From 21a8f9c96b7ef37c1f30f5a9c78dea49a92d14e0 Mon Sep 17 00:00:00 2001
From: Michael Natterer <mitch@gimp.org>
Date: Wed, 11 Jun 2014 21:33:57 +0200
Subject: [PATCH] app: add boolean "mask_inverted" to GimpDisplayShell

and to gimp_display_shell_set_mask(). It allows to choose whether the
mask is drawn inverted, instead of always drawing it inverted.
---
 app/display/gimpdisplayshell-render.c | 25 +++++++++++++------------
 app/display/gimpdisplayshell.c        | 11 +++++++----
 app/display/gimpdisplayshell.h        |  4 +++-
 app/tools/gimpforegroundselecttool.c  |  6 +++---
 4 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/app/display/gimpdisplayshell-render.c b/app/display/gimpdisplayshell-render.c
index 8956f2883f..cab202f495 100644
--- a/app/display/gimpdisplayshell-render.c
+++ b/app/display/gimpdisplayshell-render.c
@@ -205,8 +205,6 @@ gimp_display_shell_render (GimpDisplayShell *shell,
 
   if (shell->mask)
     {
-      gint mask_height;
-
       if (! shell->mask_surface)
         {
           shell->mask_surface =
@@ -231,21 +229,24 @@ gimp_display_shell_render (GimpDisplayShell *shell,
                        data, stride,
                        GEGL_ABYSS_CLAMP);
 
-      /* invert the mask so what is *not* the foreground object is masked */
-      mask_height = scaled_height;
-      while (mask_height--)
+      if (shell->mask_inverted)
         {
-          gint    mask_width = scaled_width;
-          guchar *d          = data;
+          gint mask_height = scaled_height;
 
-          while (mask_width--)
+          while (mask_height--)
             {
-              guchar inv = 255 - *d;
+              gint    mask_width = scaled_width;
+              guchar *d          = data;
 
-              *d++ = inv;
+              while (mask_width--)
+                {
+                  guchar inv = 255 - *d;
+
+                  *d++ = inv;
+                }
+
+              data += stride;
             }
-
-          data += stride;
         }
     }
 
diff --git a/app/display/gimpdisplayshell.c b/app/display/gimpdisplayshell.c
index d66a87db5c..b174a5ac1a 100644
--- a/app/display/gimpdisplayshell.c
+++ b/app/display/gimpdisplayshell.c
@@ -1918,15 +1918,16 @@ gimp_display_shell_set_highlight (GimpDisplayShell   *shell,
  * @shell: a #GimpDisplayShell
  * @mask:  a #GimpDrawable (1 byte per pixel)
  * @color: the color to use for drawing the mask
+ * @inverted: #TRUE if the mask should be drawn inverted
  *
- * Previews a selection (used by the foreground selection tool).
- * Pixels that are not selected (> 127) in the mask are tinted with
- * the given color.
+ * Previews an image-sized mask. Depending on @inverted, pixels that
+ * are selected or not selected are tinted with the given color.
  **/
 void
 gimp_display_shell_set_mask (GimpDisplayShell *shell,
                              GeglBuffer       *mask,
-                             const GimpRGB    *color)
+                             const GimpRGB    *color,
+                             gboolean          inverted)
 {
   g_return_if_fail (GIMP_IS_DISPLAY_SHELL (shell));
   g_return_if_fail (mask == NULL || GEGL_IS_BUFFER (mask));
@@ -1943,5 +1944,7 @@ gimp_display_shell_set_mask (GimpDisplayShell *shell,
   if (mask)
     shell->mask_color = *color;
 
+  shell->mask_inverted = inverted;
+
   gimp_display_shell_expose_full (shell);
 }
diff --git a/app/display/gimpdisplayshell.h b/app/display/gimpdisplayshell.h
index d459b8a739..b49e02c1fc 100644
--- a/app/display/gimpdisplayshell.h
+++ b/app/display/gimpdisplayshell.h
@@ -191,6 +191,7 @@ struct _GimpDisplayShell
 
   GeglBuffer        *mask;
   GimpRGB            mask_color;
+  gboolean           mask_inverted;
 
   GimpMotionBuffer  *motion_buffer;
 
@@ -281,7 +282,8 @@ void              gimp_display_shell_set_highlight (GimpDisplayShell   *shell,
                                                     const GdkRectangle *highlight);
 void              gimp_display_shell_set_mask      (GimpDisplayShell   *shell,
                                                     GeglBuffer         *mask,
-                                                    const GimpRGB      *color);
+                                                    const GimpRGB      *color,
+                                                    gboolean            inverted);
 
 
 #endif /* __GIMP_DISPLAY_SHELL_H__ */
diff --git a/app/tools/gimpforegroundselecttool.c b/app/tools/gimpforegroundselecttool.c
index 7f5d8b1bcd..372a7158d1 100644
--- a/app/tools/gimpforegroundselecttool.c
+++ b/app/tools/gimpforegroundselecttool.c
@@ -944,7 +944,7 @@ gimp_foreground_select_tool_halt (GimpForegroundSelectTool *fg_select)
 
   if (tool->display)
     gimp_display_shell_set_mask (gimp_display_get_shell (tool->display),
-                                 NULL, NULL);
+                                 NULL, NULL, FALSE);
 
   gimp_tool_control_set_tool_cursor        (tool->control,
                                             GIMP_TOOL_CURSOR_FREE_SELECT);
@@ -1006,7 +1006,7 @@ gimp_foreground_select_tool_set_trimap (GimpForegroundSelectTool *fg_select)
 
   gimp_foreground_select_options_get_mask_color (options, &color);
   gimp_display_shell_set_mask (gimp_display_get_shell (tool->display),
-                               fg_select->trimap, &color);
+                               fg_select->trimap, &color, TRUE);
 
   gimp_tool_control_set_tool_cursor        (tool->control,
                                             GIMP_TOOL_CURSOR_PAINTBRUSH);
@@ -1034,7 +1034,7 @@ gimp_foreground_select_tool_set_preview (GimpForegroundSelectTool *fg_select)
 
   gimp_foreground_select_options_get_mask_color (options, &color);
   gimp_display_shell_set_mask (gimp_display_get_shell (tool->display),
-                               fg_select->mask, &color);
+                               fg_select->mask, &color, TRUE);
 
   gimp_tool_control_set_tool_cursor        (tool->control,
                                             GIMP_TOOL_CURSOR_PAINTBRUSH);