimp_image_get_layer_list (image);
+  for (list = items; list; list = g_list_next (list))
     {
       GimpLayer *layer = GIMP_LAYER (list->data);
 
@@ -2836,10 +2835,44 @@ gimp_image_get_xcf_version (GimpImage    *image,
                                              "added in %s"), "GIMP 2.10"));
               version = MAX (13, version);
             }
+
+          if (gimp_item_get_lock_position (GIMP_ITEM (layer)))
+            {
+              ADD_REASON (g_strdup_printf (_("Position locks on layer groups were added in %s"),
+                                           "GIMP 3.0"));
+              version = MAX (17, version);
+            }
+
+          if (gimp_layer_get_lock_alpha (layer))
+            {
+              ADD_REASON (g_strdup_printf (_("Alpha channel locks on layer groups were added in %s"),
+                                           "GIMP 3.0"));
+              version = MAX (17, version);
+            }
+        }
+
+      if (gimp_item_get_lock_visibility (GIMP_ITEM (layer)))
+        {
+          ADD_REASON (g_strdup_printf (_("Visibility locks were added in %s"),
+                                       "GIMP 3.0"));
+          version = MAX (17, version);
         }
     }
+  g_list_free (items);
 
-  g_list_free (layers);
+  items = gimp_image_get_channel_list (image);
+  for (list = items; list; list = g_list_next (list))
+    {
+      GimpChannel *channel = GIMP_CHANNEL (list->data);
+
+      if (gimp_item_get_lock_visibility (GIMP_ITEM (channel)))
+        {
+          ADD_REASON (g_strdup_printf (_("Visibility locks were added in %s"),
+                                       "GIMP 3.0"));
+          version = MAX (17, version);
+        }
+    }
+  g_list_free (items);
 
   /* version 6 for new metadata has been dropped since they are
    * saved through parasites, which is compatible with older versions.
@@ -2960,6 +2993,7 @@ gimp_image_get_xcf_version (GimpImage    *image,
     case 14:
     case 15:
     case 16:
+    case 17:
       if (gimp_version)   *gimp_version   = 300;
       if (version_string) *version_string = "GIMP 3.0";
       break;
diff --git a/app/xcf/xcf.c b/app/xcf/xcf.c
index 3db206c6f4..5509e54a8a 100644
--- a/app/xcf/xcf.c
+++ b/app/xcf/xcf.c
@@ -84,7 +84,8 @@ static GimpXcfLoaderFunc * const xcf_loaders[] =
   xcf_load_image,   /* version 13 */
   xcf_load_image,   /* version 14 */
   xcf_load_image,   /* version 15 */
-  xcf_load_image    /* version 16 */
+  xcf_load_image,   /* version 16 */
+  xcf_load_image,   /* version 17 */
 };
 
 
diff --git a/devel-docs/specifications/xcf.txt b/devel-docs/specifications/xcf.txt
index 9b17f92739..4900bc7c7d 100644
--- a/devel-docs/specifications/xcf.txt
+++ b/devel-docs/specifications/xcf.txt
@@ -194,6 +194,11 @@ Since GIMP 3.0.0, released on TODO.
 - New PROP_ITEM_SET and PROP_ITEM_SET_ITEM to store sets of layers,
   channels or paths.
 
+Version 17:
+Since GIMP 3.0.0, released on TODO.
+- New PROP_LOCK_VISIBILITY on layers and channels.
+- PROP_LOCK_POSITION and PROP_LOCK_ALPHA can now be set on layer groups.
+
 1. BASIC CONCEPTS
 =================
 
@@ -670,6 +675,9 @@ PROP_LOCK_POSITION (since GIMP 2.10.0, commit d4933b30526, editing state)
   PROP_LOCK_POSITION specifies whether the layer, channel or path's
   position is locked, i.e. cannot be transformed (translation, etc.).
 
+  Up to XCF 16, this could not be set on layer groups. It is possible
+  since XCF 17.
+
 PROP_LOCK_VISIBILITY (since version 3, editing state)
   uint32  42         Type identification
   uint32  4          Four bytes of payload
@@ -1374,6 +1382,9 @@ PROP_LOCK_ALPHA (editing state)
   PROP_LOCK_ALPHA prevents all drawing tools in GIMP from increasing the alpha
   of any pixel in the layer. Decreasing the alpha is possible.
 
+  Up to XCF 16, this could not be set on layer groups. It is possible
+  since XCF 17.
+
 PROP_MODE (essential)
   uint32  7        Type identification
   uint32  4        Four bytes of payload