UI: Add transition management APIs

UI/api-interface.cpp

@@ -110,6 +110,20 @@ struct OBSStudioAPI : obs_frontend_callbacks {
 		}
 	}
 
+	void obs_frontend_add_transition(obs_source_t *transition) override
+	{
+		QMetaObject::invokeMethod(main, "AddTransitionInstance",
+					  Q_ARG(OBSSource,
+						OBSSource(transition)));
+	}
+
+	void obs_frontend_remove_transition(obs_source_t *transition) override
+	{
+		QMetaObject::invokeMethod(main, "RemoveTransitionInstance",
+					  Q_ARG(OBSSource,
+						OBSSource(transition)));
+	}
+
 	void obs_frontend_get_transitions(
 		struct obs_frontend_source_list *sources) override
 	{

UI/obs-frontend-api/obs-frontend-api.cpp

@@ -112,6 +112,18 @@ void obs_frontend_set_current_scene(obs_source_t *scene)
 		c->obs_frontend_set_current_scene(scene);
 }
 
+void obs_frontend_add_transition(obs_source_t *transition)
+{
+	if (callbacks_valid())
+		c->obs_frontend_add_transition(transition);
+}
+
+void obs_frontend_remove_transition(obs_source_t *transition)
+{
+	if (callbacks_valid())
+		c->obs_frontend_remove_transition(transition);
+}
+
 void obs_frontend_get_transitions(struct obs_frontend_source_list *sources)
 {
 	if (callbacks_valid())

UI/obs-frontend-api/obs-frontend-api.h

@@ -107,6 +107,8 @@ EXPORT void obs_frontend_get_scenes(struct obs_frontend_source_list *sources);
 EXPORT obs_source_t *obs_frontend_get_current_scene(void);
 EXPORT void obs_frontend_set_current_scene(obs_source_t *scene);
 
+EXPORT void obs_frontend_add_transition(obs_source_t *transition);
+EXPORT void obs_frontend_remove_transition(obs_source_t *transition);
 EXPORT void
 obs_frontend_get_transitions(struct obs_frontend_source_list *sources);
 EXPORT obs_source_t *obs_frontend_get_current_transition(void);

UI/obs-frontend-api/obs-frontend-internal.hpp

@@ -16,6 +16,9 @@ struct obs_frontend_callbacks {
 	virtual obs_source_t *obs_frontend_get_current_scene(void) = 0;
 	virtual void obs_frontend_set_current_scene(obs_source_t *scene) = 0;
 
+	virtual void obs_frontend_add_transition(obs_source_t *transition) = 0;
+	virtual void
+	obs_frontend_remove_transition(obs_source_t *transition) = 0;
 	virtual void obs_frontend_get_transitions(
 		struct obs_frontend_source_list *sources) = 0;
 	virtual obs_source_t *obs_frontend_get_current_transition(void) = 0;

UI/window-basic-main-transitions.cpp

@@ -142,25 +142,50 @@ void OBSBasic::RemoveQuickTransitionHotkey(QuickTransition *qt)
 	obs_hotkey_unregister(qt->hotkey);
 }
 
-void OBSBasic::InitTransition(obs_source_t *transition)
+static void initTransitionOnStop(void *data, calldata_t *)
 {
-	auto onTransitionStop = [](void *data, calldata_t *) {
-		OBSBasic *window = (OBSBasic *)data;
-		QMetaObject::invokeMethod(window, "TransitionStopped",
-					  Qt::QueuedConnection);
-	};
+	OBSBasic *window = (OBSBasic *)data;
+	QMetaObject::invokeMethod(window, "TransitionStopped",
+				  Qt::QueuedConnection);
+}
 
-	auto onTransitionFullStop = [](void *data, calldata_t *) {
-		OBSBasic *window = (OBSBasic *)data;
-		QMetaObject::invokeMethod(window, "TransitionFullyStopped",
-					  Qt::QueuedConnection);
-	};
+static void initTransitionOnFullStop(void *data, calldata_t *)
+{
+	OBSBasic *window = (OBSBasic *)data;
+	QMetaObject::invokeMethod(window, "TransitionFullyStopped",
+				  Qt::QueuedConnection);
+}
 
+static void initTransitionOnRename(void *data, calldata_t *calldata)
+{
+	OBSBasic *window = (OBSBasic *)data;
+	OBSSource source((obs_source_t *)calldata_ptr(calldata, "source"));
+
+	QMetaObject::invokeMethod(window, "TransitionWasRenamed",
+				  Qt::QueuedConnection,
+				  Q_ARG(OBSSource, source));
+}
+
+void OBSBasic::InitTransition(obs_source_t *transition)
+{
 	signal_handler_t *handler = obs_source_get_signal_handler(transition);
 	signal_handler_connect(handler, "transition_video_stop",
-			       onTransitionStop, this);
-	signal_handler_connect(handler, "transition_stop", onTransitionFullStop,
-			       this);
+			       initTransitionOnStop, this);
+	signal_handler_connect(handler, "transition_stop",
+			       initTransitionOnFullStop, this);
+	signal_handler_connect(handler, "rename", initTransitionOnRename, this);
+}
+
+void OBSBasic::DeinitTransition(obs_source_t *transition)
+{
+	signal_handler_t *handler = obs_source_get_signal_handler(transition);
+
+	signal_handler_disconnect(handler, "transition_video_stop",
+				  initTransitionOnStop, this);
+	signal_handler_disconnect(handler, "transition_stop",
+				  initTransitionOnFullStop, this);
+	signal_handler_disconnect(handler, "rename", initTransitionOnRename,
+				  this);
 }
 
 static inline OBSSource GetTransitionComboItem(QComboBox *combo, int idx)
@@ -256,6 +281,38 @@ void OBSBasic::TransitionToScene(OBSScene scene, bool force)
 	TransitionToScene(source, force);
 }
 
+void OBSBasic::TransitionWasRenamed(OBSSource transition)
+{
+	int idx = ui->transitions->findData(QVariant::fromValue(transition));
+	if (idx == -1) {
+		return;
+	}
+
+	string name = obs_source_get_name(transition);
+
+	obs_source_t *source = FindTransition(name.c_str());
+	if (source != transition) {
+		int copy = 1;
+		string updatedName = name;
+		while (source) {
+			updatedName = name + " " + to_string(++copy);
+			source = FindTransition(updatedName.c_str());
+		}
+		if (copy > 1) {
+			name = std::move(updatedName);
+			obs_source_set_name(transition, name.c_str());
+		}
+	}
+
+	ui->transitions->setItemText(idx, QT_UTF8(name.c_str()));
+
+	if (api)
+		api->on_event(OBS_FRONTEND_EVENT_TRANSITION_LIST_CHANGED);
+
+	ClearQuickTransitionWidgets();
+	RefreshQuickTransitions();
+}
+
 void OBSBasic::TransitionStopped()
 {
 	if (swapScenesMode) {
@@ -427,6 +484,69 @@ static inline void SetComboTransition(QComboBox *combo, obs_source_t *tr)
 	}
 }
 
