1 files changed, 150 insertions, 229 deletions

diff --git a/scene/audio/audio_stream_player.cpp b/scene/audio/audio_stream_player.cpp
index f612944a62..0334ba667b 100644
--- a/scene/audio/audio_stream_player.cpp
+++ b/scene/audio/audio_stream_player.cpp
@@ -5,8 +5,8 @@
 /*                           GODOT ENGINE                                */
 /*                      https://godotengine.org                          */
 /*************************************************************************/
-/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
-/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
 /*                                                                       */
 /* Permission is hereby granted, free of charge, to any person obtaining */
 /* a copy of this software and associated documentation files (the       */
@@ -30,135 +30,41 @@
 
 #include "audio_stream_player.h"
 
-#include "core/engine.h"
-
-void AudioStreamPlayer::_mix_to_bus(const AudioFrame *p_frames, int p_amount) {
-
-	int bus_index = AudioServer::get_singleton()->thread_find_bus_index(bus);
-
-	AudioFrame *targets[4] = { nullptr, nullptr, nullptr, nullptr };
-
-	if (AudioServer::get_singleton()->get_speaker_mode() == AudioServer::SPEAKER_MODE_STEREO) {
-		targets[0] = AudioServer::get_singleton()->thread_get_channel_mix_buffer(bus_index, 0);
-	} else {
-		switch (mix_target) {
-			case MIX_TARGET_STEREO: {
-				targets[0] = AudioServer::get_singleton()->thread_get_channel_mix_buffer(bus_index, 0);
-			} break;
-			case MIX_TARGET_SURROUND: {
-				for (int i = 0; i < AudioServer::get_singleton()->get_channel_count(); i++) {
-					targets[i] = AudioServer::get_singleton()->thread_get_channel_mix_buffer(bus_index, i);
-				}
-			} break;
-			case MIX_TARGET_CENTER: {
-				targets[0] = AudioServer::get_singleton()->thread_get_channel_mix_buffer(bus_index, 1);
-			} break;
-		}
-	}
-
-	for (int c = 0; c < 4; c++) {
-		if (!targets[c])
-			break;
-		for (int i = 0; i < p_amount; i++) {
-			targets[c][i] += p_frames[i];
-		}
-	}
-}
-
-void AudioStreamPlayer::_mix_internal(bool p_fadeout) {
-
-	//get data
-	AudioFrame *buffer = mix_buffer.ptrw();
-	int buffer_size = mix_buffer.size();
-
-	if (p_fadeout) {
-		// Short fadeout ramp
-		buffer_size = MIN(buffer_size, 128);
-	}
-
-	stream_playback->mix(buffer, pitch_scale, buffer_size);
-
-	//multiply volume interpolating to avoid clicks if this changes
-	float target_volume = p_fadeout ? -80.0 : volume_db;
-	float vol = Math::db2linear(mix_volume_db);
-	float vol_inc = (Math::db2linear(target_volume) - vol) / float(buffer_size);
-
-	for (int i = 0; i < buffer_size; i++) {
-		buffer[i] *= vol;
-		vol += vol_inc;
-	}
-
-	//set volume for next mix
-	mix_volume_db = target_volume;
-
-	_mix_to_bus(buffer, buffer_size);
-}
-
-void AudioStreamPlayer::_mix_audio() {
-
-	if (use_fadeout) {
-		_mix_to_bus(fadeout_buffer.ptr(), fadeout_buffer.size());
-		use_fadeout = false;
-	}
-
-	if (!stream_playback.is_valid() || !active ||
-			(stream_paused && !stream_paused_fade)) {
-		return;
-	}
-
-	if (stream_paused) {
-		if (stream_paused_fade) {
-			_mix_internal(true);
-			stream_paused_fade = false;
-		}
-		return;
-	}
-
-	if (setstop) {
-		_mix_internal(true);
-		stream_playback->stop();
-		setstop = false;
-	}
-
-	if (setseek >= 0.0 && !stop_has_priority) {
-		if (stream_playback->is_playing()) {
-
-			//fade out to avoid pops
-			_mix_internal(true);
-		}
-
-		stream_playback->start(setseek);
-		setseek = -1.0; //reset seek
-		mix_volume_db = volume_db; //reset ramp
-	}
-
-	stop_has_priority = false;
-
-	_mix_internal(false);
-}
+#include "core/config/engine.h"
+#include "core/math/audio_frame.h"
+#include "servers/audio_server.h"
 
