[gtk/wip/chergert/quartz4u] macos: add helper to synthesize motion

[Christian Hergert <chergert src gnome org>]

commit b19a54b673208e013472d4b532e6835142dcbf39
Author: Christian Hergert <chergert redhat com>
Date:   Thu May 7 16:51:26 2020 -0700

    macos: add helper to synthesize motion

 gdk/macos/gdkmacosdisplay-private.h   |  2 ++
 gdk/macos/gdkmacosdisplay-translate.c | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+)
---
diff --git a/gdk/macos/gdkmacosdisplay-private.h b/gdk/macos/gdkmacosdisplay-private.h
index 2530339e66..6d31144415 100644
--- a/gdk/macos/gdkmacosdisplay-private.h
+++ b/gdk/macos/gdkmacosdisplay-private.h
@@ -62,6 +62,8 @@ void             _gdk_macos_display_add_frame_callback             (GdkMacosDisp
                                                                     GdkMacosSurface *surface);
 void             _gdk_macos_display_remove_frame_callback          (GdkMacosDisplay *self,
                                                                     GdkMacosSurface *surface);
+void             _gdk_macos_display_synthesize_motion              (GdkMacosDisplay *self,
+                                                                    GdkMacosSurface *surface);
 
 G_END_DECLS
 
diff --git a/gdk/macos/gdkmacosdisplay-translate.c b/gdk/macos/gdkmacosdisplay-translate.c
index d0eb822c7d..ae5abb7a7b 100644
--- a/gdk/macos/gdkmacosdisplay-translate.c
+++ b/gdk/macos/gdkmacosdisplay-translate.c
@@ -813,3 +813,37 @@ _gdk_macos_display_translate (GdkMacosDisplay *self,
   return ret;
 }
 
+void
+_gdk_macos_display_synthesize_motion (GdkMacosDisplay *self,
+                                      GdkMacosSurface *surface)
+{
+  GdkModifierType state;
+  GdkEvent *event;
+  GdkSeat *seat;
+  NSPoint point;
+  GList *node;
+  int x;
+  int y;
+
+  g_return_if_fail (GDK_IS_MACOS_DISPLAY (self));
+  g_return_if_fail (GDK_IS_MACOS_SURFACE (surface));
+
+  seat = gdk_display_get_default_seat (GDK_DISPLAY (self));
+  point = [NSEvent mouseLocation];
+  _gdk_macos_display_from_display_coords (self, point.x, point.y, &x, &y);
+
+  state = _gdk_macos_display_get_current_keyboard_modifiers (self) |
+          _gdk_macos_display_get_current_mouse_modifiers (self);
+
+  event = gdk_motion_event_new (GDK_SURFACE (surface),
+                                gdk_seat_get_pointer (seat),
+                                NULL,
+                                NULL,
+                                get_time_from_ns_event ([NSApp currentEvent]),
+                                state,
+                                x,
+                                y,
+                                NULL);
+  node = _gdk_event_queue_append (GDK_DISPLAY (self), event);
+  _gdk_windowing_got_event (GDK_DISPLAY (self), node, event, 0);
+}