Move mix_rate, ouput_latency to AudioDriverManager

Each driver used to define the (same) project settings values
`audio/mix_rate` and `audio/output_latency`, but the setting names are
not driver specific.
Overriding is still possible via platform tags.

drivers/alsa/audio_driver_alsa.cpp

@@ -38,7 +38,7 @@
 #include <errno.h>
 
 Error AudioDriverALSA::init_device() {
-	mix_rate = GLOBAL_DEF("audio/mix_rate", DEFAULT_MIX_RATE);
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 	speaker_mode = SPEAKER_MODE_STEREO;
 	channels = 2;
 
@@ -104,7 +104,7 @@ Error AudioDriverALSA::init_device() {
 	// In ALSA the period size seems to be the one that will determine the actual latency
 	// Ref: https://www.alsa-project.org/main/index.php/FramesPeriods
 	unsigned int periods = 2;
-	int latency = GLOBAL_DEF("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+	int latency = GLOBAL_GET("audio/output_latency");
 	buffer_frames = closest_power_of_2(latency * mix_rate / 1000);
 	buffer_size = buffer_frames * periods;
 	period_size = buffer_frames;

drivers/coreaudio/audio_driver_coreaudio.cpp

@@ -116,7 +116,7 @@ Error AudioDriverCoreAudio::init() {
 			break;
 	}
 
-	mix_rate = GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 
 	zeromem(&strdesc, sizeof(strdesc));
 	strdesc.mFormatID = kAudioFormatLinearPCM;
@@ -131,7 +131,7 @@ Error AudioDriverCoreAudio::init() {
 	result = AudioUnitSetProperty(audio_unit, kAudioUnitProperty_StreamFormat, kAudioUnitScope_Input, kOutputBus, &strdesc, sizeof(strdesc));
 	ERR_FAIL_COND_V(result != noErr, FAILED);
 
-	int latency = GLOBAL_DEF_RST("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+	int latency = GLOBAL_GET("audio/output_latency");
 	// Sample rate is independent of channels (ref: https://stackoverflow.com/questions/11048825/audio-sample-frequency-rely-on-channels)
 	buffer_frames = closest_power_of_2(latency * mix_rate / 1000);
 
@@ -403,7 +403,7 @@ Error AudioDriverCoreAudio::capture_init() {
 			break;
 	}
 
-	mix_rate = GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 
 	zeromem(&strdesc, sizeof(strdesc));
 	strdesc.mFormatID = kAudioFormatLinearPCM;

drivers/pulseaudio/audio_driver_pulseaudio.cpp

@@ -179,7 +179,7 @@ Error AudioDriverPulseAudio::init_device() {
 			break;
 	}
 
-	int latency = GLOBAL_DEF_RST("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+	int latency = GLOBAL_GET("audio/output_latency");
 	buffer_frames = closest_power_of_2(latency * mix_rate / 1000);
 	pa_buffer_size = buffer_frames * pa_map.channels;
 
@@ -237,7 +237,7 @@ Error AudioDriverPulseAudio::init() {
 	thread_exited = false;
 	exit_thread = false;
 
-	mix_rate = GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 
 	pa_ml = pa_mainloop_new();
 	ERR_FAIL_COND_V(pa_ml == nullptr, ERR_CANT_OPEN);

drivers/wasapi/audio_driver_wasapi.cpp

@@ -387,7 +387,7 @@ Error AudioDriverWASAPI::finish_capture_device() {
 }
 
 Error AudioDriverWASAPI::init() {
-	mix_rate = GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 
 	Error err = init_render_device();
 	if (err != OK) {

drivers/xaudio2/audio_driver_xaudio2.cpp

@@ -44,12 +44,12 @@ Error AudioDriverXAudio2::init() {
 	pcm_open = false;
 	samples_in = nullptr;
 
-	mix_rate = GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 	// FIXME: speaker_mode seems unused in the Xaudio2 driver so far
 	speaker_mode = SPEAKER_MODE_STEREO;
 	channels = 2;
 