 void AudioStreamPlayer::_notification(int p_what) {
-
 	if (p_what == NOTIFICATION_ENTER_TREE) {
-
-		AudioServer::get_singleton()->add_callback(_mix_audios, this);
 		if (autoplay && !Engine::get_singleton()->is_editor_hint()) {
 			play();
 		}
 	}
 
 	if (p_what == NOTIFICATION_INTERNAL_PROCESS) {
-
-		if (!active || (setseek < 0 && !stream_playback->is_playing())) {
-			active = false;
+		Vector<Ref<AudioStreamPlayback>> playbacks_to_remove;
+		for (Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+			if (playback.is_valid() && !AudioServer::get_singleton()->is_playback_active(playback) && !AudioServer::get_singleton()->is_playback_paused(playback)) {
+				emit_signal(SNAME("finished"));
+				playbacks_to_remove.push_back(playback);
+			}
+		}
+		// Now go through and remove playbacks that have finished. Removing elements from a Vector in a range based for is asking for trouble.
+		for (Ref<AudioStreamPlayback> &playback : playbacks_to_remove) {
+			stream_playbacks.erase(playback);
+		}
+		if (!playbacks_to_remove.is_empty() && stream_playbacks.is_empty()) {
+			// This node is no longer actively playing audio.
+			active.clear();
 			set_process_internal(false);
-			emit_signal("finished");
 		}
 	}
 
 	if (p_what == NOTIFICATION_EXIT_TREE) {
-
-		AudioServer::get_singleton()->remove_callback(_mix_audios, this);
+		for (Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+			AudioServer::get_singleton()->stop_playback_stream(playback);
+		}
+		stream_playbacks.clear();
 	}
 
 	if (p_what == NOTIFICATION_PAUSED) {
@@ -174,188 +80,212 @@ void AudioStreamPlayer::_notification(int p_what) {
 }
 
 void AudioStreamPlayer::set_stream(Ref<AudioStream> p_stream) {
-
-	AudioServer::get_singleton()->lock();
-
-	if (active && stream_playback.is_valid() && !stream_paused) {
-		//changing streams out of the blue is not a great idea, but at least
-		//lets try to somehow avoid a click
-
-		AudioFrame *buffer = fadeout_buffer.ptrw();
-		int buffer_size = fadeout_buffer.size();
-
-		stream_playback->mix(buffer, pitch_scale, buffer_size);
-
-		//multiply volume interpolating to avoid clicks if this changes
-		float target_volume = -80.0;
-		float vol = Math::db2linear(mix_volume_db);
-		float vol_inc = (Math::db2linear(target_volume) - vol) / float(buffer_size);
-
-		for (int i = 0; i < buffer_size; i++) {
-			buffer[i] *= vol;
-			vol += vol_inc;
-		}
-
-		use_fadeout = true;
-	}
-
-	mix_buffer.resize(AudioServer::get_singleton()->thread_get_mix_buffer_size());
-
-	if (stream_playback.is_valid()) {
-		stream_playback.unref();
-		stream.unref();
-		active = false;
-		setseek = -1;
-		setstop = false;
-	}
-
-	if (p_stream.is_valid()) {
-		stream = p_stream;
-		stream_playback = p_stream->instance_playback();
-	}
-
-	AudioServer::get_singleton()->unlock();
-
-	if (p_stream.is_valid() && stream_playback.is_null()) {
-		stream.unref();
-	}
+	stop();
+	stream = p_stream;
 }
 
 Ref<AudioStream> AudioStreamPlayer::get_stream() const {
-
 	return stream;
 }
 
 void AudioStreamPlayer::set_volume_db(float p_volume) {
-
 	volume_db = p_volume;
+
+	Vector<AudioFrame> volume_vector = _get_volume_vector();
+	for (Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+		AudioServer::get_singleton()->set_playback_all_bus_volumes_linear(playback, volume_vector);
+	}
 }
-float AudioStreamPlayer::get_volume_db() const {
 
+float AudioStreamPlayer::get_volume_db() const {
 	return volume_db;
 }
 
 void AudioStreamPlayer::set_pitch_scale(float p_pitch_scale) {
 	ERR_FAIL_COND(p_pitch_scale <= 0.0);
 	pitch_scale = p_pitch_scale;
+
+	for (Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+		AudioServer::get_singleton()->set_playback_pitch_scale(playback, pitch_scale);
+	}
 }
+
 float AudioStreamPlayer::get_pitch_scale() const {
 	return pitch_scale;
 }
 
-void AudioStreamPlayer::play(float p_from_pos) {
+void AudioStreamPlayer::set_max_polyphony(int p_max_polyphony) {
+	if (p_max_polyphony > 0) {
+		max_polyphony = p_max_polyphony;
+	}
+}
 
-	if (stream_playback.is_valid()) {
-		//mix_volume_db = volume_db; do not reset volume ramp here, can cause clicks
-		setseek = p_from_pos;
-		stop_has_priority = false;
-		active = true;
-		set_process_internal(true);
+int AudioStreamPlayer::get_max_polyphony() const {
+	return max_polyphony;
+}
+
+void AudioStreamPlayer::play(float p_from_pos) {
+	if (stream.is_null()) {
+		return;
+	}
+	ERR_FAIL_COND_MSG(!is_inside_tree(), "Playback can only happen when a node is inside the scene tree");
+	if (stream->is_monophonic() && is_playing()) {
+		stop();
+	}
+	Ref<AudioStreamPlayback> stream_playback = stream->instance_playback();
+	ERR_FAIL_COND_MSG(stream_playback.is_null(), "Failed to instantiate playback.");
+
+	AudioServer::get_singleton()->start_playback_stream(stream_playback, bus, _get_volume_vector(), p_from_pos);
+	stream_playbacks.push_back(stream_playback);
+	active.set();
+	set_process_internal(true);
+	while (stream_playbacks.size() > max_polyphony) {
+		AudioServer::get_singleton()->stop_playback_stream(stream_playbacks[0]);
+		stream_playbacks.remove(0);
 	}
 }
 
 void AudioStreamPlayer::seek(float p_seconds) {
-
-	if (stream_playback.is_valid()) {
-		setseek = p_seconds;
+	if (is_playing()) {
+		stop();
+		play(p_seconds);
 	}
 }
 
 void AudioStreamPlayer::stop() {
-
-	if (stream_playback.is_valid() && active) {
-		setstop = true;
-		stop_has_priority = true;
+	for (Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+		AudioServer::get_singleton()->stop_playback_stream(playback);
 	}
+	stream_playbacks.clear();
+	active.clear();
+	set_process_internal(false);
 }
 
 bool AudioStreamPlayer::is_playing() const {
-
-	if (stream_playback.is_valid()) {
-		return active && !setstop; //&& stream_playback->is_playing();
+	for (const Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+		if (AudioServer::get_singleton()->is_playback_active(playback)) {
+			return true;
+		}
 	}
-
 	return false;
 }
 
 float AudioStreamPlayer::get_playback_position() {
-
-	if (stream_playback.is_valid()) {
-		return stream_playback->get_playback_position();
+	// Return the playback position of the most recently started playback stream.
+	if (!stream_playbacks.is_empty()) {
+		return AudioServer::get_singleton()->get_playback_position(stream_playbacks[stream_playbacks.size() - 1]);
 	}
-
 	return 0;
 }
 
 void AudioStreamPlayer::set_bus(const StringName &p_bus) {
-
-	//if audio is active, must lock this
-	AudioServer::get_singleton()->lock();
 	bus = p_bus;
-	AudioServer::get_singleton()->unlock();
+	for (const Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+		AudioServer::get_singleton()->set_playback_bus_exclusive(playback, p_bus, _get_volume_vector());
+	}
 }
-StringName AudioStreamPlayer::get_bus() const {
 
