tools: allow on-canvas text editor to move

This commit implements the ability to freely move the on-canvas
text editor across the screen by introducing a drag-and-drop mechanism.

app/display/gimpdisplayshell.c

@@ -1365,6 +1365,11 @@ gimp_display_shell_transform_overlay (GimpDisplayShell *shell,
       *x -= requisition.width + overlay->spacing_x;
       *y -= requisition.height / 2;
       break;
+
+    default:
+      *x -= overlay->spacing_x;
+      *y -= overlay->spacing_y;
+      break;
     }
 }
 

app/tools/gimptexttool-editor.c

@@ -128,6 +128,20 @@ static void   gimp_text_tool_fix_position         (GimpTextTool    *text_tool,
 static void   gimp_text_tool_convert_gdkkeyevent  (GimpTextTool    *text_tool,
                                                    GdkEventKey     *kevent);
 
+static gboolean gimp_text_tool_style_overlay_button_press
+                                                  (GtkWidget       *widget,
+                                                   GdkEventButton  *event,
+                                                   gpointer         user_data);
+static gboolean gimp_text_tool_style_overlay_button_release
+                                                  (GtkWidget       *widget,
+                                                   GdkEventButton  *event,
+                                                   gpointer         user_data);
+static gboolean gimp_text_tool_style_overlay_button_motion
+                                                  (GtkWidget       *widget,
+                                                   GdkEventMotion  *event,
+                                                   gpointer         user_data);
+
+#define DEFAULT_DRAG_OFFSET 25
 
 /*  public functions  */
 
@@ -214,6 +228,23 @@ gimp_text_tool_editor_start (GimpTextTool *text_tool)
       gimp_overlay_box_set_child_opacity (GIMP_OVERLAY_BOX (shell->canvas),
                                           text_tool->style_overlay, 0.85);
 
+      gtk_widget_add_events (text_tool->style_overlay,
+                             (GDK_BUTTON_PRESS_MASK   |
+                              GDK_BUTTON_RELEASE_MASK |
+                              GDK_BUTTON_MOTION_MASK));
+
+      g_signal_connect_object (text_tool->style_overlay, "button-press-event",
+                               G_CALLBACK (gimp_text_tool_style_overlay_button_press),
+                               text_tool, 0);
+      g_signal_connect_object (text_tool->style_overlay, "button-release-event",
+                               G_CALLBACK (gimp_text_tool_style_overlay_button_release),
+                               text_tool, 0);
+      g_signal_connect_object (text_tool->style_overlay, "motion-notify-event",
+                               G_CALLBACK (gimp_text_tool_style_overlay_button_motion),
+                               text_tool, 0);
+
+      text_tool->overlay_dragging = FALSE;
+
       if (text_tool->image)
         gimp_image_get_resolution (text_tool->image, &xres, &yres);
 