-	int latency = GLOBAL_DEF_RST("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+	int latency = GLOBAL_GET("audio/output_latency");
 	buffer_size = closest_power_of_2(latency * mix_rate / 1000);
 
 	samples_in = memnew_arr(int32_t, buffer_size * channels);

platform/android/audio_driver_jandroid.cpp

@@ -73,9 +73,9 @@ Error AudioDriverAndroid::init() {
 	//        __android_log_print(ANDROID_LOG_VERBOSE, "SDL", "SDL audio: opening device");
 
 	JNIEnv *env = ThreadAndroid::get_env();
-	int mix_rate = GLOBAL_DEF_RST("audio/mix_rate", 44100);
+	int mix_rate = GLOBAL_GET("audio/mix_rate");
 
-	int latency = GLOBAL_DEF_RST("audio/output_latency", 25);
+	int latency = GLOBAL_GET("audio/output_latency");
 	unsigned int buffer_size = next_power_of_2(latency * mix_rate / 1000);
 	print_verbose("Audio buffer size: " + itos(buffer_size));
 

platform/haiku/audio_driver_media_kit.cpp

@@ -39,11 +39,11 @@ int32_t *AudioDriverMediaKit::samples_in = nullptr;
 Error AudioDriverMediaKit::init() {
 	active = false;
 
-	mix_rate = GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 	speaker_mode = SPEAKER_MODE_STEREO;
 	channels = 2;
 
-	int latency = GLOBAL_DEF_RST("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+	int latency = GLOBAL_GET("audio/output_latency");
 	buffer_size = next_power_of_2(latency * mix_rate / 1000);
 	samples_in = memnew_arr(int32_t, buffer_size * channels);
 

platform/javascript/audio_driver_javascript.cpp

@@ -64,8 +64,8 @@ void AudioDriverJavaScript::process_capture(float sample) {
 }
 
 Error AudioDriverJavaScript::init() {
-	int mix_rate = GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
-	int latency = GLOBAL_DEF_RST("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+	int mix_rate = GLOBAL_GET("audio/mix_rate");
+	int latency = GLOBAL_GET("audio/output_latency");
 
 	/* clang-format off */
 	_driver_id = EM_ASM_INT({

servers/audio/audio_driver_dummy.cpp

@@ -39,11 +39,11 @@ Error AudioDriverDummy::init() {
 	exit_thread = false;
 	samples_in = nullptr;
 
-	mix_rate = DEFAULT_MIX_RATE;
+	mix_rate = GLOBAL_GET("audio/mix_rate");
 	speaker_mode = SPEAKER_MODE_STEREO;
 	channels = 2;
 
-	int latency = GLOBAL_DEF_RST("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+	int latency = GLOBAL_GET("audio/output_latency");
 	buffer_frames = closest_power_of_2(latency * mix_rate / 1000);
 
 	samples_in = memnew_arr(int32_t, buffer_frames * channels);

servers/audio_server.cpp

@@ -182,6 +182,9 @@ int AudioDriverManager::get_driver_count() {
 
 void AudioDriverManager::initialize(int p_driver) {
 	GLOBAL_DEF_RST("audio/enable_audio_input", false);
+	GLOBAL_DEF_RST("audio/mix_rate", DEFAULT_MIX_RATE);
+	GLOBAL_DEF_RST("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
+
 	int failed_driver = -1;
 
 	// Check if there is a selected driver

servers/audio_server.h

@@ -80,9 +80,6 @@ public:
 		SPEAKER_SURROUND_71,
 	};
 
-	static const int DEFAULT_MIX_RATE = 44100;
-	static const int DEFAULT_OUTPUT_LATENCY = 15;
-
 	static AudioDriver *get_singleton();
 	void set_singleton();
 
@@ -129,6 +126,9 @@ class AudioDriverManager {
 		MAX_DRIVERS = 10
 	};
 
+	static const int DEFAULT_MIX_RATE = 44100;
+	static const int DEFAULT_OUTPUT_LATENCY = 15;
+
 	static AudioDriver *drivers[MAX_DRIVERS];
 	static int driver_count;