1 files changed, 113 insertions, 64 deletions

diff --git a/platform/javascript/audio_driver_javascript.cpp b/platform/javascript/audio_driver_javascript.cpp
index f1bc7c4382..9604914b2c 100644
--- a/platform/javascript/audio_driver_javascript.cpp
+++ b/platform/javascript/audio_driver_javascript.cpp
@@ -30,27 +30,34 @@
 
 #include "audio_driver_javascript.h"
 
+#include "core/project_settings.h"
+
 #include <emscripten.h>
 
-AudioDriverJavaScript *AudioDriverJavaScript::singleton = NULL;
+AudioDriverJavaScript *AudioDriverJavaScript::singleton = nullptr;
 
-const char *AudioDriverJavaScript::get_name() const {
+bool AudioDriverJavaScript::is_available() {
+	return EM_ASM_INT({
+		if (!(window.AudioContext || window.webkitAudioContext)) {
+			return 0;
+		}
+		return 1;
+	}) != 0;
+}
 
+const char *AudioDriverJavaScript::get_name() const {
 	return "JavaScript";
 }
 
 extern "C" EMSCRIPTEN_KEEPALIVE void audio_driver_js_mix() {
-
 	AudioDriverJavaScript::singleton->mix_to_js();
 }
 
 extern "C" EMSCRIPTEN_KEEPALIVE void audio_driver_process_capture(float sample) {
-
 	AudioDriverJavaScript::singleton->process_capture(sample);
 }
 
 void AudioDriverJavaScript::mix_to_js() {
-
 	int channel_count = get_total_channels_by_speaker_mode(get_speaker_mode());
 	int sample_count = memarr_len(internal_buffer) / channel_count;
 	int32_t *stream_buffer = reinterpret_cast<int32_t *>(internal_buffer);
@@ -61,39 +68,41 @@ void AudioDriverJavaScript::mix_to_js() {
 }
 
 void AudioDriverJavaScript::process_capture(float sample) {
-
 	int32_t sample32 = int32_t(sample * 32768.f) * (1U << 16);
 	input_buffer_write(sample32);
 }
 
 Error AudioDriverJavaScript::init() {
+	int mix_rate = GLOBAL_GET("audio/mix_rate");
+	int latency = GLOBAL_GET("audio/output_latency");
 
 	/* clang-format off */
-	EM_ASM({
-		_audioDriver_audioContext = new (window.AudioContext || window.webkitAudioContext);
-		_audioDriver_audioInput = null;
-		_audioDriver_inputStream = null;
-		_audioDriver_scriptNode = null;
-	});
+	_driver_id = EM_ASM_INT({
+		const MIX_RATE = $0;
+		const LATENCY = $1 / 1000;
+		return Module.IDHandler.add({
+			'context': new (window.AudioContext || window.webkitAudioContext)({ sampleRate: MIX_RATE, latencyHint: LATENCY}),
+			'input': null,
+			'stream': null,
+			'script': null
+		});
+	}, mix_rate, latency);
 	/* clang-format on */
 
 	int channel_count = get_total_channels_by_speaker_mode(get_speaker_mode());
+	buffer_length = closest_power_of_2((latency * mix_rate / 1000) * channel_count);
 	/* clang-format off */
 	buffer_length = EM_ASM_INT({
-		var CHANNEL_COUNT = $0;
-
-		var channelCount = _audioDriver_audioContext.destination.channelCount;
-		try {
-			// Try letting the browser recommend a buffer length.
-			_audioDriver_scriptNode = _audioDriver_audioContext.createScriptProcessor(0, 2, channelCount);
-		} catch (e) {
-			// ...otherwise, default to 4096.
-			_audioDriver_scriptNode = _audioDriver_audioContext.createScriptProcessor(4096, 2, channelCount);
-		}
-		_audioDriver_scriptNode.connect(_audioDriver_audioContext.destination);
-
-		return _audioDriver_scriptNode.bufferSize;
-	}, channel_count);
+		var ref = Module.IDHandler.get($0);
+		const ctx = ref['context'];
+		const BUFFER_LENGTH = $1;
+		const CHANNEL_COUNT = $2;
+
+		var script = ctx.createScriptProcessor(BUFFER_LENGTH, 2, CHANNEL_COUNT);
+		script.connect(ctx.destination);
+		ref['script'] = script;
+		return script.bufferSize;
+	}, _driver_id, buffer_length, channel_count);
 	/* clang-format on */
 	if (!buffer_length) {
 		return FAILED;
@@ -109,14 +118,14 @@ Error AudioDriverJavaScript::init() {
 }
 
 void AudioDriverJavaScript::start() {
-
 	/* clang-format off */
 	EM_ASM({
-		var INTERNAL_BUFFER_PTR = $0;
+		const ref = Module.IDHandler.get($0);
+		var INTERNAL_BUFFER_PTR = $1;
 
 		var audioDriverMixFunction = cwrap('audio_driver_js_mix');
 		var audioDriverProcessCapture = cwrap('audio_driver_process_capture', null, ['number']);
-		_audioDriver_scriptNode.onaudioprocess = function(audioProcessingEvent) {
+		ref['script'].onaudioprocess = function(audioProcessingEvent) {
 			audioDriverMixFunction();
 
 			var input = audioProcessingEvent.inputBuffer;
@@ -133,7 +142,7 @@ void AudioDriverJavaScript::start() {
 				}
 			}
 
-			if (_audioDriver_audioInput) {
+			if (ref['input']) {
 				var inputDataL = input.getChannelData(0);
 				var inputDataR = input.getChannelData(1);
 				for (var i = 0; i < inputDataL.length; i++) {
@@ -142,34 +151,54 @@ void AudioDriverJavaScript::start() {
 				}
 			}
 		};
-	}, internal_buffer);
+	}, _driver_id, internal_buffer);
 	/* clang-format on */
 }
 
 void AudioDriverJavaScript::resume() {
 	/* clang-format off */
 	EM_ASM({
-		if (_audioDriver_audioContext.resume)
-			_audioDriver_audioContext.resume();
-	});
+		const ref = Module.IDHandler.get($0);
+		if (ref && ref['context'] && ref['context'].resume)
+			ref['context'].resume();
+	}, _driver_id);
 	/* clang-format on */
 }
 
-int AudioDriverJavaScript::get_mix_rate() const {
+float AudioDriverJavaScript::get_latency() {
+	/* clang-format off */
+	return EM_ASM_DOUBLE({
+		const ref = Module.IDHandler.get($0);
+		var latency = 0;
+		if (ref && ref['context']) {
+			const ctx = ref['context'];
+			if (ctx.baseLatency) {
+				latency += ctx.baseLatency;
+			}
+			if (ctx.outputLatency) {
+				latency += ctx.outputLatency;
+			}
+		}
+		return latency;
+	}, _driver_id);
+	/* clang-format on */
+}
 
+int AudioDriverJavaScript::get_mix_rate() const {
 	/* clang-format off */
-	return EM_ASM_INT_V({
-		return _audioDriver_audioContext.sampleRate;
-	});
+	return EM_ASM_INT({
+		const ref = Module.IDHandler.get($0);
+		return ref && ref['context'] ? ref['context'].sampleRate : 0;
+	}, _driver_id);
 	/* clang-format on */
 }
 
 AudioDriver::SpeakerMode AudioDriverJavaScript::get_speaker_mode() const {
-
 	/* clang-format off */
-	return get_speaker_mode_by_total_channels(EM_ASM_INT_V({
-		return _audioDriver_audioContext.destination.channelCount;
-	}));
+	return get_speaker_mode_by_total_channels(EM_ASM_INT({
+		const ref = Module.IDHandler.get($0);
+		return ref && ref['context'] ? ref['context'].destination.channelCount : 0;
+	}, _driver_id));
 	/* clang-format on */
 }
 
@@ -180,32 +209,55 @@ void AudioDriverJavaScript::lock() {
 void AudioDriverJavaScript::unlock() {
 }
 
-void AudioDriverJavaScript::finish() {
+void AudioDriverJavaScript::finish_async() {
+	// Close the context, add the operation to the async_finish list in module.
+	int id = _driver_id;
+	_driver_id = 0;
 
 	/* clang-format off */
 	EM_ASM({
-		_audioDriver_audioContext = null;
-		_audioDriver_audioInput = null;
-		_audioDriver_scriptNode = null;
-	});
+		const id = $0;
+		var ref = Module.IDHandler.get(id);
+		Module.async_finish.push(new Promise(function(accept, reject) {
+			if (!ref) {
+				console.log("Ref not found!", id, Module.IDHandler);
+				setTimeout(accept, 0);
+			} else {
+				Module.IDHandler.remove(id);
+				const context = ref['context'];
+				// Disconnect script and input.
+				ref['script'].disconnect();
+				if (ref['input'])
+					ref['input'].disconnect();
+				ref = null;
+				context.close().then(function() {
+					accept();
+				}).catch(function(e) {
+					accept();
+				});
+			}
+		}));
+	}, id);
 	/* clang-format on */
+}
 
+void AudioDriverJavaScript::finish() {
 	if (internal_buffer) {
 		memdelete_arr(internal_buffer);
-		internal_buffer = NULL;
+		internal_buffer = nullptr;
 	}
 }
 
 Error AudioDriverJavaScript::capture_start() {
-
 	input_buffer_init(buffer_length);
 
 	/* clang-format off */
 	EM_ASM({
 		function gotMediaInput(stream) {
-			_audioDriver_inputStream = stream;
-			_audioDriver_audioInput = _audioDriver_audioContext.createMediaStreamSource(stream);
-			_audioDriver_audioInput.connect(_audioDriver_scriptNode);
+			var ref = Module.IDHandler.get($0);
+			ref['stream'] = stream;
+			ref['input'] = ref['context'].createMediaStreamSource(stream);
+			ref['input'].connect(ref['script']);
 		}
 
 		function gotMediaInputError(e) {
@@ -219,30 +271,30 @@ Error AudioDriverJavaScript::capture_start() {
 				navigator.getUserMedia = navigator.webkitGetUserMedia || navigator.mozGetUserMedia;
 			navigator.getUserMedia({"audio": true}, gotMediaInput, gotMediaInputError);
 		}
-	});
+	}, _driver_id);
 	/* clang-format on */
 
 	return OK;
 }
 
 Error AudioDriverJavaScript::capture_stop() {
-
 	/* clang-format off */
 	EM_ASM({
-		if (_audioDriver_inputStream) {
-			const tracks = _audioDriver_inputStream.getTracks();
+		var ref = Module.IDHandler.get($0);
+		if (ref['stream']) {
+			const tracks = ref['stream'].getTracks();
 			for (var i = 0; i < tracks.length; i++) {
 				tracks[i].stop();
 			}
-			_audioDriver_inputStream = null;
+			ref['stream'] = null;
 		}
 
-		if (_audioDriver_audioInput) {
-			_audioDriver_audioInput.disconnect();
-			_audioDriver_audioInput = null;
+		if (ref['input']) {
+			ref['input'].disconnect();
+			ref['input'] = null;
 		}
 
-	});
+	}, _driver_id);
 	/* clang-format on */
 
 	input_buffer.clear();
@@ -251,8 +303,5 @@ Error AudioDriverJavaScript::capture_stop() {
 }
 
 AudioDriverJavaScript::AudioDriverJavaScript() {
-
-	internal_buffer = NULL;
-
 	singleton = this;
 }