compositor: send translated navigation events to the relevant sink pads

Fixes #888

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1495>

subprojects/gst-plugins-base/gst/compositor/compositor.c

@@ -422,6 +422,15 @@ _mixer_pad_get_output_size (GstCompositor * comp, GstCompositorPad * comp_pad,
   *height = pad_height;
 }
 
+static gboolean
+is_point_contained (const GstVideoRectangle rect, const gint px, const gint py)
+{
+  if ((px >= rect.x) && (px <= rect.x + rect.w) &&
+      (py >= rect.y) && (py <= rect.y + rect.h))
+    return TRUE;
+  return FALSE;
+}
+
 /* Test whether rectangle2 contains rectangle 1 (geometrically) */
 static gboolean
 is_rectangle_contained (const GstVideoRectangle rect1,
@@ -1512,6 +1521,79 @@ gst_compositor_release_pad (GstElement * element, GstPad * pad)
   GST_ELEMENT_CLASS (parent_class)->release_pad (element, pad);
 }
 
+static gboolean
+src_pad_mouse_event (GstElement * element, GstPad * pad, gpointer user_data)
+{
+  GstVideoAggregator *vagg = GST_VIDEO_AGGREGATOR_CAST (element);
+  GstCompositor *comp = GST_COMPOSITOR (element);
+  GstCompositorPad *cpad = GST_COMPOSITOR_PAD (pad);
+  GstStructure *st =
+      gst_structure_copy (gst_event_get_structure (GST_EVENT_CAST (user_data)));
+  gdouble event_x, event_y;
+  gint offset_x, offset_y;
+  GstVideoRectangle rect;
+
+  gst_structure_get (st, "pointer_x", G_TYPE_DOUBLE, &event_x,
+      "pointer_y", G_TYPE_DOUBLE, &event_y, NULL);
+
+  /* Find output rectangle of this pad */
+  _mixer_pad_get_output_size (comp, cpad,
+      GST_VIDEO_INFO_PAR_N (&vagg->info),
+      GST_VIDEO_INFO_PAR_D (&vagg->info),
+      &(rect.w), &(rect.h), &offset_x, &offset_y);
+  rect.x = cpad->xpos + offset_x;
+  rect.y = cpad->ypos + offset_y;
+
+  /* Translate coordinates and send event if it lies in this rectangle */
+  if (is_point_contained (rect, event_x, event_y)) {
+    GstVideoAggregatorPad *vpad = GST_VIDEO_AGGREGATOR_PAD_CAST (cpad);
+    gdouble w, h, x, y;
+
+    w = (gdouble) GST_VIDEO_INFO_WIDTH (&vpad->info);
+    h = (gdouble) GST_VIDEO_INFO_HEIGHT (&vpad->info);
+    x = (event_x - (gdouble) rect.x) * (w / (gdouble) rect.w);
+    y = (event_y - (gdouble) rect.y) * (h / (gdouble) rect.h);
+
+    gst_structure_set (st, "pointer_x", G_TYPE_DOUBLE, x,
+        "pointer_y", G_TYPE_DOUBLE, y, NULL);
+    gst_pad_push_event (pad, gst_event_new_navigation (st));
+  } else {
+    gst_structure_free (st);
+  }
+
+  return TRUE;
+}
+
+static gboolean
+_src_event (GstAggregator * agg, GstEvent * event)
+{
+  GstNavigationEventType event_type;
+
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_NAVIGATION:
+    {
+      event_type = gst_navigation_event_get_type (event);
+      switch (event_type) {
+        case GST_NAVIGATION_EVENT_MOUSE_BUTTON_PRESS:
+        case GST_NAVIGATION_EVENT_MOUSE_BUTTON_RELEASE:
+        case GST_NAVIGATION_EVENT_MOUSE_MOVE:
+        case GST_NAVIGATION_EVENT_MOUSE_SCROLL:
+          gst_element_foreach_sink_pad (GST_ELEMENT_CAST (agg),
+              src_pad_mouse_event, event);
+          gst_event_unref (event);
+          return TRUE;
+
+        default:
+          break;
+      }
+    }
+    default:
+      break;
+  }
+
+  return GST_AGGREGATOR_CLASS (parent_class)->src_event (agg, event);
+}
+
 static gboolean
 _sink_query (GstAggregator * agg, GstAggregatorPad * bpad, GstQuery * query)
 {
@@ -1585,6 +1667,7 @@ gst_compositor_class_init (GstCompositorClass * klass)
   gstelement_class->release_pad =
       GST_DEBUG_FUNCPTR (gst_compositor_release_pad);
   agg_class->sink_query = _sink_query;
+  agg_class->src_event = _src_event;
   agg_class->fixate_src_caps = _fixate_caps;
   agg_class->negotiated_src_caps = _negotiated_caps;
   videoaggregator_class->aggregate_frames = gst_compositor_aggregate_frames;

