d3d11: implement mouse wheel events

Adittion of d3d11 support for WM_MOUSEWHEEL and WM_MOUSEHWHEEL events,
which are triggered when the mouse is scrolled vertically or horizontally
respectively.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7705>

subprojects/gst-plugins-bad/sys/d3d11/gstd3d11videosink.cpp

@@ -1212,6 +1212,27 @@ gst_d3d11_video_sink_mouse_event (GstD3D11Window * window, const gchar * event,
   gst_navigation_send_event_simple (GST_NAVIGATION (self), mouse_event);
 }
 
+static void
+gst_d3d11_video_sink_mouse_scroll_event (GstD3D11Window * window,
+    const gchar * event, gdouble x, gdouble y, gint delta_x, gint delta_y,
+    guint modifier, GstD3D11VideoSink * self)
+{
+  GstEvent *mouse_event;
+
+  if (!self->enable_navigation_events || !event)
+    return;
+
+  GST_LOG_OBJECT (self, "send mouse scroll event %s,", event);
+  if (g_strcmp0 ("mouse-scroll", event) == 0) {
+    mouse_event = gst_navigation_event_new_mouse_scroll (x, y, delta_x,
+        delta_y, (GstNavigationModifierType) modifier);
+  } else {
+    return;
+  }
+
+  gst_navigation_send_event_simple (GST_NAVIGATION (self), mouse_event);
+}
+
 static void
 gst_d3d11_video_sink_present (GstD3D11Window * window, GstD3D11Device * device,
     ID3D11RenderTargetView * rtv, GstD3D11VideoSink * self)
@@ -1329,6 +1350,8 @@ done:
       G_CALLBACK (gst_d3d11_video_sink_key_event), self);
   g_signal_connect (self->window, "mouse-event",
       G_CALLBACK (gst_d3d11_video_sink_mouse_event), self);
+  g_signal_connect (self->window, "mouse-scroll-event",
+      G_CALLBACK (gst_d3d11_video_sink_mouse_scroll_event), self);
   g_signal_connect (self->window, "present",
       G_CALLBACK (gst_d3d11_video_sink_present), self);
 

subprojects/gst-plugins-bad/sys/d3d11/gstd3d11window.cpp

@@ -67,6 +67,7 @@ enum
 {
   SIGNAL_KEY_EVENT,
   SIGNAL_MOUSE_EVENT,
+  SIGNAL_MOUSE_SCROLL_EVENT,
   SIGNAL_PRESENT,
   SIGNAL_LAST
 };
@@ -181,6 +182,12 @@ gst_d3d11_window_class_init (GstD3D11WindowClass * klass)
       G_TYPE_NONE, 5, G_TYPE_STRING, G_TYPE_INT, G_TYPE_DOUBLE, G_TYPE_DOUBLE,
       G_TYPE_UINT);
 
+  d3d11_window_signals[SIGNAL_MOUSE_SCROLL_EVENT] =
+      g_signal_new ("mouse-scroll-event", G_TYPE_FROM_CLASS (klass),
+      G_SIGNAL_RUN_LAST, 0, NULL, NULL, NULL,
+      G_TYPE_NONE, 6, G_TYPE_STRING, G_TYPE_DOUBLE, G_TYPE_DOUBLE,
+      G_TYPE_INT, G_TYPE_INT, G_TYPE_UINT);
+
   d3d11_window_signals[SIGNAL_PRESENT] =
       g_signal_new ("present", G_TYPE_FROM_CLASS (klass),
       G_SIGNAL_RUN_LAST, 0, nullptr, nullptr, nullptr,
@@ -571,6 +578,20 @@ gst_d3d11_window_on_mouse_event (GstD3D11Window * window, const gchar * event,
       event, button, x, y, modifier);
 }
 
