[WIP] Add Audio Mixer

rootex/core/audio/audio_bus.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include "common/common.h"
+
+class AudioBus
+{
+private:
+	String m_BusName;
+	AudioBus* m_Parent = nullptr;
+	Vector<Ref<AudioComponent>> m_AudioComponents;
+	Vector<AudioBus*> m_Children;
+	bool m_IsMaster; // really needed?
+	// TODO: change volume of components when m_Volume changes
+	float m_Volume;
+
+	AudioBus();
+	AudioBus(AudioBus&) = delete;
+	~AudioBus() = default;
+
+public:
+	void addAudioComponent(Ref<AudioComponent> cp);
+	void onVolumeChange(float delta);
+	void setParent(AudioBus* parent);
+	String getBusName() { return m_BusName; };
+	float& getBusVolume() { return m_Volume; };
+};

rootex/framework/components/audio/audio_component.cpp

@@ -28,7 +28,9 @@ AudioComponent::AudioComponent(
     , m_DependencyOnBoxColliderComponent(this)
     , m_DependencyOnCapsuleColliderComponent(this)
     , m_DependencyOnSphereColliderComponent(this)
-{
+    , m_AudioBus(nullptr) // get the master bus ptr => getMasterBus()
+{
+	// By default the audio component's bus should be master
 }
 
 RigidBodyComponent* AudioComponent::getCollider()
@@ -125,6 +127,23 @@ void AudioComponent::setLooping(bool enabled)
 	m_AudioSource->setLooping(enabled);
 }
 
+void AudioComponent::setAudioBus(AudioBus* bus)
+{
+	m_AudioBus = bus; // to be thought upon whether, using BusName here would be better or a pointer
+	bus->addAudioComponent(Ref<AudioComponent>(this));
+}
+
+void AudioComponent::changeVolume(float delta)
+{
+	if (delta > 1.0f)
+	{
+		return;
+		WARN("Wrong volume change");
+	}
+
+	m_Volume = m_Volume * (1.0f - delta);
+}
+
 void AudioComponent::draw()
 {
 	RenderSystem::GetSingleton()->submitSphere(getTransformComponent()->getAbsoluteTransform().Translation(), m_MaxDistance);
@@ -176,4 +195,17 @@ void AudioComponent::draw()
 	ImGui::DragFloat("Rolloff Factor", &m_RolloffFactor, 1.0f, 0.0f, 100.0f);
 	ImGui::DragFloat("Max Distance", &m_MaxDistance, 1.0f, 0.0f, 100.0f);
 	ImGui::DragFloat("Volume", &m_Volume, 0.01f, 0.0f, 100.0f);
+
+	// Audio mixer UI
+	if (ImGui::BeginCombo("Bus", AudioSystem::GetSingleton()->getAudioBuses()[0]->getBusName().c_str()))
+	{
+		for (auto& cp : AudioSystem::GetSingleton()->getAudioBuses())
+		{
+			if (ImGui::Selectable(cp->getBusName().c_str()))
+			{
+				setAudioBus(cp);
+			}
+		}
+		ImGui::EndCombo();
+	}
 }

rootex/framework/components/audio/audio_component.h

@@ -7,6 +7,9 @@
 #include "components/physics/box_collider_component.h"
 #include "components/physics/sphere_collider_component.h"
 #include "components/physics/capsule_collider_component.h"
+#include "systems/audio_system.h"
+
+class AudioBus;
 
 class AudioComponent : public Component
 {
@@ -22,6 +25,7 @@ class AudioComponent : public Component
 	ALfloat m_MaxDistance;
 	ALfloat m_Volume;
 	AudioSource* m_AudioSource;
+	AudioBus* m_AudioBus;
 
 protected:
 	bool m_IsPlayOnStart;
@@ -61,5 +65,8 @@ class AudioComponent : public Component
 
 	bool setupData() override;
 	JSON::json getJSON() const;
-	void draw() override;
+	void draw() override;
+
+	void setAudioBus(AudioBus* bus);
+	void changeVolume(float delta);
 };

