UI: Allow hiding/unhiding sources in the mixer

Allows the ability to hide/unhide sources in the mixer that the user
doesn't care about or doesn't necessarily want to see (such as video
sources that have audio but don't have any audio playing).  If all
sources are hidden, the user can right-click the mixer's empty area and
choose "unhide all" via a context menu.

Closes jp9000/obs-studio#1002

UI/data/locale/en-US.ini

@@ -43,6 +43,7 @@ Clear="Clear"
 Revert="Revert"
 Show="Show"
 Hide="Hide"
+UnhideAll="Unhide All"
 Untitled="Untitled"
 New="New"
 Duplicate="Duplicate"
@@ -72,6 +73,7 @@ RemuxRecordings="Remux Recordings"
 Next="Next"
 Back="Back"
 Defaults="Defaults"
+HideMixer="Hide in Mixer"
 
 # warning if program already open
 AlreadyRunning.Title="OBS is already running"

UI/forms/OBSBasic.ui

@@ -602,13 +602,16 @@
       <number>4</number>
      </property>
      <item>
-      <widget class="VScrollArea" name="scrollArea">
+      <widget class="VScrollArea" name="mixerScrollArea">
        <property name="minimumSize">
         <size>
          <width>220</width>
          <height>0</height>
         </size>
        </property>
+       <property name="contextMenuPolicy">
+        <enum>Qt::CustomContextMenu</enum>
+       </property>
        <property name="frameShape">
         <enum>QFrame::StyledPanel</enum>
        </property>

UI/window-basic-main.cpp

@@ -2186,6 +2186,22 @@ void OBSBasic::SelectSceneItem(OBSScene scene, OBSSceneItem item, bool select)
 	}
 }
 
+static inline bool SourceMixerHidden(obs_source_t *source)
+{
+	obs_data_t *priv_settings = obs_source_get_private_settings(source);
+	bool hidden = obs_data_get_bool(priv_settings, "mixer_hidden");
+	obs_data_release(priv_settings);
+
+	return hidden;
+}
+
+static inline void SetSourceMixerHidden(obs_source_t *source, bool hidden)
+{
+	obs_data_t *priv_settings = obs_source_get_private_settings(source);
+	obs_data_set_bool(priv_settings, "mixer_hidden", hidden);
+	obs_data_release(priv_settings);
+}
+
 void OBSBasic::GetAudioSourceFilters()
 {
 	QAction *action = reinterpret_cast<QAction*>(sender());
@@ -2204,14 +2220,78 @@ void OBSBasic::GetAudioSourceProperties()
 	CreatePropertiesWindow(source);
 }
 
+void OBSBasic::HideAudioControl()
+{
+	QAction *action = reinterpret_cast<QAction*>(sender());
+	VolControl *vol = action->property("volControl").value<VolControl*>();
+	obs_source_t *source = vol->GetSource();
+
+	if (!SourceMixerHidden(source)) {
+		SetSourceMixerHidden(source, true);
+		DeactivateAudioSource(source);
+	}
+}
+
+void OBSBasic::UnhideAllAudioControls()
+{
+	auto UnhideAudioMixer = [this] (obs_source_t *source) /* -- */
+	{
+		if (!obs_source_active(source))
+			return true;
+		if (!SourceMixerHidden(source))
+			return true;
+
+		SetSourceMixerHidden(source, false);
+		ActivateAudioSource(source);
+		return true;
+	};
+
+	using UnhideAudioMixer_t = decltype(UnhideAudioMixer);
+
+	auto PreEnum = [] (void *data, obs_source_t *source) -> bool /* -- */
+	{
+		return (*reinterpret_cast<UnhideAudioMixer_t *>(data))(source);
+	};
+
+	obs_enum_sources(PreEnum, &UnhideAudioMixer);
+}
+
+void OBSBasic::ToggleHideMixer()
+{
+	OBSSceneItem item = GetCurrentSceneItem();
+	OBSSource source = obs_sceneitem_get_source(item);
+
+	if (!SourceMixerHidden(source)) {
+		SetSourceMixerHidden(source, true);
+		DeactivateAudioSource(source);
+	} else {
+		SetSourceMixerHidden(source, false);
+		ActivateAudioSource(source);
+	}
+}
+
 void OBSBasic::VolControlContextMenu()
 {
 	VolControl *vol = reinterpret_cast<VolControl*>(sender());
 
+	/* ------------------- */
+
+	QAction hideAction(QTStr("Hide"), this);
+	QAction unhideAllAction(QTStr("UnhideAll"), this);
+
 	QAction filtersAction(QTStr("Filters"), this);
 	QAction propertiesAction(QTStr("Properties"), this);
 	QAction advPropAction(QTStr("Basic.MainMenu.Edit.AdvAudio"), this);
 
+	/* ------------------- */
+
+	connect(&hideAction, &QAction::triggered,
+			this, &OBSBasic::HideAudioControl,
+			Qt::DirectConnection);
+	connect(&unhideAllAction, &QAction::triggered,
+			this, &OBSBasic::UnhideAllAudioControls,
+			Qt::DirectConnection);
+
 	connect(&filtersAction, &QAction::triggered,
 			this, &OBSBasic::GetAudioSourceFilters,
 			Qt::DirectConnection);
@@ -2222,20 +2302,45 @@ void OBSBasic::VolControlContextMenu()
 			this, &OBSBasic::on_actionAdvAudioProperties_triggered,
 			Qt::DirectConnection);
 
+	/* ------------------- */
+
+	hideAction.setProperty("volControl",
+			QVariant::fromValue<VolControl*>(vol));
+
 	filtersAction.setProperty("volControl",
 			QVariant::fromValue<VolControl*>(vol));
 	propertiesAction.setProperty("volControl",
 			QVariant::fromValue<VolControl*>(vol));
 
+	/* ------------------- */
+
 	QMenu popup(this);
+	popup.addAction(&unhideAllAction);
+	popup.addAction(&hideAction);
+	popup.addSeparator();
 	popup.addAction(&filtersAction);
 	popup.addAction(&propertiesAction);
 	popup.addAction(&advPropAction);
 	popup.exec(QCursor::pos());
 }
 
+void OBSBasic::on_mixerScrollArea_customContextMenuRequested()
+{
+	QAction unhideAllAction(QTStr("UnhideAll"), this);
+	connect(&unhideAllAction, &QAction::triggered,
+			this, &OBSBasic::UnhideAllAudioControls,
+			Qt::DirectConnection);
+
+	QMenu popup(this);
+	popup.addAction(&unhideAllAction);
+	popup.exec(QCursor::pos());
+}
+
 void OBSBasic::ActivateAudioSource(OBSSource source)
 {
+	if (SourceMixerHidden(source))
+		return;
+
 	VolControl *vol = new VolControl(source, true);
 
 	vol->setContextMenuPolicy(Qt::CustomContextMenu);
@@ -3519,6 +3624,8 @@ void OBSBasic::CreateSourcePopupMenu(QListWidgetItem *item, bool preview)
 		uint32_t flags = obs_source_get_output_flags(source);
 		bool isAsyncVideo = (flags & OBS_SOURCE_ASYNC_VIDEO) ==
 			OBS_SOURCE_ASYNC_VIDEO;
+		bool hasAudio = (flags & OBS_SOURCE_AUDIO) ==
+			OBS_SOURCE_AUDIO;
 		QAction *action;
 
 		popup.addAction(QTStr("Rename"), this,
@@ -3541,6 +3648,15 @@ void OBSBasic::CreateSourcePopupMenu(QListWidgetItem *item, bool preview)
 		popup.addAction(sourceWindow);
 
 		popup.addSeparator();
+
+		if (hasAudio) {
+			QAction *actionHideMixer = popup.addAction(
+					QTStr("HideMixer"),
+					this, SLOT(ToggleHideMixer()));
+			actionHideMixer->setCheckable(true);
+			actionHideMixer->setChecked(SourceMixerHidden(source));
+		}
+
 		if (isAsyncVideo) {
 			popup.addMenu(AddDeinterlacingMenu(source));
 			popup.addSeparator();

UI/window-basic-main.hpp

@@ -429,6 +429,12 @@ private slots:
 
 	void ToggleShowHide();
 
+	void HideAudioControl();
+	void UnhideAllAudioControls();
+	void ToggleHideMixer();
+
+	void on_mixerScrollArea_customContextMenuRequested();
+
 	void on_actionCopySource_triggered();
 	void on_actionPasteRef_triggered();
 	void on_actionPasteDup_triggered();