+void
+gst_d3d11_window_on_mouse_scroll_event (GstD3D11Window * window,
+    const gchar * event, gdouble x, gdouble y, gint delta_x, gint delta_y,
+    guint modifier)
+{
+  g_return_if_fail (GST_IS_D3D11_WINDOW (window));
+
+  if (!window->enable_navigation_events)
+    return;
+
+  g_signal_emit (window, d3d11_window_signals[SIGNAL_MOUSE_SCROLL_EVENT], 0,
+      event, x, y, delta_x, delta_y, modifier);
+}
+
 typedef struct
 {
   DXGI_FORMAT dxgi_format;

subprojects/gst-plugins-bad/sys/d3d11/gstd3d11window.h

@@ -235,6 +235,14 @@ void          gst_d3d11_window_on_mouse_event       (GstD3D11Window * window,
                                                      gdouble y,
                                                      guint modifier);
 
+void          gst_d3d11_window_on_mouse_scroll_event (GstD3D11Window * window,
+                                                     const gchar * event,
+                                                     gdouble x,
+                                                     gdouble y,
+                                                     gint delta_x,
+                                                     gint delta_y,
+                                                     guint modifier);
+
 /* utils */
 GstD3D11WindowNativeType gst_d3d11_window_get_native_type_from_handle (guintptr handle);
 

subprojects/gst-plugins-bad/sys/d3d11/gstd3d11window_win32.cpp

@@ -733,6 +733,8 @@ gst_d3d11_window_win32_on_mouse_event (GstD3D11WindowWin32 * self,
   gint button;
   const gchar *event = nullptr;
   guint modifier = 0;
+  gint delta_x = 0, delta_y = 0;
+  POINT screen_point = { 0, 0 };
 
   if (!window->enable_navigation_events)
     return;
@@ -778,6 +780,16 @@ gst_d3d11_window_win32_on_mouse_event (GstD3D11WindowWin32 * self,
       button = 3;
       event = "mouse-double-click";
       break;
+    case WM_MOUSEHWHEEL:
+      button = 0;
+      event = "mouse-scroll";
+      delta_x = GET_WHEEL_DELTA_WPARAM (wParam);
+      break;
+    case WM_MOUSEWHEEL:
+      button = 0;
+      event = "mouse-scroll";
+      delta_y = GET_WHEEL_DELTA_WPARAM (wParam);
+      break;
     default:
       return;
   }
@@ -793,10 +805,20 @@ gst_d3d11_window_win32_on_mouse_event (GstD3D11WindowWin32 * self,
   if ((wParam & MK_SHIFT) != 0)
     modifier |= GST_NAVIGATION_MODIFIER_SHIFT_MASK;
 
+  if (uMsg == WM_MOUSEHWHEEL || uMsg == WM_MOUSEWHEEL) {
+    screen_point.x = GET_X_LPARAM (lParam);
+    screen_point.y = GET_Y_LPARAM (lParam);
+    ScreenToClient (hWnd, &screen_point);
+
+    gst_d3d11_window_on_mouse_scroll_event (window, event,
+        (gdouble) screen_point.x, (gdouble) screen_point.y,
+        delta_x, delta_y, modifier);
+  } else {
     gst_d3d11_window_on_mouse_event (window,
         event, button, (gdouble) GET_X_LPARAM (lParam),
         (gdouble) GET_Y_LPARAM (lParam), modifier);
   }
+}
 
 static void
 gst_d3d11_window_win32_handle_window_proc (GstD3D11WindowWin32 * self,
@@ -831,6 +853,8 @@ gst_d3d11_window_win32_handle_window_proc (GstD3D11WindowWin32 * self,
     case WM_LBUTTONDBLCLK:
     case WM_RBUTTONDBLCLK:
     case WM_MBUTTONDBLCLK:
+    case WM_MOUSEWHEEL:
+    case WM_MOUSEHWHEEL:
       gst_d3d11_window_win32_on_mouse_event (self, hWnd, uMsg, wParam, lParam);
       break;
     case WM_SYSKEYDOWN: