[gimp] tools: Rectangle select. Incorrect center_xy after converting channel selection to rectangle

[Jehan <jehanp src gnome org>]

commit 695942660316347a5f1546da1c32bcce6fed2c56
Author: Stanislav Grinkov <43956-stanislavgrinkov users noreply gitlab gnome org>
Date:   Wed Feb 24 20:57:09 2021 +0600

    tools: Rectangle select. Incorrect center_xy after converting channel selection to rectangle
    
    Was caused by widget tool fixed_center_x and fixed_center_y coordinates set to
    coordinates of mouse click instead of rectangle center after converting channel
    selection bbox to rectangle.
    
    Now rectangle fixed_center_x and fixed_center_y coordinates are always updated
    when tool widget x1, x2, y1, or y2 coordinates are updated.
    
    Closes #6487

 app/display/gimptoolrectangle.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)
---
diff --git a/app/display/gimptoolrectangle.c b/app/display/gimptoolrectangle.c
index e55f6d6c76..1c39e37b90 100644
--- a/app/display/gimptoolrectangle.c
+++ b/app/display/gimptoolrectangle.c
@@ -431,6 +431,8 @@ static void     gimp_tool_rectangle_adjust_coord    (GimpToolRectangle     *rect
                                                      gdouble                coord_y_input,
                                                      gdouble               *coord_x_output,
                                                      gdouble               *coord_y_output);
+static void     gimp_tool_rectangle_recalculate_center_xy
+                                                    (GimpToolRectangle     *rectangle);
 
 
 G_DEFINE_TYPE_WITH_PRIVATE (GimpToolRectangle, gimp_tool_rectangle,
@@ -1058,6 +1060,8 @@ gimp_tool_rectangle_notify (GObject    *object,
     {
       gimp_tool_rectangle_update_int_rect (rectangle);
 
+      gimp_tool_rectangle_recalculate_center_xy (rectangle);
+
       gimp_tool_rectangle_update_options (rectangle);
     }
   else if (! strcmp  (pspec->name, "x") &&
@@ -1546,8 +1550,7 @@ gimp_tool_rectangle_button_release (GimpToolWidget        *widget,
     }
 
   /* We must update this. */
-  private->center_x_on_fixed_center = (private->x1 + private->x2) / 2;
-  private->center_y_on_fixed_center = (private->y1 + private->y2) / 2;
+  gimp_tool_rectangle_recalculate_center_xy (rectangle);
 
   gimp_tool_rectangle_update_options (rectangle);
 
@@ -1824,8 +1827,7 @@ gimp_tool_rectangle_key_press (GimpToolWidget *widget,
 
   gimp_tool_rectangle_update_with_coord (rectangle, new_x, new_y);
 
-  private->center_x_on_fixed_center = (private->x1 + private->x2) / 2;
-  private->center_y_on_fixed_center = (private->y1 + private->y2) / 2;
+  gimp_tool_rectangle_recalculate_center_xy (rectangle);
 
   gimp_tool_rectangle_update_options (rectangle);
 
@@ -2189,8 +2191,7 @@ gimp_tool_rectangle_synthesize_motion (GimpToolRectangle *rectangle,
   gimp_tool_rectangle_update_with_coord (rectangle, new_x, new_y);
 
   /* We must update this. */
-  private->center_x_on_fixed_center = (private->x1 + private->x2) / 2;
-  private->center_y_on_fixed_center = (private->y1 + private->y2) / 2;
+  gimp_tool_rectangle_recalculate_center_xy (rectangle);
 
   gimp_tool_rectangle_update_options (rectangle);
 
@@ -3858,6 +3859,15 @@ gimp_tool_rectangle_adjust_coord (GimpToolRectangle *rectangle,
     }
 }
 
+static void
+gimp_tool_rectangle_recalculate_center_xy (GimpToolRectangle *rectangle)
+{
+  GimpToolRectanglePrivate *private = rectangle->private;
+
+  private->center_x_on_fixed_center = (private->x1 + private->x2) / 2;
+  private->center_y_on_fixed_center = (private->y1 + private->y2) / 2;
+}
+
 
 /*  public functions  */