Delay setting of default scene transitions (#116)

src/advanced-scene-switcher.cpp

@@ -428,9 +428,6 @@ void SwitcherData::Thread()
 		OBSWeakSource scene;
 		OBSWeakSource transition;
 
-		bool defTransitionMatch = false;
-		OBSWeakSource defTransition;
-
 		endTime = std::chrono::high_resolution_clock::now();
 
 		auto runTime =
@@ -466,8 +463,6 @@ void SwitcherData::Thread()
 			continue;
 		}
 
-		checkDefaultSceneTransitions(defTransitionMatch, defTransition);
-
 		for (int switchFuncName : functionNamesByPriority) {
 			switch (switchFuncName) {
 			case read_file_func:
@@ -544,10 +539,6 @@ void SwitcherData::Thread()
 		// leading to a deadlock, so we have to unlock()
 		lock.unlock();
 
-		if (!match && defTransitionMatch) {
-			setCurrentDefTransition(defTransition);
-		}
-
 		if (match) {
 			switchScene(scene, transition,
 				    tansitionOverrideOverride);
@@ -658,12 +649,8 @@ void handleSceneChange(SwitcherData *s)
 		s->previousSceneHelper = ws;
 	}
 
-	switcher->checkTriggers();
-}
-
-void handleTransitionStop(SwitcherData *s)
-{
-	s->checkedDefTransition = false;
+	s->checkTriggers();
+	s->checkDefaultSceneTransitions();
 }
 
 void setLiveTime(SwitcherData *s)
@@ -702,9 +689,6 @@ static void OBSEvent(enum obs_frontend_event event, void *switcher)
 	case OBS_FRONTEND_EVENT_SCENE_CHANGED:
 		handleSceneChange((SwitcherData *)switcher);
 		break;
-	case OBS_FRONTEND_EVENT_TRANSITION_STOPPED:
-		handleTransitionStop((SwitcherData *)switcher);
-		break;
 	case OBS_FRONTEND_EVENT_RECORDING_STARTED:
 		setLiveTime((SwitcherData *)switcher);
 		checkAutoStartRecording((SwitcherData *)switcher);

src/headers/switch-transitions.hpp

@@ -20,6 +20,8 @@ struct DefaultSceneTransition : SceneSwitcherEntry {
 	static bool pause;
 
 	const char *getType() { return "def_transition"; }
+	bool checkMatch(OBSWeakSource currentScene);
+	void setTransition();
 
 	inline DefaultSceneTransition(){};
 	inline DefaultSceneTransition(OBSWeakSource scene_,

src/headers/switcher-data-structs.hpp

@@ -100,7 +100,6 @@ struct SwitcherData {
 
 	std::deque<SceneTransition> sceneTransitions;
 	std::deque<DefaultSceneTransition> defaultSceneTransitions;
-	bool checkedDefTransition = false;
 
 	std::deque<MediaSwitch> mediaSwitches;
 
@@ -164,9 +163,7 @@ struct SwitcherData {
 	void writeSceneInfoToFile();
 	void writeToStatusFile(QString status);
 	bool checkPause();
-	void checkDefaultSceneTransitions(bool &match,
-					  OBSWeakSource &transition);
-	void setCurrentDefTransition(OBSWeakSource &transition);
+	void checkDefaultSceneTransitions();
 	void checkSceneSequence(bool &match, OBSWeakSource &scene,
 				OBSWeakSource &transition, int &linger);
 	void checkIdleSwitch(bool &match, OBSWeakSource &scene,

src/switch-transitions.cpp

@@ -1,3 +1,5 @@
+#include <thread>
+
 #include "headers/advanced-scene-switcher.hpp"
 #include "headers/utility.hpp"
 
@@ -148,42 +150,28 @@ void AdvSceneSwitcher::on_defaultTransitionsDown_clicked()
 		  switcher->defaultSceneTransitions[index + 1]);
 }
 
-void SwitcherData::checkDefaultSceneTransitions(bool &match,
-						OBSWeakSource &transition)
+void SwitcherData::checkDefaultSceneTransitions()
 {
-	if (checkedDefTransition || DefaultSceneTransition::pause) {
+	if (DefaultSceneTransition::pause || stop) {
 		return;
 	}
 
-	obs_source_t *currentSource = obs_frontend_get_current_scene();
-	obs_weak_source_t *ws = obs_source_get_weak_source(currentSource);
-
-	for (DefaultSceneTransition &s : defaultSceneTransitions) {
-		if (s.scene == ws) {
-			if (!s.initialized()) {
-				continue;
-			}
-
-			match = true;
-			transition = s.transition;
+	obs_source_t *currentSceneSource = obs_frontend_get_current_scene();
+	obs_weak_source_t *currentScene =
+		obs_source_get_weak_source(currentSceneSource);
 
+	for (auto &t : defaultSceneTransitions) {
+		if (t.checkMatch(currentScene)) {
 			if (verbose) {
-				s.logMatch();
+				t.logMatch();
 			}
+			t.setTransition();
 			break;
 		}
 	}
-	obs_source_release(currentSource);
-	obs_weak_source_release(ws);
 
-	checkedDefTransition = true;
-}
-
-void SwitcherData::setCurrentDefTransition(OBSWeakSource &transition)
-{
-	obs_source_t *transitionSource = obs_weak_source_get_source(transition);
-	obs_frontend_set_current_transition(transitionSource);
-	obs_source_release(transitionSource);
+	obs_weak_source_release(currentScene);
+	obs_source_release(currentSceneSource);
 }
 
 void AdvSceneSwitcher::on_transitionOverridecheckBox_stateChanged(int state)
@@ -533,3 +521,37 @@ void DefTransitionSwitchWidget::swapSwitchData(DefTransitionSwitchWidget *s1,
 	s1->setSwitchData(s2->getSwitchData());
 	s2->setSwitchData(t);
 }
+
+bool DefaultSceneTransition::checkMatch(OBSWeakSource currentScene)
+{
+	return scene == currentScene;
+}
+
+void setTransitionDelayed(OBSWeakSource transition)
+{
+	// A hardcoded delay of 50 ms before switching transition type is
+	// necessary due to OBS_FRONTEND_EVENT_SCENE_CHANGED seemingly firing a
+	// bit too early and thus leading to canceled transitions.
+	//
+	// The same is to be the case for OBS_FRONTEND_EVENT_TRANSITION_STOPPED.
+	//
+	// 50 ms was chosen as it seems to avoid the problem mentioned above and
+	// becuase that is the minimum value which can be chosen for the scene
+	// switcher's check interval.
+	// Thus it can be made sure that the delayed setting of the transition
+	// does not interfere with any new scene changes triggered by the scene
+	// switcher
+
+	std::this_thread::sleep_for(std::chrono::milliseconds(50));
+
+	obs_source_t *transitionSource = obs_weak_source_get_source(transition);
+	obs_frontend_set_current_transition(transitionSource);
+	obs_source_release(transitionSource);
+}
+
+void DefaultSceneTransition::setTransition()
+{
+	std::thread t;
+	t = std::thread(setTransitionDelayed, transition);
+	t.detach();
+}