Qt: Sync fast forward volume

Implemented a checkbox in the Audio Settings Widget that allows the user to enable and disable the audio volume synchronization between the standard volume and the fast forward volume
- Volume synchronization is enabled by default. In that state, the fast-forward volume slider and reset button are disabled, and the fast-forward volume value is equal to the standard volume value
- When volume synchronization is disabled, the fast-forward volume slider and reset button are re-enabled, and work independently

Additional synchronization behavior:
- Adjustments on the standard volume will only affect the fast-forward volume when syncVolume is enabled
- Whenever the volume synchronization is enabled, it will update the fast-forward volume to make it match the current standard volume value
- The standard volume reset button also resets the fast-forward volume if the volume synchronization is enabled

Author: BarretoJuan

pcsx2-qt/Settings/AudioSettingsWidget.cpp

@@ -76,17 +76,33 @@ AudioSettingsWidget::AudioSettingsWidget(SettingsWindow* settings_dialog, QWidge
 		m_ui.standardVolume->setValue(dialog()->getEffectiveIntValue("SPU2/Output", "StandardVolume", 100));
 		m_ui.fastForwardVolume->setValue(dialog()->getEffectiveIntValue("SPU2/Output", "FastForwardVolume", 100));
 		m_ui.muted->setChecked(dialog()->getEffectiveBoolValue("SPU2/Output", "OutputMuted", false));
+		m_ui.syncVolume->setChecked(dialog()->getEffectiveBoolValue("SPU2/Output", "SyncVolume", true));
 		connect(m_ui.standardVolume, &QSlider::valueChanged, this, &AudioSettingsWidget::onStandardVolumeChanged);
 		connect(m_ui.fastForwardVolume, &QSlider::valueChanged, this, &AudioSettingsWidget::onFastForwardVolumeChanged);
 		connect(m_ui.muted, &QCheckBox::checkStateChanged, this, &AudioSettingsWidget::onOutputMutedChanged);
+		connect(m_ui.syncVolume, &QCheckBox::checkStateChanged, this, &AudioSettingsWidget::onVolumeSyncChanged);
 		updateVolumeLabel();
 	}
 	else
 	{
 		SettingWidgetBinder::BindWidgetAndLabelToIntSetting(sif, m_ui.standardVolume, m_ui.standardVolumeLabel, tr("%"), "SPU2/Output", "StandardVolume", 100);
 		SettingWidgetBinder::BindWidgetAndLabelToIntSetting(sif, m_ui.fastForwardVolume, m_ui.fastForwardVolumeLabel, tr("%"), "SPU2/Output", "FastForwardVolume", 100);
 		SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.muted, "SPU2/Output", "OutputMuted", false);
+		SettingWidgetBinder::BindWidgetToBoolSetting(sif, m_ui.syncVolume, "SPU2/Output", "SyncVolume", true);
+		connect(m_ui.standardVolume, &QSlider::valueChanged, this, [this](const int new_value) {
+			// only synchronize the standard and fast-forward volume is the sync volume checkboxed is ticked
+			if (dialog()->getEffectiveBoolValue("SPU2/Output", "SyncVolume", true))
+				m_ui.fastForwardVolume->setValue(new_value);
+		});
+		connect(m_ui.syncVolume, &QCheckBox::checkStateChanged, this, [this]() {
+			// re-sync the fast-forward volume when volume sync is enabled
+    		if (dialog()->getEffectiveBoolValue("SPU2/Output", "SyncVolume", true))
+        		m_ui.fastForwardVolume->setValue(m_ui.standardVolume->value());
+
+    		updateVolumeSyncState();
+		});
 	}
+	updateVolumeSyncState();
 	connect(m_ui.resetStandardVolume, &QToolButton::clicked, this, [this]() { resetVolume(false); });
 	connect(m_ui.resetFastForwardVolume, &QToolButton::clicked, this, [this]() { resetVolume(true); });
 