subprojects/gst-plugins-base/tests/check/elements/compositor.c

@@ -280,6 +280,145 @@ GST_START_TEST (test_event)
 
 GST_END_TEST;
 
+typedef struct _ProbeEvent
+{
+  gboolean received;
+  gdouble x_pos, y_pos;
+} ProbeEvent;
+
+static GstPadProbeReturn
+probe_nav_event (GstPad * pad, GstPadProbeInfo * info, gpointer user_data)
+{
+  GstEvent *event = gst_pad_probe_info_get_event (info);
+  ProbeEvent *probe_ev = (ProbeEvent *) user_data;
+
+  if (GST_EVENT_TYPE (event) == GST_EVENT_NAVIGATION) {
+    probe_ev->received = TRUE;
+    gst_navigation_event_parse_mouse_move_event (event,
+        &(probe_ev->x_pos), &(probe_ev->y_pos));
+  }
+
+  return GST_PAD_PROBE_OK;
+}
+
+GST_START_TEST (test_navigation_events)
+{
+  GstElement *bin, *src1, *src2, *src3, *filter1, *filter2, *filter3;
+  GstElement *compositor, *sink;
+  GstPad *srcpad, *sinkpad;
+  GstCaps *caps;
+  gboolean res;
+  ProbeEvent probe_events[3];
+  GstStateChangeReturn state_res;
+  GstEvent *event;
+
+  GST_INFO ("preparing test");
+
+  /* build pipeline */
+  bin = gst_pipeline_new ("pipeline");
+  src1 = gst_element_factory_make ("videotestsrc", "src1");
+  src2 = gst_element_factory_make ("videotestsrc", "src2");
+  src3 = gst_element_factory_make ("videotestsrc", "src3");
+  filter1 = gst_element_factory_make ("capsfilter", "filter1");
+  filter2 = gst_element_factory_make ("capsfilter", "filter2");
+  filter3 = gst_element_factory_make ("capsfilter", "filter3");
+  compositor = gst_element_factory_make ("compositor", "compositor");
+  sink = gst_element_factory_make ("fakesink", "sink");
+  gst_bin_add_many (GST_BIN (bin), src1, src2, src3, filter1, filter2, filter3,
+      compositor, sink, NULL);
+
+  /* configure capsfilters */
+  caps = gst_caps_from_string ("video/x-raw,width=800,height=400");
+  g_object_set (filter1, "caps", caps, NULL);
+  gst_caps_unref (caps);
+  caps = gst_caps_from_string ("video/x-raw,width=400,height=200");
+  g_object_set (filter2, "caps", caps, NULL);
+  gst_caps_unref (caps);
+  caps = gst_caps_from_string ("video/x-raw,width=200,height=50");
+  g_object_set (filter3, "caps", caps, NULL);
+  gst_caps_unref (caps);
+
+  res = gst_element_link_many (src1, filter1, compositor, NULL);
+  fail_unless (res == TRUE, NULL);
+  res = gst_element_link_many (src2, filter2, compositor, NULL);
+  fail_unless (res == TRUE, NULL);
+  res = gst_element_link_many (src3, filter3, compositor, NULL);
+  fail_unless (res == TRUE, NULL);
+  res = gst_element_link (compositor, sink);
+  fail_unless (res == TRUE, NULL);
+
+  srcpad = gst_element_get_static_pad (compositor, "src");
+  gst_object_unref (srcpad);
+
+  /* configure pads and add probes */
+  srcpad = gst_element_get_static_pad (filter1, "src");
+  sinkpad = gst_pad_get_peer (srcpad);
+  g_object_set (sinkpad,
+      "width", 400, "height", 300, "xpos", 200, "ypos", 100, NULL);
+  probe_events[0].received = FALSE;
+  gst_pad_add_probe (srcpad, GST_PAD_PROBE_TYPE_EVENT_UPSTREAM,
+      probe_nav_event, (gpointer) probe_events, NULL);
+  gst_object_unref (srcpad);
