[gimp/metadata-browser] Bug 663121 - guides are below rotate/transform/shear/perspective preview

[Roman Joost <romanofski src gnome org>]

commit 4798a48500ceb5ae5c72bfa89242b59ac9c1defa
Author: Michael Natterer <mitch gimp org>
Date:   Wed Nov 16 21:32:29 2011 +0100

    Bug 663121 - guides are below rotate/transform/shear/perspective preview
    
    Add a canvas item group for previews, and a small preview infrastructure
    to GimpDrawTool, and put the transform preview into the preview group,
    which is below all guides, grid and layer boundaries.

 app/display/gimpdisplayshell-items.c |   26 ++++++++++++++
 app/display/gimpdisplayshell-items.h |   29 +++++++++-------
 app/display/gimpdisplayshell.h       |    1 +
 app/tools/gimpdrawtool.c             |   60 +++++++++++++++++++++++++++------
 app/tools/gimpdrawtool.h             |    6 +++
 5 files changed, 99 insertions(+), 23 deletions(-)
---
diff --git a/app/display/gimpdisplayshell-items.c b/app/display/gimpdisplayshell-items.c
index 3500984..9cb1261 100644
--- a/app/display/gimpdisplayshell-items.c
+++ b/app/display/gimpdisplayshell-items.c
@@ -55,6 +55,10 @@ gimp_display_shell_items_init (GimpDisplayShell *shell)
   gimp_display_shell_add_item (shell, shell->passe_partout);
   g_object_unref (shell->passe_partout);
 
+  shell->preview_items = gimp_canvas_group_new (shell);
+  gimp_display_shell_add_item (shell, shell->preview_items);
+  g_object_unref (shell->preview_items);
+
   shell->vectors = gimp_canvas_proxy_group_new (shell);
   gimp_display_shell_add_item (shell, shell->vectors);
   g_object_unref (shell->vectors);
@@ -107,11 +111,13 @@ gimp_display_shell_items_free (GimpDisplayShell *shell)
       shell->canvas_item = NULL;
 
       shell->passe_partout  = NULL;
+      shell->preview_items  = NULL;
       shell->vectors        = NULL;
       shell->grid           = NULL;
       shell->guides         = NULL;
       shell->sample_points  = NULL;
       shell->layer_boundary = NULL;
+      shell->tool_items     = NULL;
       shell->cursor         = NULL;
     }
 }
@@ -137,6 +143,26 @@ gimp_display_shell_remove_item (GimpDisplayShell *shell,
 }
 
 void
+gimp_display_shell_add_preview_item (GimpDisplayShell *shell,
+                                     GimpCanvasItem   *item)
+{
+  g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell));
+  g_return_if_fail (GIMP_IS_CANVAS_ITEM (item));
+
+  gimp_canvas_group_add_item (GIMP_CANVAS_GROUP (shell->preview_items), item);
+}
+
+void
+gimp_display_shell_remove_preview_item (GimpDisplayShell *shell,
+                                        GimpCanvasItem   *item)
+{
+  g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell));
+  g_return_if_fail (GIMP_IS_CANVAS_ITEM (item));
+
+  gimp_canvas_group_remove_item (GIMP_CANVAS_GROUP (shell->preview_items), item);
+}
+
+void
 gimp_display_shell_add_tool_item (GimpDisplayShell *shell,
                                   GimpCanvasItem   *item)
 {
diff --git a/app/display/gimpdisplayshell-items.h b/app/display/gimpdisplayshell-items.h
index 61f5f34..5a2a792 100644
--- a/app/display/gimpdisplayshell-items.h
+++ b/app/display/gimpdisplayshell-items.h
@@ -22,18 +22,23 @@
 #define __GIMP_DISPLAY_SHELL_ITEMS_H__
 
