Handle MIDI device disconnect and reconnect

The Create() and Copy() functions were not correctly implemented and
returned a nullptr

CMakeLists.txt

@@ -151,6 +151,8 @@ target_sources(
           lib/utils/backup.hpp
           lib/utils/curl-helper.cpp
           lib/utils/curl-helper.hpp
+          lib/utils/double-slider.cpp
+          lib/utils/double-slider.hpp
           lib/utils/duration-control.cpp
           lib/utils/duration-control.hpp
           lib/utils/duration.cpp

lib/legacy/switch-audio.cpp

@@ -437,10 +437,8 @@ AudioSwitchWidget::AudioSwitchWidget(QWidget *parent, AudioSwitch *s)
 	audioVolumeThreshold->setMaximum(100);
 	audioVolumeThreshold->setMinimum(0);
 
-	QWidget::connect(volMeter->GetSlider(), SIGNAL(valueChanged(int)),
-			 audioVolumeThreshold, SLOT(setValue(int)));
-	QWidget::connect(audioVolumeThreshold, SIGNAL(valueChanged(int)),
-			 volMeter->GetSlider(), SLOT(setValue(int)));
+	QWidget::connect(volMeter->GetSlider(), &DoubleSlider::DoubleValChanged,
+			 [=](double) { SyncSliderAndValueSelection(true); });
 	QWidget::connect(audioVolumeThreshold, SIGNAL(valueChanged(int)), this,
 			 SLOT(VolumeThresholdChanged(int)));
 	QWidget::connect(condition, SIGNAL(currentIndexChanged(int)), this,
@@ -487,6 +485,7 @@ AudioSwitchWidget::AudioSwitchWidget(QWidget *parent, AudioSwitch *s)
 	switchData = s;
 
 	loading = false;
+	SyncSliderAndValueSelection(false);
 }
 
 AudioSwitch *AudioSwitchWidget::getSwitchData()
@@ -509,6 +508,21 @@ void AudioSwitchWidget::swapSwitchData(AudioSwitchWidget *s1,
 	s2->setSwitchData(t);
 }
 
+void AudioSwitchWidget::SyncSliderAndValueSelection(bool sliderMoved)
+{
+	if (loading || !switchData) {
+		return;
+	}
+
+	if (sliderMoved) {
+		auto sliderPosition = volMeter->GetSlider()->DoubleValue();
+		audioVolumeThreshold->setValue(sliderPosition);
+	} else {
+		volMeter->GetSlider()->SetDoubleVal(
+			switchData->volumeThreshold);
+	}
+}
+
 void AudioSwitchWidget::UpdateVolmeterSource()
 {
 	delete volMeter;
@@ -520,10 +534,8 @@ void AudioSwitchWidget::UpdateVolmeterSource()
 	QLayout *layout = this->layout();
 	layout->addWidget(volMeter);
 
-	QWidget::connect(volMeter->GetSlider(), SIGNAL(valueChanged(int)),
-			 audioVolumeThreshold, SLOT(setValue(int)));
-	QWidget::connect(audioVolumeThreshold, SIGNAL(valueChanged(int)),
-			 volMeter->GetSlider(), SLOT(setValue(int)));
+	QWidget::connect(volMeter->GetSlider(), &DoubleSlider::DoubleValChanged,
+			 [=](double) { SyncSliderAndValueSelection(true); });
 
 	// Slider will default to 0 so set it manually once
 	volMeter->GetSlider()->setValue(switchData->volumeThreshold);
@@ -547,8 +559,11 @@ void AudioSwitchWidget::VolumeThresholdChanged(int vol)
 		return;
 	}
 
-	std::lock_guard<std::mutex> lock(switcher->m);
-	switchData->volumeThreshold = vol;
+	{
+		std::lock_guard<std::mutex> lock(switcher->m);
+		switchData->volumeThreshold = vol;
+	}
+	SyncSliderAndValueSelection(false);
 }
 
 void AudioSwitchWidget::ConditionChanged(int cond)

lib/legacy/switch-audio.hpp

@@ -79,6 +79,7 @@ private slots:
 	void ConditionChanged(int cond);
 	void DurationChanged(const Duration &);
 	void IgnoreInactiveChanged(int state);
+	void SyncSliderAndValueSelection(bool sliderMoved);
 
 private:
 	QComboBox *audioSources;

lib/macro/macro-tab.cpp

@@ -1,4 +1,5 @@
 #include "advanced-scene-switcher.hpp"
+#include "action-queue.hpp"
 #include "macro-action-edit.hpp"
 #include "macro-condition-edit.hpp"
 #include "macro-export-import-dialog.hpp"
@@ -13,6 +14,7 @@
 #include "utility.hpp"
 #include "version.h"
 
+#include <obs-frontend-api.h>
 #include <QColor>
 #include <QGraphicsOpacityEffect>
 #include <QMenu>
@@ -247,6 +249,7 @@ void AdvSceneSwitcher::ExportMacros()
 	}
 	obs_data_set_array(data, "macros", macroArray);
 	SaveVariables(data);
+	SaveActionQueues(data);
 	obs_data_set_string(data, "version", g_GIT_TAG);
 	auto json = obs_data_get_json(data);
 	QString exportString(json);
@@ -369,26 +372,6 @@ bool AdvSceneSwitcher::ResolveMacroImportNameConflict(
 	return true;
 }
 
-static bool variableWithNameExists(const std::string &name)
-{
-	return !!GetVariableByName(name);
-}
-
-static void importVariables(obs_data_t *obj)
-{
-	OBSDataArrayAutoRelease array = obs_data_get_array(obj, "variables");
-	size_t count = obs_data_array_count(array);
-	for (size_t i = 0; i < count; i++) {
-		OBSDataAutoRelease data = obs_data_array_item(array, i);
-		auto var = Variable::Create();
-		var->Load(data);
-		if (variableWithNameExists(var->Name())) {
-			continue;
-		}
-		GetVariables().emplace_back(var);
-	}
-}
-
 void AdvSceneSwitcher::ImportMacros()
 {
 	QString json;
@@ -403,7 +386,8 @@ void AdvSceneSwitcher::ImportMacros()
 		ImportMacros();
 		return;
 	}
-	importVariables(data);
+	ImportVariables(data);
+	ImportQueues(data);
 
 	auto version = obs_data_get_string(data, "version");
 	if (strcmp(version, g_GIT_TAG) != 0) {
@@ -424,6 +408,7 @@ void AdvSceneSwitcher::ImportMacros()
 		OBSDataAutoRelease array_obj = obs_data_array_item(array, i);
 		auto macro = std::make_shared<Macro>();
 		macro->Load(array_obj);
+		RunPostLoadSteps();
 
 		if (macroNameExists(macro->Name()) &&
 		    !ResolveMacroImportNameConflict(macro)) {
@@ -729,6 +714,7 @@ void AdvSceneSwitcher::MacroSelectionChanged()
 		return;
 	}
 	SetEditMacro(*macro);
+	obs_frontend_save();
 }
 
 void AdvSceneSwitcher::HighlightOnChange()

lib/utils/action-queue.cpp

@@ -358,6 +358,27 @@ void LoadActionQueues(obs_data_t *obj)
 	}
 }
 
+static bool queueWithNameExists(const std::string &name)
+{
+	return !GetWeakActionQueueByName(name).expired();
+}
+
+void ImportQueues(obs_data_t *data)
+{
+	OBSDataArrayAutoRelease array =
+		obs_data_get_array(data, "actionQueues");
+	size_t count = obs_data_array_count(array);
+	for (size_t i = 0; i < count; i++) {
+		OBSDataAutoRelease arrayElement = obs_data_array_item(array, i);
+		auto queue = ActionQueue::Create();
+		queue->Load(arrayElement);
+		if (queueWithNameExists(queue->Name())) {
+			continue;
+		}
+		queues.emplace_back(queue);
+	}
+}
+
 std::weak_ptr<ActionQueue> GetWeakActionQueueByName(const std::string &name)
 {
 	for (const auto &queue : queues) {