rootex/framework/components/audio/music_component.cpp

@@ -1,70 +1,70 @@
-#include "music_component.h"
-
-DEFINE_COMPONENT(MusicComponent);
-
-MusicComponent::MusicComponent(Entity& owner, const JSON::json& data)
-    : AudioComponent(
-        owner,
-        data.value("playOnStart", false),
-        data.value("volume", 1.0f),
-        data.value("isLooping", false),
-        data.value("isAttenuated", false),
-        (AudioSource::AttenuationModel)data.value("attenuationModel", (int)AudioSource::AttenuationModel::Linear),
-        (ALfloat)data.value("rollOffFactor", 1.0f),
-        (ALfloat)data.value("referenceDistance", 1.0f),
-        (ALfloat)data.value("maxDistance", 100.0f))
-    , m_AudioFile(ResourceLoader::CreateAudioResourceFile(data.value("audio", "rootex/assets/ball.wav")))
-{
-}
-
-MusicComponent::~MusicComponent()
-{
-	m_StreamingAudioSource.reset();
-}
-
-bool MusicComponent::setupData()
-{
-	m_StreamingAudioSource.reset();
-	m_StreamingAudioBuffer.reset(new StreamingAudioBuffer(m_AudioFile));
-	m_StreamingAudioSource.reset(new StreamingAudioSource(m_StreamingAudioBuffer));
-
-	setAudioSource(m_StreamingAudioSource.get());
-
-	return AudioComponent::setupData();
-}
-
-JSON::json MusicComponent::getJSON() const
-{
-	JSON::json& j = AudioComponent::getJSON();
-
-	j["audio"] = m_AudioFile->getPath().string();
-	j["playOnStart"] = m_IsPlayOnStart;
-
-	return j;
-}
-
-void MusicComponent::setAudioFile(Ref<AudioResourceFile> audioFile)
-{
-	m_AudioFile = audioFile;
-	setupData();
-}
-
-void MusicComponent::draw()
-{
-	ImGui::Text("%s", m_AudioFile->getPath().generic_string().c_str());
-	ImGui::SameLine();
-	if (ImGui::Button("Audio File"))
-	{
-		EventManager::GetSingleton()->call(EditorEvents::EditorOpenFile, VariantVector { m_AudioFile->getPath().generic_string(), (int)m_AudioFile->getType() });
-	}
-	ImGui::SameLine();
-	if (ImGui::Button(ICON_ROOTEX_FOLDER_OPEN "##Select Music"))
-	{
-		if (Optional<String> result = OS::SelectFile(SupportedFiles.at(ResourceFile::Type::Audio), "game/assets/"))
-		{
-			setAudioFile(ResourceLoader::CreateAudioResourceFile(*result));
-		}
-	}
-
-	AudioComponent::draw();
-}
+#include "music_component.h"
+
+DEFINE_COMPONENT(MusicComponent);
+
+MusicComponent::MusicComponent(Entity& owner, const JSON::json& data)
+    : AudioComponent(
+        owner,
+        data.value("playOnStart", false),
+        data.value("volume", 1.0f),
+        data.value("isLooping", false),
+        data.value("isAttenuated", false),
+        (AudioSource::AttenuationModel)data.value("attenuationModel", (int)AudioSource::AttenuationModel::Linear),
+        (ALfloat)data.value("rollOffFactor", 1.0f),
+        (ALfloat)data.value("referenceDistance", 1.0f),
+        (ALfloat)data.value("maxDistance", 100.0f))
+    , m_AudioFile(ResourceLoader::CreateAudioResourceFile(data.value("audio", "rootex/assets/ball.wav")))
+{
+}
+
+MusicComponent::~MusicComponent()
+{
+	m_StreamingAudioSource.reset();
+}
+
+bool MusicComponent::setupData()
+{
+	m_StreamingAudioSource.reset();
+	m_StreamingAudioBuffer.reset(new StreamingAudioBuffer(m_AudioFile));
+	m_StreamingAudioSource.reset(new StreamingAudioSource(m_StreamingAudioBuffer));
+
+	setAudioSource(m_StreamingAudioSource.get());
+
+	return AudioComponent::setupData();
+}
+
+JSON::json MusicComponent::getJSON() const
+{
+	JSON::json& j = AudioComponent::getJSON();
+
+	j["audio"] = m_AudioFile->getPath().string();
+	j["playOnStart"] = m_IsPlayOnStart;
+
+	return j;
+}
+
+void MusicComponent::setAudioFile(Ref<AudioResourceFile> audioFile)
+{
+	m_AudioFile = audioFile;
+	setupData();
+}
+
+void MusicComponent::draw()
+{
+	ImGui::Text("%s", m_AudioFile->getPath().generic_string().c_str());
+	ImGui::SameLine();
+	if (ImGui::Button("Audio File"))
+	{
+		EventManager::GetSingleton()->call(EditorEvents::EditorOpenFile, VariantVector { m_AudioFile->getPath().generic_string(), (int)m_AudioFile->getType() });
+	}
+	ImGui::SameLine();
+	if (ImGui::Button(ICON_ROOTEX_FOLDER_OPEN "##Select Music"))
+	{
+		if (Optional<String> result = OS::SelectFile(SupportedFiles.at(ResourceFile::Type::Audio), "game/assets/"))
+		{
+			setAudioFile(ResourceLoader::CreateAudioResourceFile(*result));
+		}
+	}
+
+	AudioComponent::draw();
+}

rootex/framework/systems/audio_system.cpp

@@ -144,6 +144,69 @@ void AudioSystem::end()
 		smc.getAudioSource()->stop();
 	}
 }
+void AudioSystem::addNewBus()
+{
+	// adds a new bus to the vector and the tree
+}
+
+void AudioSystem::removeBus(AudioBus* bus)
+{
+	// removes an audio bus from the vector and the tree
+}
+
+AudioBus::AudioBus()
+    : m_Volume(100.0f)
+    , m_BusName("Bus " + AudioSystem::GetSingleton()->getAudioBuses().size()) // naming logic to be seen
+    , m_Parent(nullptr) // if not the first bus, then we need to see how to assign this to the master bus in the starting
+    , m_IsMaster(false)
+{
+	m_AudioComponents.clear();
+	m_Children.clear();
+}
+
+void AudioBus::addAudioComponent(Ref<AudioComponent> cp)
+{
+	m_AudioComponents.push_back(cp);
+}
+
+void AudioSystem::draw()
+{
+	System::draw();
+	for (int i = 0; i < m_Buses.size(); i++)
+	{
+		AudioBus* bus = m_Buses[i];
+		ImGui::Text(bus->getBusName().c_str());
+
+		if (ImGui::Button(ICON_ROOTEX_MINUS "##Remove Bus"))
+		{
+			removeBus(bus);
+		}
+
+		// volume of the bus
+		ImGui::DragFloat("Volume", &bus->getBusVolume(), 1.0f, 0.0f, 100.0f);
+
+		// selecting the parent
+		if (ImGui::BeginCombo("Parent", m_Buses[0]->getBusName().c_str()))
+		{
+			for (int j = 0; j < i; j++)
+			{
+				AudioBus* cp = m_Buses[j];
+				if (ImGui::Selectable(cp->getBusName().c_str()))
+				{
+					bus->setParent(cp);
+				}
+			}
+			ImGui::EndCombo();
+		}
+	}
+
+	if (ImGui::Button(ICON_ROOTEX_PLUS "##Add Bus"))
+	{
+		addNewBus();
+	}
+
+	ImGui::Text("AudioMixerSystem");
+}
 
 void AudioSystem::setListener(AudioListenerComponent* listenerComponent)
 {
@@ -187,4 +250,25 @@ void AudioSystem::shutDown()
 AudioSystem::AudioSystem()
     : System("AudioSystem", UpdateOrder::Async, true)
 {
+	m_Buses.clear();
+	m_Buses.push_back(nullptr); // add the master audio bus here => new AudioBus(is_Master = true)
+}
+
+void AudioBus::onVolumeChange(float delta)
+{
+	for (auto& ac : m_AudioComponents)
+	{
+		ac->changeVolume(delta);
+		// the fraction of change is to be decided
+	}
+
+	for (auto& child : m_Children)
+	{
+		child->onVolumeChange(delta);
+	}
+}
+
+void AudioBus::setParent(AudioBus* parent)
+{
+	m_Parent = parent;
 }