 
-void   gimp_display_shell_items_init       (GimpDisplayShell *shell);
-void   gimp_display_shell_items_free       (GimpDisplayShell *shell);
-
-void   gimp_display_shell_add_item         (GimpDisplayShell *shell,
-                                            GimpCanvasItem   *item);
-void   gimp_display_shell_remove_item      (GimpDisplayShell *shell,
-                                            GimpCanvasItem   *item);
-
-void   gimp_display_shell_add_tool_item    (GimpDisplayShell *shell,
-                                            GimpCanvasItem   *item);
-void   gimp_display_shell_remove_tool_item (GimpDisplayShell *shell,
-                                            GimpCanvasItem   *item);
+void   gimp_display_shell_items_init          (GimpDisplayShell *shell);
+void   gimp_display_shell_items_free          (GimpDisplayShell *shell);
+
+void   gimp_display_shell_add_item            (GimpDisplayShell *shell,
+                                               GimpCanvasItem   *item);
+void   gimp_display_shell_remove_item         (GimpDisplayShell *shell,
+                                               GimpCanvasItem   *item);
+
+void   gimp_display_shell_add_preview_item    (GimpDisplayShell *shell,
+                                               GimpCanvasItem   *item);
+void   gimp_display_shell_remove_preview_item (GimpDisplayShell *shell,
+                                               GimpCanvasItem   *item);
+
+void   gimp_display_shell_add_tool_item       (GimpDisplayShell *shell,
+                                               GimpCanvasItem   *item);
+void   gimp_display_shell_remove_tool_item    (GimpDisplayShell *shell,
+                                               GimpCanvasItem   *item);
 
 
 #endif /* __GIMP_DISPLAY_SHELL_ITEMS_H__ */
diff --git a/app/display/gimpdisplayshell.h b/app/display/gimpdisplayshell.h
index a780849..01822b6 100644
--- a/app/display/gimpdisplayshell.h
+++ b/app/display/gimpdisplayshell.h
@@ -120,6 +120,7 @@ struct _GimpDisplayShell
 
   GimpCanvasItem    *canvas_item;      /*  items drawn on the canvas          */
   GimpCanvasItem    *passe_partout;    /*  item for the highlight             */
+  GimpCanvasItem    *preview_items;    /*  item for previews                  */
   GimpCanvasItem    *vectors;          /*  item proxy of vectors              */
   GimpCanvasItem    *grid;             /*  item proxy of the grid             */
   GimpCanvasItem    *guides;           /*  item proxies of guides             */
diff --git a/app/tools/gimpdrawtool.c b/app/tools/gimpdrawtool.c
index 09dd7d5..8eefd73 100644
--- a/app/tools/gimpdrawtool.c
+++ b/app/tools/gimpdrawtool.c
@@ -103,6 +103,7 @@ gimp_draw_tool_init (GimpDrawTool *draw_tool)
 {
   draw_tool->display      = NULL;
   draw_tool->paused_count = 0;
+  draw_tool->preview      = NULL;
   draw_tool->item         = NULL;
 }
 
@@ -193,6 +194,8 @@ gimp_draw_tool_draw (GimpDrawTool *draw_tool)
       draw_tool->paused_count == 0 &&
       ! draw_tool->draw_timeout)
     {
+      GimpDisplayShell *shell = gimp_display_get_shell (draw_tool->display);
+
       gimp_draw_tool_undraw (draw_tool);
 
       GIMP_DRAW_TOOL_GET_CLASS (draw_tool)->draw (draw_tool);
@@ -208,25 +211,34 @@ gimp_draw_tool_draw (GimpDrawTool *draw_tool)
             gimp_draw_tool_pop_group (draw_tool);
         }
 
-      if (draw_tool->item)
-        {
-          GimpDisplayShell *shell = gimp_display_get_shell (draw_tool->display);
+      if (draw_tool->preview)
+        gimp_display_shell_add_preview_item (shell, draw_tool->preview);
 
-          gimp_display_shell_add_tool_item (shell, draw_tool->item);
-        }
+      if (draw_tool->item)
+        gimp_display_shell_add_tool_item (shell, draw_tool->item);
     }
 }
 
 static void
 gimp_draw_tool_undraw (GimpDrawTool *draw_tool)
 {
-  if (draw_tool->display && draw_tool->item)
+  if (draw_tool->display)
     {
       GimpDisplayShell *shell = gimp_display_get_shell (draw_tool->display);
 