lib/utils/action-queue.hpp

@@ -98,6 +98,7 @@ signals:
 void SetupActionQueues();
 void SaveActionQueues(obs_data_t *);
 void LoadActionQueues(obs_data_t *);
+void ImportQueues(obs_data_t *);
 std::weak_ptr<ActionQueue> GetWeakActionQueueByName(const std::string &name);
 std::weak_ptr<ActionQueue> GetWeakActionQueueByQString(const QString &name);
 std::string GetActionQueueName(const std::weak_ptr<ActionQueue> &);

lib/utils/double-slider.cpp

@@ -0,0 +1,63 @@
+#include "double-slider.hpp"
+#include <QWheelEvent>
+
+#include <cmath>
+
+namespace advss {
+
+SliderIgnoreScroll::SliderIgnoreScroll(QWidget *parent) : QSlider(parent)
+{
+	setFocusPolicy(Qt::StrongFocus);
+}
+
+SliderIgnoreScroll::SliderIgnoreScroll(Qt::Orientation orientation,
+				       QWidget *parent)
+	: QSlider(parent)
+{
+	setFocusPolicy(Qt::StrongFocus);
+	setOrientation(orientation);
+}
+
+void SliderIgnoreScroll::wheelEvent(QWheelEvent *event)
+{
+	if (!hasFocus()) {
+		event->ignore();
+	} else {
+		QSlider::wheelEvent(event);
+	}
+}
+
+DoubleSlider::DoubleSlider(QWidget *parent) : SliderIgnoreScroll(parent)
+{
+	connect(this, &DoubleSlider::valueChanged, [this](int val) {
+		emit DoubleValChanged((minVal / minStep + val) * minStep);
+	});
+}
+
+void DoubleSlider::SetDoubleConstraints(double newMin, double newMax,
+					double newStep, double val)
+{
+	minVal = newMin;
+	maxVal = newMax;
+	minStep = newStep;
+
+	double total = maxVal - minVal;
+	int intMax = int(total / minStep);
+
+	setMinimum(0);
+	setMaximum(intMax);
+	setSingleStep(1);
+	SetDoubleVal(val);
+}
+
+double DoubleSlider::DoubleValue()
+{
+	return (minVal / minStep + value()) * minStep;
+}
+
+void DoubleSlider::SetDoubleVal(double val)
+{
+	setValue(lround((val - minVal) / minStep));
+}
+
+} // namespace advss

lib/utils/double-slider.hpp

@@ -0,0 +1,40 @@
+// Based on OBS DoubleSlider and SliderIgnoreScroll implementation
+
+#pragma once
+#include "export-symbol-helper.hpp"
+
+#include <QSlider>
+
+namespace advss {
+
+class SliderIgnoreScroll : public QSlider {
+	Q_OBJECT
+
+public:
+	SliderIgnoreScroll(QWidget *parent = nullptr);
+	SliderIgnoreScroll(Qt::Orientation orientation,
+			   QWidget *parent = nullptr);
+
+protected:
+	virtual void wheelEvent(QWheelEvent *event) override;
+};
+
+class ADVSS_EXPORT DoubleSlider : public SliderIgnoreScroll {
+	Q_OBJECT
+
+	double minVal = 0, maxVal = 100, minStep = 1;
+
+public:
+	DoubleSlider(QWidget *parent = nullptr);
+
+	void SetDoubleConstraints(double newMin, double newMax, double newStep,
+				  double val);
+	double DoubleValue();
+signals:
+	void DoubleValChanged(double val);
+
+public slots:
+	void SetDoubleVal(double val);
+};
+
+} // namespace advss

lib/utils/volume-control.cpp

@@ -90,15 +90,17 @@ void VolControl::setPeakMeterType(enum obs_peak_meter_type peakMeterType)
 }
 
 VolumeSlider::VolumeSlider(obs_fader_t *fader, QWidget *parent)
-	: QSlider(parent)
+	: DoubleSlider(parent)
 {
 	fad = fader;
 }
 
 VolumeSlider::VolumeSlider(obs_fader_t *fader, Qt::Orientation orientation,
 			   QWidget *parent)
-	: QSlider(orientation, parent)
+	: DoubleSlider(parent)
 {
+	SetDoubleConstraints(0, 100, 0.01, 0);
+	setOrientation(orientation);
 	fad = fader;
 }
 