+  gst_object_unref (sinkpad);
+
+  srcpad = gst_element_get_static_pad (filter2, "src");
+  sinkpad = gst_pad_get_peer (srcpad);
+  g_object_set (sinkpad,
+      "width", 400, "height", 200, "xpos", 20, "ypos", 0, NULL);
+  probe_events[1].received = FALSE;
+  gst_pad_add_probe (srcpad, GST_PAD_PROBE_TYPE_EVENT_UPSTREAM,
+      probe_nav_event, (gpointer) (probe_events + 1), NULL);
+  gst_object_unref (srcpad);
+  gst_object_unref (sinkpad);
+
+  srcpad = gst_element_get_static_pad (filter3, "src");
+  sinkpad = gst_pad_get_peer (srcpad);
+  g_object_set (sinkpad,
+      "width", 200, "height", 50, "xpos", 0, "ypos", 0, NULL);
+  probe_events[2].received = FALSE;
+  gst_pad_add_probe (srcpad, GST_PAD_PROBE_TYPE_EVENT_UPSTREAM,
+      probe_nav_event, (gpointer) (probe_events + 2), NULL);
+  gst_object_unref (srcpad);
+  gst_object_unref (sinkpad);
+
+  event =
+      gst_event_new_navigation (gst_structure_new
+      ("application/x-gst-navigation", "event", G_TYPE_STRING, "mouse-move",
+          "button", G_TYPE_INT, 0, "pointer_x", G_TYPE_DOUBLE, 350.0,
+          "pointer_y", G_TYPE_DOUBLE, 100.0, NULL));
+
+  GST_INFO ("starting test");
+
+  /* prepare playing */
+  state_res = gst_element_set_state (bin, GST_STATE_PAUSED);
+  ck_assert_int_ne (state_res, GST_STATE_CHANGE_FAILURE);
+
+  /* wait for completion */
+  state_res = gst_element_get_state (bin, NULL, NULL, GST_CLOCK_TIME_NONE);
+  ck_assert_int_ne (state_res, GST_STATE_CHANGE_FAILURE);
+
+  /* send event and validate */
+  res = gst_element_send_event (sink, event);
+  fail_unless (res == TRUE, NULL);
+
+  /* check received events */
+  ck_assert_msg (probe_events[0].received);
+  ck_assert_msg (probe_events[1].received);
+  ck_assert_msg (!probe_events[2].received);
+
+  ck_assert_int_eq ((gint) probe_events[0].x_pos, 300);
+  ck_assert_int_eq ((gint) probe_events[0].y_pos, 0);
+  ck_assert_int_eq ((gint) probe_events[1].x_pos, 330);
+  ck_assert_int_eq ((gint) probe_events[1].y_pos, 100);
+
+  state_res = gst_element_set_state (bin, GST_STATE_NULL);
+  ck_assert_int_ne (state_res, GST_STATE_CHANGE_FAILURE);
+
+  gst_object_unref (bin);
+}
+
+GST_END_TEST;
+
 static GstBuffer *
 create_video_buffer (GstCaps * caps, gint ts_in_seconds)
 {
@@ -2386,6 +2525,7 @@ compositor_suite (void)
   suite_add_tcase (s, tc_chain);
   tcase_add_test (tc_chain, test_caps);
   tcase_add_test (tc_chain, test_event);
+  tcase_add_test (tc_chain, test_navigation_events);
   tcase_add_test (tc_chain, test_caps_query);
   tcase_add_test (tc_chain, test_caps_query_interlaced);
   tcase_add_test (tc_chain, test_late_caps_query);

subprojects/gstreamer/libs/gst/base/gstaggregator.c

@@ -2412,7 +2412,7 @@ gst_aggregator_default_src_event (GstAggregator * self, GstEvent * event)
       /* _do_seek() unrefs the event. */
       return gst_aggregator_do_seek (self, event);
     case GST_EVENT_NAVIGATION:
-      /* navigation is rather pointless. */
+      /* specific handling has to be implemented in subclasses */
       gst_event_unref (event);
       return FALSE;
     case GST_EVENT_RECONFIGURE: