feat(events): add "TransitionEnd" and "TransitionVideoEnd" events

Adds events for `TransitionEnd` and `TransitionVideoEnd`.

`TransitionVideoEnd` is specific to Stinger transitions. It is fired when their video has actually completed playback. This is important, because `TransitionEnd` is fired at the cut point of the Stinger, which is nice to have but isn't always what the user might want.

This builds on #409, and should be merged after it.

src/Utils.cpp

@@ -413,6 +413,30 @@ bool Utils::SetTransitionByName(QString transitionName) {
 	}
 }
 
+obs_data_t* Utils::GetTransitionData(obs_source_t* transition) {
+	int duration = Utils::GetTransitionDuration(transition);
+	if (duration < 0) {
+		blog(LOG_WARNING, "GetTransitionData: duration is negative !");
+	}
+
+	obs_data_t* transitionData = obs_data_create();
+	obs_data_set_string(transitionData, "name", obs_source_get_name(transition));
+	obs_data_set_string(transitionData, "type", obs_source_get_id(transition));
+	obs_data_set_int(transitionData, "duration", duration);
+
+	OBSSourceAutoRelease sourceScene = obs_transition_get_source(transition, OBS_TRANSITION_SOURCE_A);
+	if (sourceScene) {
+		obs_data_set_string(transitionData, "from-scene", obs_source_get_name(sourceScene));
+	}
+
+	OBSSourceAutoRelease destinationScene = obs_transition_get_active_source(transition);
+	if (destinationScene) {
+		obs_data_set_string(transitionData, "to-scene", obs_source_get_name(destinationScene));
+	}
+
+	return transitionData;
+}
+
 QString Utils::OBSVersionString() {
 	uint32_t version = obs_get_version();
 

src/Utils.h

@@ -60,6 +60,7 @@ namespace Utils {
 	int GetTransitionDuration(obs_source_t* transition);
 	obs_source_t* GetTransitionFromName(QString transitionName);
 	bool SetTransitionByName(QString transitionName);
+	obs_data_t* GetTransitionData(obs_source_t* transition);
 
 	QString OBSVersionString();
 

src/WSEvents.cpp

@@ -122,7 +122,7 @@ void WSEvents::FrontendEventHandler(enum obs_frontend_event event, void* private
 
 	switch (event) {
 		case OBS_FRONTEND_EVENT_FINISHED_LOADING:
-			owner->hookTransitionBeginEvent();
+			owner->hookTransitionPlaybackEvents();
 			break;
 	
 		case OBS_FRONTEND_EVENT_SCENE_CHANGED:
@@ -134,7 +134,7 @@ void WSEvents::FrontendEventHandler(enum obs_frontend_event event, void* private
 			break;
 
 		case OBS_FRONTEND_EVENT_SCENE_COLLECTION_CHANGED:
-			owner->hookTransitionBeginEvent();
+			owner->hookTransitionPlaybackEvents();
 			owner->OnSceneCollectionChange();
 			break;
 
@@ -147,7 +147,7 @@ void WSEvents::FrontendEventHandler(enum obs_frontend_event event, void* private
 			break;
 
 		case OBS_FRONTEND_EVENT_TRANSITION_LIST_CHANGED:
-			owner->hookTransitionBeginEvent();
+			owner->hookTransitionPlaybackEvents();
 			owner->OnTransitionListChange();
 			break;
 
@@ -231,7 +231,7 @@ void WSEvents::FrontendEventHandler(enum obs_frontend_event event, void* private
 			break;
 
 		case OBS_FRONTEND_EVENT_EXIT:
-			owner->unhookTransitionBeginEvent();
+			owner->unhookTransitionPlaybackEvents();
 			owner->OnExit();
 			break;
 	}
@@ -309,6 +309,8 @@ void WSEvents::disconnectSourceSignals(obs_source_t* source) {
 	signal_handler_disconnect(sh, "item_deselect", OnSceneItemDeselected, this);
 
 	signal_handler_disconnect(sh, "transition_start", OnTransitionBegin, this);
+	signal_handler_disconnect(sh, "transition_stop", OnTransitionEnd, this);
+	signal_handler_disconnect(sh, "transition_video_stop", OnTransitionVideoEnd, this);
 }
 
 void WSEvents::connectFilterSignals(obs_source_t* filter) {
@@ -331,7 +333,7 @@ void WSEvents::disconnectFilterSignals(obs_source_t* filter) {
 	signal_handler_disconnect(sh, "enable", OnSourceFilterVisibilityChanged, this);
 }
 
-void WSEvents::hookTransitionBeginEvent() {
+void WSEvents::hookTransitionPlaybackEvents() {
 	obs_frontend_source_list transitions = {};
 	obs_frontend_get_transitions(&transitions);
 
@@ -340,12 +342,16 @@ void WSEvents::hookTransitionBeginEvent() {
 		signal_handler_t* sh = obs_source_get_signal_handler(transition);
 		signal_handler_disconnect(sh, "transition_start", OnTransitionBegin, this);
 		signal_handler_connect(sh, "transition_start", OnTransitionBegin, this);
+		signal_handler_disconnect(sh, "transition_stop", OnTransitionEnd, this);
+		signal_handler_connect(sh, "transition_stop", OnTransitionEnd, this);
+		signal_handler_disconnect(sh, "transition_video_stop", OnTransitionVideoEnd, this);
+		signal_handler_connect(sh, "transition_video_stop", OnTransitionVideoEnd, this);
 	}
 
 	obs_frontend_source_list_free(&transitions);
 }
 
-void WSEvents::unhookTransitionBeginEvent() {
+void WSEvents::unhookTransitionPlaybackEvents() {
 	obs_frontend_source_list transitions = {};
 	obs_frontend_get_transitions(&transitions);
 
@@ -353,6 +359,8 @@ void WSEvents::unhookTransitionBeginEvent() {
 		obs_source_t* transition = transitions.sources.array[i];
 		signal_handler_t* sh = obs_source_get_signal_handler(transition);
 		signal_handler_disconnect(sh, "transition_start", OnTransitionBegin, this);
+		signal_handler_disconnect(sh, "transition_stop", OnTransitionEnd, this);
+		signal_handler_disconnect(sh, "transition_video_stop", OnTransitionVideoEnd, this);
 	}
 
 	obs_frontend_source_list_free(&transitions);
@@ -895,29 +903,62 @@ void WSEvents::OnTransitionBegin(void* param, calldata_t* data) {
 		return;
 	}
 
-	int duration = Utils::GetTransitionDuration(transition);
-	if (duration < 0) {
-		blog(LOG_WARNING, "OnTransitionBegin: duration is negative !");
-	}
-
-	OBSDataAutoRelease fields = obs_data_create();
-	obs_data_set_string(fields, "name", obs_source_get_name(transition));
-	obs_data_set_string(fields, "type", obs_source_get_id(transition));
-	obs_data_set_int(fields, "duration", duration);
-
-	OBSSourceAutoRelease sourceScene = obs_transition_get_source(transition, OBS_TRANSITION_SOURCE_A);
-	if (sourceScene) {
-		obs_data_set_string(fields, "from-scene", obs_source_get_name(sourceScene));
-	}
-
-	OBSSourceAutoRelease destinationScene = obs_transition_get_active_source(transition);
-	if (destinationScene) {
-		obs_data_set_string(fields, "to-scene", obs_source_get_name(destinationScene));
-	}
-
+	OBSDataAutoRelease fields = Utils::GetTransitionData(transition);
 	instance->broadcastUpdate("TransitionBegin", fields);
 }
 
+/**
+* A transition (other than "cut") has ended.
+*
+* @return {String} `name` Transition name.
+* @return {String} `type` Transition type.
+* @return {int} `duration` Transition duration (in milliseconds).
+* @return {String} `from-scene` Source scene of the transition
+* @return {String} `to-scene` Destination scene of the transition
+*
+* @api events
+* @name TransitionEnd
+* @category transitions
+* @since 4.8.0
+*/
+void WSEvents::OnTransitionEnd(void* param, calldata_t* data) {
+	auto instance = reinterpret_cast<WSEvents*>(param);
+
+	OBSSource transition = calldata_get_pointer<obs_source_t>(data, "source");
+	if (!transition) {
+		return;
+	}
+
+	OBSDataAutoRelease fields = Utils::GetTransitionData(transition);
+	instance->broadcastUpdate("TransitionEnd", fields);
+}
+
+/**
+* A stinger transition has finished playing its video.
+*
+* @return {String} `name` Transition name.
+* @return {String} `type` Transition type.
+* @return {int} `duration` Transition duration (in milliseconds).
+* @return {String} `from-scene` Source scene of the transition
+* @return {String} `to-scene` Destination scene of the transition
+*
+* @api events
+* @name TransitionVideoEnd
+* @category transitions
+* @since 4.8.0
+*/
+void WSEvents::OnTransitionVideoEnd(void* param, calldata_t* data) {
+	auto instance = reinterpret_cast<WSEvents*>(param);
+
+	OBSSource transition = calldata_get_pointer<obs_source_t>(data, "source");
+	if (!transition) {
+		return;
+	}
+
+	OBSDataAutoRelease fields = Utils::GetTransitionData(transition);
+	instance->broadcastUpdate("TransitionVideoEnd", fields);
+}
+
 /**
  * A source has been created. A source can be an input, a scene or a transition.
  *

src/WSEvents.h

@@ -43,8 +43,8 @@ public:
 	void connectFilterSignals(obs_source_t* filter);
 	void disconnectFilterSignals(obs_source_t* filter);
 
-	void hookTransitionBeginEvent();
-	void unhookTransitionBeginEvent();
+	void hookTransitionPlaybackEvents();
+	void unhookTransitionPlaybackEvents();
 
 	uint64_t getStreamingTime();
 	uint64_t getRecordingTime();
@@ -116,6 +116,8 @@ private:
 		enum obs_frontend_event event, void* privateData);
 
 	static void OnTransitionBegin(void* param, calldata_t* data);
+	static void OnTransitionEnd(void* param, calldata_t* data);
+	static void OnTransitionVideoEnd(void* param, calldata_t* data);
 
 	static void OnSourceCreate(void* param, calldata_t* data);
 	static void OnSourceDestroy(void* param, calldata_t* data);