@@ -219,7 +221,6 @@ VolControl::VolControl(OBSSource source_, bool showConfig, bool vertical)
 	nameLabel->setText(sourceName);
 
 	slider->setMinimum(0);
-	slider->setMaximum(int(FADER_PRECISION));
 
 	obs_fader_add_callback(obs_fader, OBSVolumeChanged, this);
 	obs_volmeter_add_callback(obs_volmeter, OBSVolumeLevel, this);
@@ -592,7 +593,9 @@ void VolumeMeter::mousePressEvent(QMouseEvent *event)
 
 VolumeMeter::VolumeMeter(QWidget *parent, obs_volmeter_t *obs_volmeter,
 			 bool vertical)
-	: QWidget(parent), obs_volmeter(obs_volmeter), vertical(vertical)
+	: QWidget(parent),
+	  obs_volmeter(obs_volmeter),
+	  vertical(vertical)
 {
 	setAttribute(Qt::WA_OpaquePaintEvent, true);
 

lib/utils/volume-control.hpp

@@ -1,4 +1,5 @@
 #pragma once
+#include "double-slider.hpp"
 
 #include <obs.hpp>
 #include <QWidget>
@@ -284,7 +285,7 @@ private:
 	QLabel *nameLabel;
 	QLabel *volLabel;
 	VolumeMeter *volMeter;
-	QSlider *slider;
+	DoubleSlider *slider;
 	QPushButton *config = nullptr;
 	float levelTotal;
 	float levelCount;
@@ -327,10 +328,10 @@ public:
 	inline void SetContextMenu(QMenu *cm) { contextMenu = cm; }
 
 	void refreshColors();
-	QSlider *GetSlider() const { return slider; }
+	DoubleSlider *GetSlider() const { return slider; }
 };
 
-class VolumeSlider : public QSlider {
+class VolumeSlider : public DoubleSlider {
 	Q_OBJECT
 
 public:

lib/variables/variable-tab.cpp

@@ -102,7 +102,6 @@ static void removeVariableRow(QTableWidget *table, const QString &name)
 
 static void updateVaribleStatus(QTableWidget *table)
 {
-	auto lock = LockContext();
 	for (int row = 0; row < table->rowCount(); row++) {
 		auto item = table->item(row, 0);
 		if (!item) {

lib/variables/variable.cpp

@@ -187,6 +187,28 @@ void LoadVariables(obs_data_t *obj)
 	obs_data_array_release(variablesArray);
 }
 
+static bool variableWithNameExists(const std::string &name)
+{
+	return !!GetVariableByName(name);
+}
+
+void ImportVariables(obs_data_t *data)
+{
+	obs_data_array_t *array = obs_data_get_array(data, "variables");
+	size_t count = obs_data_array_count(array);
+	for (size_t i = 0; i < count; i++) {
+		obs_data_t *arrayElement = obs_data_array_item(array, i);
+		auto var = Variable::Create();
+		var->Load(arrayElement);
+		obs_data_release(arrayElement);
+		if (variableWithNameExists(var->Name())) {
+			continue;
+		}
+		GetVariables().emplace_back(var);
+	}
+	obs_data_array_release(array);
+}
+
 static void populateSaveActionSelection(QComboBox *list)
 {
 	list->addItem(

lib/variables/variable.hpp

@@ -88,6 +88,7 @@ signals:
 
 void SaveVariables(obs_data_t *obj);
 void LoadVariables(obs_data_t *obj);
+void ImportVariables(obs_data_t *obj);
 
 std::deque<std::shared_ptr<Item>> &GetVariables();
 

plugins/base/macro-action-virtual-cam.cpp

@@ -67,12 +67,12 @@ bool MacroActionVCam::Load(obs_data_t *obj)
 
 std::shared_ptr<MacroAction> MacroActionVCam::Create(Macro *m)
 {
-	return std::shared_ptr<MacroAction>();
+	return std::make_shared<MacroActionVCam>(m);
 }
 
 std::shared_ptr<MacroAction> MacroActionVCam::Copy() const
 {
-	return std::shared_ptr<MacroAction>();
+	return std::make_shared<MacroActionVCam>(*this);
 }
 
 static inline void populateActionSelection(QComboBox *list)

plugins/base/macro-condition-audio.cpp

@@ -67,7 +67,7 @@ bool MacroConditionAudio::CheckOutputCondition()
 	OBSSourceAutoRelease source =
 		obs_weak_source_get_source(_audioSource.GetSource());
 
-	double curVolume = _useDb ? _peak : DecibelToPercent(_peak);
+	double curVolume = _useDb ? _peak : DecibelToPercent(_peak) * 100;
 
 	switch (_outputCondition) {
 	case OutputCondition::ABOVE:
@@ -253,7 +253,7 @@ bool MacroConditionAudio::Save(obs_data_t *obj) const
 			 static_cast<int>(_volumeCondition));
 	obs_data_set_bool(obj, "useDb", _useDb);
 	_volumeDB.Save(obj, "volumeDB");
-	obs_data_set_int(obj, "version", 2);
+	obs_data_set_int(obj, "version", 3);
 	return true;
 }
 
@@ -294,9 +294,19 @@ bool MacroConditionAudio::Load(obs_data_t *obj)
 	_volumeCondition = static_cast<VolumeCondition>(
 		obs_data_get_int(obj, "volumeCondition"));
 	_volmeter = AddVolmeterToSource(this, _audioSource.GetSource());
-	if (obs_data_get_int(obj, "version") != 2) {
+
+	if (obs_data_get_int(obj, "version") < 2) {
+		// Set default values for dB handling
 		_useDb = false;
 		_volumeDB = 0.0;
+
+		// In previous versions the scaling happened in CheckCondition()
+		// so these values must now be converted to enable compatibility
+		// with the decibel value based checks.
+		OBSDataAutoRelease data = obs_data_get_obj(obj, "volume");
+		auto oldFixedValue = obs_data_get_int(data, "value");
+		_volumeDB = ((double)oldFixedValue / 1.7) - 60;
+		_volumePercent = DecibelToPercent(_volumeDB) * 100;
 	} else {
 		_useDb = obs_data_get_bool(obj, "useDb");
 		_volumeDB.Load(obj, "volumeDB");
@@ -416,7 +426,7 @@ MacroConditionAudioEdit::MacroConditionAudioEdit(
 	  _checkTypes(new QComboBox()),
 	  _sources(new SourceSelectionWidget(this, QStringList(), true)),
 	  _condition(new QComboBox()),
-	  _volumePercent(new VariableSpinBox()),
+	  _volumePercent(new VariableDoubleSpinBox()),
 	  _volumeDB(new VariableDoubleSpinBox),
 	  _percentDBToggle(new QPushButton),
 	  _syncOffset(new VariableSpinBox()),
@@ -444,8 +454,9 @@ MacroConditionAudioEdit::MacroConditionAudioEdit(
 			 SLOT(CheckTypeChanged(int)));
 	QWidget::connect(
 		_volumePercent,
-		SIGNAL(NumberVariableChanged(const NumberVariable<int> &)),
-		this, SLOT(VolumePercentChanged(const NumberVariable<int> &)));
+		SIGNAL(NumberVariableChanged(const NumberVariable<double> &)),
+		this,
+		SLOT(VolumePercentChanged(const NumberVariable<double> &)));
 	QWidget::connect(
 		_syncOffset,
 		SIGNAL(NumberVariableChanged(const NumberVariable<int> &)),
@@ -506,11 +517,12 @@ void MacroConditionAudioEdit::UpdateVolmeterSource()
 	auto layout = this->layout();
 	layout->addWidget(_volMeter);
 
-	QWidget::connect(_volMeter->GetSlider(), &QSlider::valueChanged,
-			 [=](int) { SyncSliderAndValueSelection(true); });
+	QWidget::connect(_volMeter->GetSlider(),
+			 &DoubleSlider::DoubleValChanged,
+			 [=](double) { SyncSliderAndValueSelection(true); });
 
 	// Slider will default to 0 so set it manually once
-	_volMeter->GetSlider()->setValue(_entryData->_volumePercent);
+	SyncSliderAndValueSelection(false);
 }
 
 void MacroConditionAudioEdit::SourceChanged(const SourceSelection &source)
@@ -531,7 +543,7 @@ void MacroConditionAudioEdit::SourceChanged(const SourceSelection &source)
 }
 
 void MacroConditionAudioEdit::VolumePercentChanged(
-	const NumberVariable<int> &vol)
+	const NumberVariable<double> &vol)
 {
 	if (_loading || !_entryData) {
 		return;
@@ -600,35 +612,35 @@ void MacroConditionAudioEdit::PercentDBClicked()
 
 void MacroConditionAudioEdit::SyncSliderAndValueSelection(bool sliderMoved)
 {
-	if (_loading || !_entryData) {
+	if (!_entryData) {
 		return;
 	}
 
 	if (sliderMoved) {
+		auto sliderPosition = _volMeter->GetSlider()->DoubleValue();
+		// Adjust to the dB scale on the volume meter widget
+		auto dBScaleValue = ((sliderPosition * 3.0) / 5.0) - 60.0;
+
 		if (_entryData->_useDb) {
-			_volumeDB->SetFixedValue(PercentToDecibel(
-				(float)_volMeter->GetSlider()->value() /
-				100.0));
+			_volumeDB->SetFixedValue(dBScaleValue);
 			const QSignalBlocker blocker(this);
 			_volumePercent->SetFixedValue(
-				_volMeter->GetSlider()->value());
+				DecibelToPercent(dBScaleValue) * 100);
 		} else {
 			_volumePercent->SetFixedValue(
-				_volMeter->GetSlider()->value());
+				DecibelToPercent(dBScaleValue) * 100);
 			const QSignalBlocker blocker(this);
-			_volumeDB->SetFixedValue(PercentToDecibel(
-				(float)_volMeter->GetSlider()->value() /
-				100.0));
+			_volumeDB->SetFixedValue(dBScaleValue);
 		}
 	} else {
 		const QSignalBlocker blocker(this);
-		if (_entryData->_useDb) {
-			_volMeter->GetSlider()->setValue(
-				DecibelToPercent(_entryData->_volumeDB) * 100);
-		} else {
-			_volMeter->GetSlider()->setValue(
-				_entryData->_volumePercent);
-		}
+		double dBValue =
+			_entryData->_useDb
+				? _entryData->_volumeDB.GetFixedValue()
+				: PercentToDecibel(_entryData->_volumePercent /
+						   100.0);
+		auto sliderPosition = (dBValue + 60.0) * 5 / 3.0;
+		_volMeter->GetSlider()->SetDoubleVal(sliderPosition);
 	}
 }
 

plugins/base/macro-condition-audio.hpp

@@ -55,11 +55,11 @@ public:
 
 	SourceSelection _audioSource;
 	bool _useDb = false;
-	NumberVariable<int> _volumePercent = 0;
-	NumberVariable<double> _volumeDB = 0.0;
-	NumberVariable<int> _syncOffset = 0;
+	DoubleVariable _volumePercent = 0;
+	DoubleVariable _volumeDB = 0.0;
+	IntVariable _syncOffset = 0;
 	obs_monitoring_type _monitorType = OBS_MONITORING_TYPE_NONE;
-	NumberVariable<double> _balance = 0.5;
+	DoubleVariable _balance = 0.5;
 	OutputCondition _outputCondition = OutputCondition::ABOVE;
 	VolumeCondition _volumeCondition = VolumeCondition::ABOVE;
 	obs_volmeter_t *_volmeter = nullptr;
@@ -97,7 +97,7 @@ public:
 
 private slots:
 	void SourceChanged(const SourceSelection &);
-	void VolumePercentChanged(const NumberVariable<int> &vol);
+	void VolumePercentChanged(const NumberVariable<double> &vol);
 	void ConditionChanged(int cond);
 	void CheckTypeChanged(int cond);
 	void SyncOffsetChanged(const NumberVariable<int> &value);
@@ -117,7 +117,7 @@ private:
 	QComboBox *_checkTypes;
 	SourceSelectionWidget *_sources;
 	QComboBox *_condition;
-	VariableSpinBox *_volumePercent;
+	VariableDoubleSpinBox *_volumePercent;
 	VariableDoubleSpinBox *_volumeDB;
 	QPushButton *_percentDBToggle;
 	VariableSpinBox *_syncOffset;

plugins/midi/midi-helpers.cpp

@@ -17,6 +17,55 @@ namespace advss {
 std::map<std::pair<MidiDeviceType, std::string>, MidiDeviceInstance *>
 	MidiDeviceInstance::devices = {};
 
+static bool setupDeviceObservers()
+{
+	static std::vector<libremidi::observer> observers;
+	for (auto api : libremidi::available_apis()) {
+		libremidi::observer_configuration cbs;
+		cbs.input_added = [=](const libremidi::input_port &p) {
+			auto dev = MidiDeviceInstance::GetDevice(p);
+			if (!dev) {
+				return;
+			}
+			blog(LOG_INFO, "MIDI input connected: %s",
+			     p.port_name.c_str());
+			dev->ClosePort();
+			dev->OpenPort();
+		};
+		cbs.input_removed = [=](const libremidi::input_port &p) {
+			auto dev = MidiDeviceInstance::GetDevice(p);
+			if (!dev) {
+				return;
+			}
+			blog(LOG_INFO, "MIDI input removed: %s",
+			     p.port_name.c_str());
+		};
+		cbs.output_added = [=](const libremidi::output_port &p) {
+			auto dev = MidiDeviceInstance::GetDevice(p);
+			if (!dev) {
+				return;
+			}
+			blog(LOG_INFO, "MIDI output connected: %s",
+			     p.port_name.c_str());
+			dev->ClosePort();
+			dev->OpenPort();
+		};
+		cbs.output_removed = [=](const libremidi::output_port &p) {
+			auto dev = MidiDeviceInstance::GetDevice(p);
+			if (!dev) {
+				return;
+			}
+			blog(LOG_INFO, "MIDI output removed: %s",
+			     p.port_name.c_str());
+		};
+		observers.emplace_back(
+			cbs, libremidi::observer_configuration_for(api));
+	}
+	return true;
+}
+
+static bool deviceObserversAreSetup = setupDeviceObservers();
+
 void MidiDeviceInstance::ResetAllDevices()
 {
 	for (auto const &[_, device] : MidiDeviceInstance::devices) {
@@ -212,8 +261,9 @@ bool MidiMessage::Matches(const MidiMessage &m) const
 	return channelMatch && noteMatch && valueMatch && typeMatch;
 }
 
-MidiDeviceInstance *MidiDeviceInstance::GetDevice(MidiDeviceType type,
-						  const std::string &name)
+MidiDeviceInstance *
+MidiDeviceInstance::GetDeviceAndOpen(MidiDeviceType type,
+				     const std::string &name)
 {
 	if (name.empty()) {
 		return nullptr;
@@ -252,6 +302,30 @@ getNameFromPortInformation(const libremidi::port_information &info)
 	return "[" + name;
 }
 
+MidiDeviceInstance *
+advss::MidiDeviceInstance::GetDevice(const libremidi::input_port &p)
+{
+	auto key = std::make_pair(MidiDeviceType::INPUT,
+				  getNameFromPortInformation(p));
+	auto it = MidiDeviceInstance::devices.find(key);
+	if (it == devices.end()) {
+		return nullptr;
+	}
+	return it->second;
+}
+
+MidiDeviceInstance *
+advss::MidiDeviceInstance::GetDevice(const libremidi::output_port &p)
+{
+	auto key = std::make_pair(MidiDeviceType::OUTPUT,
+				  getNameFromPortInformation(p));
+	auto it = MidiDeviceInstance::devices.find(key);
+	if (it == devices.end()) {
+		return nullptr;
+	}
+	return it->second;
+}
+
 static inline QStringList getInputDeviceNames()
 {
 	QStringList devices;
@@ -305,10 +379,11 @@ static std::string getPortNameFromNumber(MidiDeviceType type, int port)
 	return devices.at(port).toStdString();
 }
 