+StringName AudioStreamPlayer::get_bus() const {
 	for (int i = 0; i < AudioServer::get_singleton()->get_bus_count(); i++) {
-		if (AudioServer::get_singleton()->get_bus_name(i) == bus) {
+		if (AudioServer::get_singleton()->get_bus_name(i) == String(bus)) {
 			return bus;
 		}
 	}
-	return "Master";
+	return SNAME("Master");
 }
 
 void AudioStreamPlayer::set_autoplay(bool p_enable) {
-
 	autoplay = p_enable;
 }
-bool AudioStreamPlayer::is_autoplay_enabled() {
 
+bool AudioStreamPlayer::is_autoplay_enabled() {
 	return autoplay;
 }
 
 void AudioStreamPlayer::set_mix_target(MixTarget p_target) {
-
 	mix_target = p_target;
 }
 
 AudioStreamPlayer::MixTarget AudioStreamPlayer::get_mix_target() const {
-
 	return mix_target;
 }
 
 void AudioStreamPlayer::_set_playing(bool p_enable) {
-
-	if (p_enable)
+	if (p_enable) {
 		play();
-	else
+	} else {
 		stop();
+	}
 }
-bool AudioStreamPlayer::_is_active() const {
 
-	return active;
+bool AudioStreamPlayer::_is_active() const {
+	for (const Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+		if (AudioServer::get_singleton()->is_playback_active(playback)) {
+			return true;
+		}
+	}
+	return false;
 }
 
 void AudioStreamPlayer::set_stream_paused(bool p_pause) {
-
-	if (p_pause != stream_paused) {
-		stream_paused = p_pause;
-		stream_paused_fade = p_pause;
+	// TODO this does not have perfect recall, fix that maybe? If there are zero playbacks registered with the AudioServer, this bool isn't persisted.
+	for (Ref<AudioStreamPlayback> &playback : stream_playbacks) {
+		AudioServer::get_singleton()->set_playback_paused(playback, p_pause);
 	}
 }
 
 bool AudioStreamPlayer::get_stream_paused() const {
+	// There's currently no way to pause some playback streams but not others. Check the first and don't bother looking at the rest.
+	if (!stream_playbacks.is_empty()) {
+		return AudioServer::get_singleton()->is_playback_paused(stream_playbacks[0]);
+	}
+	return false;
+}
+
+Vector<AudioFrame> AudioStreamPlayer::_get_volume_vector() {
+	Vector<AudioFrame> volume_vector;
+	// We need at most four stereo pairs (for 7.1 systems).
+	volume_vector.resize(4);
 
-	return stream_paused;
+	// Initialize the volume vector to zero.
+	for (AudioFrame &channel_volume_db : volume_vector) {
+		channel_volume_db = AudioFrame(0, 0);
+	}
+
+	float volume_linear = Math::db2linear(volume_db);
+
+	// Set the volume vector up according to the speaker mode and mix target.
+	// TODO do we need to scale the volume down when we output to more channels?
+	if (AudioServer::get_singleton()->get_speaker_mode() == AudioServer::SPEAKER_MODE_STEREO) {
+		volume_vector.write[0] = AudioFrame(volume_linear, volume_linear);
+	} else {
+		switch (mix_target) {
+			case MIX_TARGET_STEREO: {
+				volume_vector.write[0] = AudioFrame(volume_linear, volume_linear);
+			} break;
+			case MIX_TARGET_SURROUND: {
+				// TODO Make sure this is right.
+				volume_vector.write[0] = AudioFrame(volume_linear, volume_linear);
+				volume_vector.write[1] = AudioFrame(volume_linear, /* LFE= */ 1.0f);
+				volume_vector.write[2] = AudioFrame(volume_linear, volume_linear);
+				volume_vector.write[3] = AudioFrame(volume_linear, volume_linear);
+			} break;
+			case MIX_TARGET_CENTER: {
+				// TODO Make sure this is right.
+				volume_vector.write[1] = AudioFrame(volume_linear, /* LFE= */ 1.0f);
+			} break;
+		}
+	}
+	return volume_vector;
 }
 