+void OBSBasic::AddTransitionInstance(OBSSource transition)
+{
+	int idx = ui->transitions->findData(QVariant::fromValue(transition));
+	if (idx != -1)
+		return;
+
+	string name = obs_source_get_name(transition);
+
+	obs_source_t *source = FindTransition(name.c_str());
+	int copy = 1;
+	string updatedName = name;
+	while (source) {
+		updatedName = name + " " + to_string(++copy);
+		source = FindTransition(updatedName.c_str());
+	}
+	if (copy > 1) {
+		name = std::move(updatedName);
+		obs_source_set_name(transition, name.c_str());
+	}
+
+	InitTransition(transition);
+
+	ui->transitions->addItem(QT_UTF8(name.c_str()),
+				 QVariant::fromValue(transition));
+
+	if (api)
+		api->on_event(OBS_FRONTEND_EVENT_TRANSITION_LIST_CHANGED);
+
+	ClearQuickTransitionWidgets();
+	RefreshQuickTransitions();
+}
+
+void OBSBasic::RemoveTransitionInstance(OBSSource transition)
+{
+	if (!transition || !obs_source_configurable(transition))
+		return;
+
+	int idx = ui->transitions->findData(QVariant::fromValue(transition));
+	if (idx == -1)
+		return;
+
+	DeinitTransition(transition);
+
+	for (size_t i = quickTransitions.size(); i > 0; i--) {
+		QuickTransition &qt = quickTransitions[i - 1];
+		if (qt.source == transition) {
+			if (qt.button)
+				qt.button->deleteLater();
+			RemoveQuickTransitionHotkey(&qt);
+			quickTransitions.erase(quickTransitions.begin() + i -
+					       1);
+		}
+	}
+
+	ui->transitions->removeItem(idx);
+
+	if (api)
+		api->on_event(OBS_FRONTEND_EVENT_TRANSITION_LIST_CHANGED);
+
+	ClearQuickTransitionWidgets();
+	RefreshQuickTransitions();
+}
+
 void OBSBasic::SetTransition(OBSSource transition)
 {
 	OBSSourceAutoRelease oldTransition = obs_get_output_source(0);
@@ -544,32 +664,8 @@ void OBSBasic::on_transitionAdd_clicked()
 void OBSBasic::on_transitionRemove_clicked()
 {
 	OBSSource tr = GetCurrentTransition();
-
-	if (!tr || !obs_source_configurable(tr) || !QueryRemoveSource(tr))
-		return;
-
-	int idx = ui->transitions->findData(QVariant::fromValue<OBSSource>(tr));
-	if (idx == -1)
-		return;
-
-	for (size_t i = quickTransitions.size(); i > 0; i--) {
-		QuickTransition &qt = quickTransitions[i - 1];
-		if (qt.source == tr) {
-			if (qt.button)
-				qt.button->deleteLater();
-			RemoveQuickTransitionHotkey(&qt);
-			quickTransitions.erase(quickTransitions.begin() + i -
-					       1);
-		}
-	}
-
-	ui->transitions->removeItem(idx);
-
-	if (api)
-		api->on_event(OBS_FRONTEND_EVENT_TRANSITION_LIST_CHANGED);
-
-	ClearQuickTransitionWidgets();
-	RefreshQuickTransitions();
+	if (QueryRemoveSource(tr))
+		RemoveTransitionInstance(tr);
 }
 
 void OBSBasic::RenameTransition(OBSSource transition)

UI/window-basic-main.hpp

@@ -461,6 +461,7 @@ class OBSBasic : public OBSMainWindow {
 
 	void InitDefaultTransitions();
 	void InitTransition(obs_source_t *transition);
+	void DeinitTransition(obs_source_t *transition);
 	obs_source_t *FindTransition(const char *name);
 	OBSSource GetCurrentTransition();
 	obs_data_array_t *SaveTransitions();
@@ -719,6 +720,8 @@ public slots:
 	void SaveProjectDeferred();
 	void SaveProject();
 
+	void AddTransitionInstance(OBSSource transition);
+	void RemoveTransitionInstance(OBSSource transition);
 	void SetTransition(OBSSource transition);
 	void OverrideTransition(OBSSource transition);
 	void TransitionToScene(OBSScene scene, bool force = false);
@@ -767,6 +770,7 @@ private slots:
 
 	void AddTransition(const char *id);
 	void RenameTransition(OBSSource transition);
+	void TransitionWasRenamed(OBSSource transition);
 	void TransitionClicked();
 	void TransitionStopped();
 	void TransitionFullyStopped();

docs/sphinx/reference-frontend-api.rst

@@ -309,6 +309,24 @@ Functions
 
 ---------------------------------------
 
+.. function:: void obs_frontend_add_transition(obs_source_t *transition)
+
+   :param transition: The transition to add to the frontend's transition list.
+                      This source should be created with
+                      :c:func:`obs_source_create_private()` to ensure behavior is
+                      consistent with the transitions created by a user.
+                      The transition can be safely renamed with
+                      :c:func:`obs_source_set_name()`
+
+---------------------------------------
+
+.. function:: void obs_frontend_remove_transition(obs_source_t *transition)
+
+   :param transition: The transition that should be removed from the frontend's
+                      transition list
+
+---------------------------------------
+
 .. function:: void obs_frontend_get_transitions(struct obs_frontend_source_list *sources)
 
    :param sources: Pointer to a :c:type:`obs_frontend_source_list`