-      gimp_display_shell_remove_tool_item (shell, draw_tool->item);
-      g_object_unref (draw_tool->item);
-      draw_tool->item = NULL;
+      if (draw_tool->preview)
+        {
+          gimp_display_shell_remove_preview_item (shell, draw_tool->preview);
+          g_object_unref (draw_tool->preview);
+          draw_tool->preview = NULL;
+        }
+
+      if (draw_tool->item)
+        {
+          gimp_display_shell_remove_tool_item (shell, draw_tool->item);
+          g_object_unref (draw_tool->item);
+          draw_tool->item = NULL;
+        }
     }
 }
 
@@ -374,6 +386,31 @@ gimp_draw_tool_calc_distance_square (GimpDrawTool *draw_tool,
 }
 
 void
+gimp_draw_tool_add_preview (GimpDrawTool   *draw_tool,
+                            GimpCanvasItem *item)
+{
+  g_return_if_fail (GIMP_IS_DRAW_TOOL (draw_tool));
+  g_return_if_fail (GIMP_IS_CANVAS_ITEM (item));
+
+  if (! draw_tool->preview)
+    draw_tool->preview =
+      gimp_canvas_group_new (gimp_display_get_shell (draw_tool->display));
+
+  gimp_canvas_group_add_item (GIMP_CANVAS_GROUP (draw_tool->preview), item);
+}
+
+void
+gimp_draw_tool_remove_preview (GimpDrawTool   *draw_tool,
+                               GimpCanvasItem *item)
+{
+  g_return_if_fail (GIMP_IS_DRAW_TOOL (draw_tool));
+  g_return_if_fail (GIMP_IS_CANVAS_ITEM (item));
+  g_return_if_fail (draw_tool->preview != NULL);
+
+  gimp_canvas_group_remove_item (GIMP_CANVAS_GROUP (draw_tool->preview), item);
+}
+
+void
 gimp_draw_tool_add_item (GimpDrawTool   *draw_tool,
                          GimpCanvasItem *item)
 {
@@ -383,7 +420,8 @@ gimp_draw_tool_add_item (GimpDrawTool   *draw_tool,
   g_return_if_fail (GIMP_IS_CANVAS_ITEM (item));
 
   if (! draw_tool->item)
-    draw_tool->item = gimp_canvas_group_new (gimp_display_get_shell (draw_tool->display));
+    draw_tool->item =
+      gimp_canvas_group_new (gimp_display_get_shell (draw_tool->display));
 
   group = GIMP_CANVAS_GROUP (draw_tool->item);
 
@@ -911,7 +949,7 @@ gimp_draw_tool_add_transform_preview (GimpDrawTool      *draw_tool,
                                             x1, y1, x2, y2,
                                             perspective, opacity);
 
-  gimp_draw_tool_add_item (draw_tool, item);
+  gimp_draw_tool_add_preview (draw_tool, item);
   g_object_unref (item);
 
   return item;
diff --git a/app/tools/gimpdrawtool.h b/app/tools/gimpdrawtool.h
index b968ffe..705fae6 100644
--- a/app/tools/gimpdrawtool.h
+++ b/app/tools/gimpdrawtool.h
@@ -49,6 +49,7 @@ struct _GimpDrawTool
   gint            paused_count; /*  count to keep track of multiple pauses  */
   guint           draw_timeout; /*  draw delay timeout ID                   */
 
+  GimpCanvasItem *preview;
   GimpCanvasItem *item;
   GList          *group_stack;
 };
@@ -87,6 +88,11 @@ gdouble          gimp_draw_tool_calc_distance_square (GimpDrawTool     *draw_too
                                                       gdouble           x2,
                                                       gdouble           y2);
 
+void             gimp_draw_tool_add_preview          (GimpDrawTool     *draw_tool,
+                                                      GimpCanvasItem   *item);
+void             gimp_draw_tool_remove_preview       (GimpDrawTool     *draw_tool,
+                                                      GimpCanvasItem   *item);
+
 void             gimp_draw_tool_add_item             (GimpDrawTool     *draw_tool,
                                                       GimpCanvasItem   *item);
 void             gimp_draw_tool_remove_item          (GimpDrawTool     *draw_tool,