@@ -109,6 +125,8 @@ AudioSettingsWidget::AudioSettingsWidget(SettingsWindow* settings_dialog, QWidge
 		tr("Controls the volume of the audio played on the host when fast forwarding."));
 	dialog()->registerWidgetHelp(m_ui.muted, tr("Mute All Sound"), tr("Unchecked"),
 		tr("Prevents the emulator from producing any audible sound."));
+	dialog()->registerWidgetHelp(m_ui.syncVolume, tr("Sync Volume"), tr("Checked"),
+		tr("Synchronizes the fast-forward volume of the audio to the standard volume."));
 	dialog()->registerWidgetHelp(m_ui.expansionMode, tr("Expansion Mode"), tr("Disabled (Stereo)"),
 		tr("Determines how audio is expanded from stereo to surround for supported games. This "
 		   "includes games that support Dolby Pro Logic/Pro Logic II."));
@@ -308,6 +326,15 @@ void AudioSettingsWidget::onStandardVolumeChanged(const int new_value)
 	// only called for base settings
 	pxAssert(!dialog()->isPerGameSettings());
 	Host::SetBaseIntSettingValue("SPU2/Output", "StandardVolume", new_value);
+
+	// only synchronize the standard and fast-forward volume is the sync volume checkboxed is ticked
+	const bool syncVolume = dialog()->getEffectiveBoolValue("SPU2/Output", "SyncVolume", true);
+	if (syncVolume) {
+		QSignalBlocker sb(m_ui.fastForwardVolume);
+		m_ui.fastForwardVolume->setValue(new_value);
+		Host::SetBaseIntSettingValue("SPU2/Output", "FastForwardVolume", new_value);
+	}
+
 	Host::CommitBaseSettingChanges();
 	g_emu_thread->applySettings();
 
@@ -336,6 +363,38 @@ void AudioSettingsWidget::onOutputMutedChanged(const int new_state)
 	g_emu_thread->applySettings();
 }
 
+void AudioSettingsWidget::onVolumeSyncChanged(const int new_state)
+{
+	// only called for base settings
+	pxAssert(!dialog()->isPerGameSettings());
+
+	const bool syncVolume = (new_state != 0);
+	Host::SetBaseBoolSettingValue("SPU2/Output", "SyncVolume", syncVolume);
+
+	// re-sync the fast-forward volume when volume sync is enabled
+    if (syncVolume)
+    {
+        const int standard_volume = m_ui.standardVolume->value();
+        QSignalBlocker sb(m_ui.fastForwardVolume);
+        m_ui.fastForwardVolume->setValue(standard_volume);
+        Host::SetBaseIntSettingValue("SPU2/Output", "FastForwardVolume", standard_volume);
+        updateVolumeLabel();
+    }
+
+	Host::CommitBaseSettingChanges();
+	updateVolumeSyncState();
+	g_emu_thread->applySettings();
+}
+
+void AudioSettingsWidget::updateVolumeSyncState()
+{
+	// disables the fast forward volume slider and reset button if volume synchronization is enabled
+	// re-enables it when the synchronization is deactivated 
+	const bool syncVolume = dialog()->getEffectiveBoolValue("SPU2/Output", "SyncVolume", true);
+	m_ui.fastForwardVolume->setEnabled(!syncVolume);
+	m_ui.resetFastForwardVolume->setEnabled(!syncVolume);
+}
+
 void AudioSettingsWidget::onExpansionSettingsClicked()
 {
 	QDialog dlg(QtUtils::GetRootWidget(this));
@@ -484,7 +543,18 @@ void AudioSettingsWidget::resetVolume(const bool fast_forward)
 	QSlider* const slider = fast_forward ? m_ui.fastForwardVolume : m_ui.standardVolume;
 	QLabel* const label = fast_forward ? m_ui.fastForwardVolumeLabel : m_ui.standardVolumeLabel;
 
-	if (dialog()->isPerGameSettings())
+	const bool syncVolume = dialog()->getEffectiveBoolValue("SPU2/Output", "SyncVolume", true);
+	const bool perGame = dialog()->isPerGameSettings();
+
+	resetVolumeAction(perGame, key, slider, label);
+
+	if (syncVolume && !fast_forward) {
+		resetVolumeAction(perGame, "FastForwardVolume", m_ui.fastForwardVolume, m_ui.fastForwardVolumeLabel);
+	}
+}
+
+	void AudioSettingsWidget::resetVolumeAction(bool per_game, const char* key, QSlider* slider, QLabel* label) {
+	if (per_game)
 	{
 		dialog()->removeSettingValue("SPU2/Output", key);
 

pcsx2-qt/Settings/AudioSettingsWidget.h

@@ -30,6 +30,9 @@ private Q_SLOTS:
 	void onStandardVolumeChanged(const int new_value);
 	void onFastForwardVolumeChanged(const int new_value);
 	void onOutputMutedChanged(const int new_state);
+	void onVolumeSyncChanged(const int new_state);
+	void updateVolumeSyncState();
+	void resetVolumeAction(bool per_game, const char* key, QSlider* slider, QLabel* label);
 
 	void onExpansionSettingsClicked();
 	void onStretchSettingsClicked();

pcsx2-qt/Settings/AudioSettingsWidget.ui

@@ -365,6 +365,13 @@
         </property>
        </widget>
       </item>
+      <item row="2" column="1">
+       <widget class="QCheckBox" name="syncVolume">
+        <property name="text">
+         <string>Sync Volume</string>
+        </property>
+       </widget>
+      </item>
      </layout>
     </widget>
    </item>