-MidiDeviceInstance *MidiDeviceInstance::GetDevice(MidiDeviceType type, int port)
+MidiDeviceInstance *MidiDeviceInstance::GetDeviceAndOpen(MidiDeviceType type,
+							 int port)
 {
 	std::string name = getPortNameFromNumber(type, port);
-	return GetDevice(type, name);
+	return GetDeviceAndOpen(type, name);
 }
 
 void MidiDevice::Save(obs_data_t *obj) const
@@ -327,13 +402,13 @@ void MidiDevice::Load(obs_data_t *obj)
 	// TODO: Remove this fallback at some point
 	if (obs_data_has_user_value(data, "port")) {
 		auto port = obs_data_get_int(data, "port");
-		_dev = MidiDeviceInstance::GetDevice(_type, port);
+		_dev = MidiDeviceInstance::GetDeviceAndOpen(_type, port);
 		if (_dev) {
 			_name = _dev->_name;
 		}
 	} else {
 		_name = obs_data_get_string(data, "portName");
-		_dev = MidiDeviceInstance::GetDevice(_type, _name);
+		_dev = MidiDeviceInstance::GetDeviceAndOpen(_type, _name);
 	}
 }
 
@@ -372,8 +447,7 @@ getInPortFromName(const std::string &name)
 
 bool MidiDeviceInstance::OpenPort()
 {
-	if ((_type == MidiDeviceType::INPUT && _in.is_port_open()) ||
-	    (_type == MidiDeviceType::OUTPUT && _out.is_port_open())) {
+	if (IsOpened()) {
 		return true;
 	}
 
@@ -437,10 +511,15 @@ bool MidiDeviceInstance::OpenPort()
 	return false;
 }
 
+bool MidiDeviceInstance::IsOpened() const
+{
+	return (_type == MidiDeviceType::INPUT && _in.is_port_open()) ||
+	       (_type == MidiDeviceType::OUTPUT && _out.is_port_open());
+}
+
 void MidiDeviceInstance::ClosePort()
 {
-	if ((_type == MidiDeviceType::INPUT && !_in.is_port_open()) ||
-	    (_type == MidiDeviceType::OUTPUT && !_out.is_port_open())) {
+	if (!IsOpened()) {
 		return;
 	}
 
@@ -542,7 +621,6 @@ MidiMessageBuffer MidiDeviceInstance::RegisterForMidiMessages()
 
 void MidiDeviceInstance::ReceiveMidiMessage(libremidi::message &&msg)
 {
-	auto lock = LockContext();
 	_dispatcher.DispatchMessage(msg);
 	vblog(LOG_INFO, "received midi: %s",
 	      MidiMessage::ToString(msg).c_str());
@@ -590,7 +668,7 @@ void MidiDeviceSelection::IdxChangedHelper(int idx)
 	}
 
 	auto name = currentText().toStdString();
-	auto devInstance = MidiDeviceInstance::GetDevice(_type, name);
+	auto devInstance = MidiDeviceInstance::GetDeviceAndOpen(_type, name);
 	if (!devInstance) {
 		DisplayMessage(obs_module_text(
 			"AdvSceneSwitcher.midi.deviceOpenFail"));

plugins/midi/midi-helpers.hpp

@@ -64,16 +64,22 @@ enum class MidiDeviceType {
 
 class MidiDeviceInstance {
 public:
-	static MidiDeviceInstance *GetDevice(MidiDeviceType type,
-					     const std::string &);
-	static MidiDeviceInstance *GetDevice(MidiDeviceType type, int port);
+	static MidiDeviceInstance *GetDeviceAndOpen(MidiDeviceType type,
+						    const std::string &);
+	static MidiDeviceInstance *GetDeviceAndOpen(MidiDeviceType type,
+						    int port);
+	static MidiDeviceInstance *GetDevice(const libremidi::input_port &p);
+	static MidiDeviceInstance *GetDevice(const libremidi::output_port &p);
+
 	static void ResetAllDevices();
 
+	bool OpenPort();
+	void ClosePort();
+
 private:
 	MidiDeviceInstance() = default;
 	~MidiDeviceInstance() = default;
-	bool OpenPort();
-	void ClosePort();
+	bool IsOpened() const;
 	bool SendMessge(const MidiMessage &);
 	[[nodiscard]] MidiMessageBuffer RegisterForMidiMessages();
 	void ReceiveMidiMessage(libremidi::message &&);