Add grouping to AudioInterface

README.md

@@ -1,19 +1,19 @@
 # Rack
 
-*Rack* is the engine for the VCV open-source virtual Eurorack DAW.
+*Rack* is the engine for the VCV open-source virtual modular synthesizer.
 
 ![Rack screenshot](https://vcvrack.com/images/screenshot.png)
 
 This README includes instructions for building Rack from source. For information about the software, go to https://vcvrack.com/.
 
-## The [Issue Tracker](https://github.com/VCVRack/Rack/issues) *is* the official developer's forum
+## The [Issue Tracker](https://github.com/VCVRack/Rack/issues?q=is%3Aissue+is%3Aopen+sort%3Aupdated-desc) *is* the official developer's forum
 
 Bug reports, feature requests, and even *questions/discussions* are welcome on the GitHub Issue Tracker for all VCVRack repos.
 However, please search before posting to avoid duplicates, and limit to one issue per post.
 
-You may vote on feature requests by using the Thumbs Up/Down reaction on the first post.
+Please vote on feature requests by using the Thumbs Up/Down reaction on the first post.
 
-I rarely accept Pull Requests, so please notify me in advance to plan your contribution before writing code.
+I rarely accept code contributions to Rack itself, so please notify me in advance if you wish to send a pull request.
 
 ## Setting up your development environment
 
@@ -33,14 +33,16 @@ Install build dependencies with the pacman package manger.
 
 ### Linux
 
-With your distro's package manager, make sure you have installed `git`, `gcc`, `make`, `cmake`, `tar`, and `unzip`.
+With your distro's package manager, make sure you have installed `git`, `gcc`, `make`, `cmake`, `tar`, `unzip`, and `curl`.
 
 ## Building
 
 *If the build fails for you, please report the issue with a detailed error message to help the portability of Rack.*
 
 Clone this repository with `git clone https://github.com/VCVRack/Rack.git` and `cd Rack`.
-If you would like to build a previous version of Rack instead of the master branch, check out the desired tag with `git checkout v0.4.0` for example.
+
+The `master` branch contains the latest public code and breaks its plugin [API](https://en.wikipedia.org/wiki/Application_programming_interface) and [ABI](https://en.wikipedia.org/wiki/Application_binary_interface) frequently.
+If you wish to build a previous version of Rack which is API/ABI-compatible with an official Rack release, check out the desired branch with `git checkout v0.5` for example.
 
 Clone submodules.
 
@@ -51,7 +53,7 @@ You may use make's `-j$(nproc)` flag to parallelize builds across all your CPU c
 
 	make dep
 
-You may use `make dep RTAUDIO_ALL_APIS=1` to attempt to build with all audio driver APIs enabled for your operating system.
+You may use `make dep RTAUDIO_ALL_APIS=1` to attempt to build with all audio driver APIs enabled for your operating system, although this is unsupported.
 
 You should see a message that all dependencies built successfully.
 

include/audio.hpp

@@ -12,12 +12,10 @@ namespace rack {
 
 
 struct AudioIO {
-	int maxOutputs = 8;
-	int maxInputs = 8;
-
 	// Stream properties
 	int driver = 0;
 	int device = -1;
+	int offset = 0;
 	int sampleRate = 44100;
 	int blockSize = 256;
 	int numOutputs = 0;
@@ -34,8 +32,16 @@ struct AudioIO {
 	void setDriver(int driver);
 
 	int getDeviceCount();
+	bool getDeviceInfo(int device, RtAudio::DeviceInfo *deviceInfo);
+	int getDeviceMaxChannels(int device);
 	std::string getDeviceName(int device);
-	std::string getDeviceDetail(int device);
+	std::string getDeviceDetail(int device, int offset, int maxChannels);
+	void setDevice(int device, int offset, int maxChannels);
+
+	void setSampleRate(int sampleRate);
+	void setBlockSize(int blockSize);
+
+	/** Must close the stream before opening */
 	void openStream();
 	void closeStream();
 	/** Returns whether the audio stream is open and running */

src/app/AudioWidget.cpp

@@ -36,14 +36,17 @@ struct AudioDriverChoice : LedDisplayChoice {
 struct AudioDeviceItem : MenuItem {
 	AudioIO *audioIO;
 	int device;
+	int offset;
+	int maxChannels;
 	void onAction(EventAction &e) override {
-		audioIO->device = device;
-		audioIO->openStream();
+		audioIO->setDevice(device, offset, maxChannels);
 	}
 };
 
 struct AudioDeviceChoice : LedDisplayChoice {
 	AudioWidget *audioWidget;
+	int groupChannels = 8;
+	int maxTotalChannels = 64;
 	void onAction(EventAction &e) override {
 		Menu *menu = gScene->createMenu();
 		menu->addChild(construct<MenuLabel>(&MenuLabel::text, "Audio device"));
@@ -57,16 +60,21 @@ struct AudioDeviceChoice : LedDisplayChoice {
 			menu->addChild(item);
 		}
 		for (int device = 0; device < deviceCount; device++) {
-			AudioDeviceItem *item = new AudioDeviceItem();
-			item->audioIO = audioWidget->audioIO;
-			item->device = device;
-			item->text = audioWidget->audioIO->getDeviceDetail(device);
-			item->rightText = CHECKMARK(item->device == audioWidget->audioIO->device);
-			menu->addChild(item);
+			int maxChannels = min(maxTotalChannels, audioWidget->audioIO->getDeviceMaxChannels(device));
+			for (int offset = 0; offset < maxChannels; offset += groupChannels) {
+				AudioDeviceItem *item = new AudioDeviceItem();
+				item->audioIO = audioWidget->audioIO;
+				item->device = device;
+				item->offset = offset;
+				item->maxChannels = groupChannels;
+				item->text = audioWidget->audioIO->getDeviceDetail(device, offset, groupChannels);
+				item->rightText = CHECKMARK(item->device == audioWidget->audioIO->device && item->offset == audioWidget->audioIO->offset);
+				menu->addChild(item);
+			}
 		}
 	}
 	void step() override {
-		text = audioWidget->audioIO->getDeviceDetail(audioWidget->audioIO->device);
+		text = audioWidget->audioIO->getDeviceDetail(audioWidget->audioIO->device, audioWidget->audioIO->offset, groupChannels);
 		if (text.empty()) {
 			text = "(No device)";
 			color.a = 0.5f;
@@ -83,8 +91,7 @@ struct AudioSampleRateItem : MenuItem {
 	AudioIO *audioIO;
 	int sampleRate;
 	void onAction(EventAction &e) override {
-		audioIO->sampleRate = sampleRate;
-		audioIO->openStream();
+		audioIO->setSampleRate(sampleRate);
 	}
 };
 
@@ -112,8 +119,7 @@ struct AudioBlockSizeItem : MenuItem {
 	AudioIO *audioIO;
 	int blockSize;
 	void onAction(EventAction &e) override {
-		audioIO->blockSize = blockSize;
-		audioIO->openStream();
+		audioIO->setBlockSize(blockSize);
 	}
 };
 

src/audio.cpp

@@ -75,54 +75,107 @@ int AudioIO::getDeviceCount() {
 	return 0;
 }
 
+bool AudioIO::getDeviceInfo(int device, RtAudio::DeviceInfo *deviceInfo) {
+	if (!deviceInfo)
+		return false;
+
+	if (rtAudio) {
+		if (device == this->device) {
+			*deviceInfo = this->deviceInfo;
+			return true;
+		}
+		else {
+			try {
+				*deviceInfo = rtAudio->getDeviceInfo(device);
+				return true;
+			}
+			catch (RtAudioError &e) {
+				warn("Failed to query RtAudio device: %s", e.what());
+				return false;
+			}
+		}
+	}
+	else {
+		return false;
+	}
+}
+
+int AudioIO::getDeviceMaxChannels(int device) {
+	if (device < 0)
+		return 0;
+
+	if (rtAudio) {
+		RtAudio::DeviceInfo deviceInfo;
+		if (getDeviceInfo(device, &deviceInfo))
+			return max(deviceInfo.inputChannels, deviceInfo.outputChannels);
+	}
+	if (driver == BRIDGE_DRIVER) {
+		return 2;
+	}
+	return 0;
+}
+
 std::string AudioIO::getDeviceName(int device) {
 	if (device < 0)
 		return "";
 
 	if (rtAudio) {
-		try {
-			RtAudio::DeviceInfo deviceInfo;
-			if (device == this->device)
-				deviceInfo = this->deviceInfo;
-			else
-				deviceInfo = rtAudio->getDeviceInfo(device);
+		RtAudio::DeviceInfo deviceInfo;
+		if (getDeviceInfo(device, &deviceInfo))
 			return deviceInfo.name;
-		}
-		catch (RtAudioError &e) {
-			warn("Failed to query RtAudio device: %s", e.what());
-		}
 	}
 	if (driver == BRIDGE_DRIVER) {
-		if (device >= 0)
-			return stringf("%d", device + 1);
+		return stringf("%d", device + 1);
 	}
 	return "";
 }
 
-std::string AudioIO::getDeviceDetail(int device) {
+std::string AudioIO::getDeviceDetail(int device, int offset, int maxChannels) {
 	if (device < 0)
 		return "";
 
 	if (rtAudio) {
-		try {
-			RtAudio::DeviceInfo deviceInfo;
-			if (device == this->device)
-				deviceInfo = this->deviceInfo;
-			else
-				deviceInfo = rtAudio->getDeviceInfo(device);
-			return stringf("%s (%d in, %d out)", deviceInfo.name.c_str(), deviceInfo.inputChannels, deviceInfo.outputChannels);
-		}
-		catch (RtAudioError &e) {
-			warn("Failed to query RtAudio device: %s", e.what());
+		RtAudio::DeviceInfo deviceInfo;
+		if (getDeviceInfo(device, &deviceInfo)) {
+			std::string deviceDetail = stringf("%s (", deviceInfo.name.c_str());
+			if (offset < (int) deviceInfo.inputChannels)
+				deviceDetail += stringf("%d-%d in", offset + 1, min(offset + maxChannels, deviceInfo.inputChannels));
+			if (offset < (int) deviceInfo.inputChannels && offset < (int) deviceInfo.outputChannels)
+				deviceDetail += ", ";
+			if (offset < (int) deviceInfo.outputChannels)
+				deviceDetail += stringf("%d-%d out", offset + 1, min(offset + maxChannels, deviceInfo.outputChannels));
+			deviceDetail += ")";
+			return deviceDetail;
 		}
 	}
 	if (driver == BRIDGE_DRIVER) {
-		if (device >= 0)
-			return stringf("Channel %d", device + 1);
+		return stringf("Channel %d", device + 1);
 	}
 	return "";
 }
 
+void AudioIO::setDevice(int device, int offset, int maxChannels) {
+	closeStream();
+	this->device = device;
+	this->offset = offset;
+	this->numOutputs = maxChannels;
+	this->numInputs = maxChannels;
+	openStream();
+}
+
+void AudioIO::setSampleRate(int sampleRate) {
+	closeStream();
+	this->sampleRate = sampleRate;
+	openStream();
+}
+
+void AudioIO::setBlockSize(int blockSize) {
+	closeStream();
+	this->blockSize = blockSize;
+	openStream();
+}
+
+
 static int rtCallback(void *outputBuffer, void *inputBuffer, unsigned int nFrames, double streamTime, RtAudioStreamStatus status, void *userData) {
 	AudioIO *audioIO = (AudioIO*) userData;
 	assert(audioIO);
@@ -131,10 +184,6 @@ static int rtCallback(void *outputBuffer, void *inputBuffer, unsigned int nFrame
 }
 
 void AudioIO::openStream() {
-	// Close device but remember the current device number
-	int device = this->device;
-	closeStream();
-
 	if (device < 0)
 		return;
 