@@ -1893,3 +1924,89 @@ gimp_text_tool_convert_gdkkeyevent (GimpTextTool *text_tool,
       break;
     }
 }
+
+static gboolean
+gimp_text_tool_style_overlay_button_press (GtkWidget      *widget,
+                                           GdkEventButton *event,
+                                           gpointer        user_data)
+{
+  GimpTextTool     *text_tool    = GIMP_TEXT_TOOL (user_data);
+  GtkWidget        *event_widget = gtk_get_event_widget ((GdkEvent*) event);
+
+  if (event_widget != GTK_WIDGET (text_tool->style_overlay) &&
+      gtk_widget_is_ancestor (event_widget, GTK_WIDGET (text_tool->style_editor)))
+    {
+      return FALSE;
+    }
+
+  if (gtk_widget_get_window (GTK_WIDGET (text_tool->style_overlay)))
+    {
+      GdkCursor *cursor = gdk_cursor_new_for_display (gtk_widget_get_display (GTK_WIDGET (text_tool->style_overlay)),
+                                                      GDK_FLEUR);
+      if (cursor)
+        {
+          gdk_window_set_cursor (gtk_widget_get_window (GTK_WIDGET (text_tool->style_overlay)),
+                                 cursor);
+          g_object_unref (cursor);
+        }
+    }
+
+  text_tool->overlay_dragging = TRUE;
+  text_tool->drag_offset_x    = event->x;
+  text_tool->drag_offset_y    = event->y;
+
+  return TRUE;
+}
+
+static gboolean
+gimp_text_tool_style_overlay_button_release (GtkWidget      *widget,
+                                             GdkEventButton *event,
+                                             gpointer        user_data)
+{
+  GimpTextTool *text_tool    = GIMP_TEXT_TOOL (user_data);
+  GtkWidget    *event_widget = gtk_get_event_widget ((GdkEvent*) event);
+
+  if (event_widget != GTK_WIDGET (text_tool->style_overlay) &&
+      gtk_widget_is_ancestor (event_widget, GTK_WIDGET (text_tool->style_editor)))
+    {
+      return FALSE;
+    }
+
+  text_tool->overlay_dragging = FALSE;
+
+  if (gtk_widget_get_window (GTK_WIDGET (text_tool->style_overlay)))
+    gdk_window_set_cursor (gtk_widget_get_window (GTK_WIDGET (text_tool->style_overlay)), NULL);
+
+  return TRUE;
+}
+
+static gboolean
+gimp_text_tool_style_overlay_button_motion (GtkWidget      *widget,
+                                            GdkEventMotion *event,
+                                            gpointer        user_data)
+{
+  GimpTextTool *text_tool = GIMP_TEXT_TOOL (user_data);
+
+  if (text_tool->overlay_dragging)
+    {
+      GimpTool         *tool  = GIMP_TOOL (text_tool);
+      GimpDisplayShell *shell = gimp_display_get_shell (tool->display);
+      gdouble           x, y;
+
+      gdk_window_get_device_position_double (gtk_widget_get_window (GTK_WIDGET (shell)),
+                                             event->device,
+                                             &x, &y, NULL);
+
+      gimp_display_shell_untransform_xy_f (shell,
+                                           x, y,
+                                           &x, &y);
+
+      gimp_display_shell_move_overlay (shell,
+                                       text_tool->style_overlay,
+                                       x, y, -1,
+                                       text_tool->drag_offset_x + DEFAULT_DRAG_OFFSET,
+                                       text_tool->drag_offset_y + DEFAULT_DRAG_OFFSET);
+    }
+
+  return TRUE;
+}

app/tools/gimptexttool.h

@@ -71,6 +71,12 @@ struct _GimpTextTool
   GtkWidget      *style_overlay;
   GtkWidget      *style_editor;
 
+  /* style overlay dragging: */
+
+  gboolean        overlay_dragging;
+  gdouble         drag_offset_x;
+  gdouble         drag_offset_y;
+
   gboolean        selecting;
   GtkTextIter     select_start_iter;
   gboolean        select_words;

app/widgets/gimpoverlayframe.c

@@ -36,7 +36,7 @@ static gboolean   gimp_overlay_frame_draw (GtkWidget *widget,
                                            cairo_t   *cr);
 
 
-G_DEFINE_TYPE (GimpOverlayFrame, gimp_overlay_frame, GTK_TYPE_BIN)
+G_DEFINE_TYPE (GimpOverlayFrame, gimp_overlay_frame, GTK_TYPE_EVENT_BOX)
 
 #define parent_class gimp_overlay_frame_parent_class
 

app/widgets/gimpoverlayframe.h

@@ -35,12 +35,12 @@ typedef struct _GimpOverlayFrameClass GimpOverlayFrameClass;
 
 struct _GimpOverlayFrame
 {
-  GtkBin  parent_instance;
+  GtkEventBox  parent_instance;
 };
 
 struct _GimpOverlayFrameClass
 {
-  GtkBinClass  parent_class;
+  GtkEventBoxClass  parent_class;
 };