 void AudioStreamPlayer::_validate_property(PropertyInfo &property) const {
-
 	if (property.name == "bus") {
-
 		String options;
 		for (int i = 0; i < AudioServer::get_singleton()->get_bus_count(); i++) {
-			if (i > 0)
+			if (i > 0) {
 				options += ",";
+			}
 			String name = AudioServer::get_singleton()->get_bus_name(i);
 			options += name;
 		}
@@ -365,16 +295,17 @@ void AudioStreamPlayer::_validate_property(PropertyInfo &property) const {
 }
 
 void AudioStreamPlayer::_bus_layout_changed() {
-
-	_change_notify();
+	notify_property_list_changed();
 }
 
 Ref<AudioStreamPlayback> AudioStreamPlayer::get_stream_playback() {
-	return stream_playback;
+	if (!stream_playbacks.is_empty()) {
+		return stream_playbacks[stream_playbacks.size() - 1];
+	}
+	return nullptr;
 }
 
 void AudioStreamPlayer::_bind_methods() {
-
 	ClassDB::bind_method(D_METHOD("set_stream", "stream"), &AudioStreamPlayer::set_stream);
 	ClassDB::bind_method(D_METHOD("get_stream"), &AudioStreamPlayer::get_stream);
 
@@ -406,6 +337,9 @@ void AudioStreamPlayer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_stream_paused", "pause"), &AudioStreamPlayer::set_stream_paused);
 	ClassDB::bind_method(D_METHOD("get_stream_paused"), &AudioStreamPlayer::get_stream_paused);
 
+	ClassDB::bind_method(D_METHOD("set_max_polyphony", "max_polyphony"), &AudioStreamPlayer::set_max_polyphony);
+	ClassDB::bind_method(D_METHOD("get_max_polyphony"), &AudioStreamPlayer::get_max_polyphony);
+
 	ClassDB::bind_method(D_METHOD("get_stream_playback"), &AudioStreamPlayer::get_stream_playback);
 
 	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "stream", PROPERTY_HINT_RESOURCE_TYPE, "AudioStream"), "set_stream", "get_stream");
@@ -415,6 +349,7 @@ void AudioStreamPlayer::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "autoplay"), "set_autoplay", "is_autoplay_enabled");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "stream_paused", PROPERTY_HINT_NONE, ""), "set_stream_paused", "get_stream_paused");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "mix_target", PROPERTY_HINT_ENUM, "Stereo,Surround,Center"), "set_mix_target", "get_mix_target");
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "max_polyphony", PROPERTY_HINT_NONE, ""), "set_max_polyphony", "get_max_polyphony");
 	ADD_PROPERTY(PropertyInfo(Variant::STRING_NAME, "bus", PROPERTY_HINT_ENUM, ""), "set_bus", "get_bus");
 
 	ADD_SIGNAL(MethodInfo("finished"));
@@ -425,20 +360,6 @@ void AudioStreamPlayer::_bind_methods() {
 }
 
 AudioStreamPlayer::AudioStreamPlayer() {
-
-	mix_volume_db = 0;
-	pitch_scale = 1.0;
-	volume_db = 0;
-	autoplay = false;
-	setseek = -1;
-	active = false;
-	stream_paused = false;
-	stream_paused_fade = false;
-	mix_target = MIX_TARGET_STEREO;
-	fadeout_buffer.resize(512);
-	setstop = false;
-	use_fadeout = false;
-
 	AudioServer::get_singleton()->connect("bus_layout_changed", callable_mp(this, &AudioStreamPlayer::_bus_layout_changed));
 }