@@ -148,8 +197,11 @@ void AudioIO::openStream() {
 			return;
 		}
 
-		numOutputs = min(deviceInfo.outputChannels, maxOutputs);
-		numInputs = min(deviceInfo.inputChannels, maxInputs);
+		if (rtAudio->isStreamOpen())
+			return;
+
+		numOutputs = clamp((int) deviceInfo.outputChannels - offset, 0, numOutputs);
+		numInputs = clamp((int) deviceInfo.inputChannels - offset, 0, numInputs);
 
 		if (numOutputs == 0 && numInputs == 0) {
 			warn("RtAudio device %d has 0 inputs and 0 outputs");
@@ -159,10 +211,12 @@ void AudioIO::openStream() {
 		RtAudio::StreamParameters outParameters;
 		outParameters.deviceId = device;
 		outParameters.nChannels = numOutputs;
+		outParameters.firstChannel = offset;
 
 		RtAudio::StreamParameters inParameters;
 		inParameters.deviceId = device;
 		inParameters.nChannels = numInputs;
+		inParameters.firstChannel = offset;
 
 		RtAudio::StreamOptions options;
 		// options.flags |= RTAUDIO_SCHEDULE_REALTIME;
@@ -175,11 +229,12 @@ void AudioIO::openStream() {
 		}
 
 		try {
-			debug("Opening audio RtAudio device %d", device);
+			debug("Opening audio RtAudio device %d with %d in %d out", device, numInputs, numOutputs);
 			rtAudio->openStream(
 				numOutputs == 0 ? NULL : &outParameters,
 				numInputs == 0 ? NULL : &inParameters,
-				RTAUDIO_FLOAT32, closestSampleRate, (unsigned int*) &blockSize, &rtCallback, this, &options, NULL);
+				RTAUDIO_FLOAT32, closestSampleRate, (unsigned int*) &blockSize,
+				&rtCallback, this, &options, NULL);
 		}
 		catch (RtAudioError &e) {
 			warn("Failed to open RtAudio stream: %s", e.what());
@@ -197,12 +252,11 @@ void AudioIO::openStream() {
 
 		// Update sample rate because this may have changed
 		this->sampleRate = rtAudio->getStreamSampleRate();
-		this->device = device;
 		onOpenStream();
 	}
 	if (driver == BRIDGE_DRIVER) {
 		if (device < BRIDGE_CHANNELS) {
-			this->device = device;
+			// TODO
 		}
 	}
 }
@@ -230,10 +284,6 @@ void AudioIO::closeStream() {
 		deviceInfo = RtAudio::DeviceInfo();
 	}
 
-	// Reset rtAudio settings
-	device = -1;
-	numOutputs = 0;
-	numInputs = 0;
 	onCloseStream();
 }
 
@@ -274,6 +324,8 @@ json_t *AudioIO::toJson() {
 }
 
 void AudioIO::fromJson(json_t *rootJ) {
+	closeStream();
+
 	json_t *driverJ = json_object_get(rootJ, "driver");
 	if (driverJ)
 		setDriver(json_number_value(driverJ));

src/core/AudioInterface.cpp

@@ -35,11 +35,10 @@ struct AudioInterfaceIO : AudioIO {
 	DoubleRingBuffer<Frame<OUTPUTS>, (1<<15)> outputBuffer;
 
 	AudioInterfaceIO() {
-		maxOutputs = OUTPUTS;
-		maxInputs = INPUTS;
 	}
 
 	~AudioInterfaceIO() {
+		// Close stream here before destructing AudioInterfaceIO, so the mutexes are still valid when waiting to close.
 		closeStream();
 	}