Bela: libpd + EVO time-of-flight sensor, implemented in C++

_main.pd

#N canvas 0 22 450 300 12;
#X obj 37 37 r evo;
#X obj 78 119 timer;
#X obj 26 83 t f b;
#X obj 25 148 pack f f;
#X obj 24 177 print evo;
#X connect 0 0 2 0;
#X connect 1 0 3 1;
#X connect 2 0 3 0;
#X connect 2 1 1 1;
#X connect 3 0 4 0;

Evo.h

#include <I2c.h>

class Evo : public I2c
{
public:
	int readI2C() override {
		i2c_char_t c = 0;
		if(write(i2C_file, &c, sizeof(c)) != sizeof(c))
		{
			// error, abort
			fprintf(stderr, "Error while writing\n");
			return -1;
		}
		usleep(500);
		i2c_char_t r[3];
		if(sizeof(r) != read(i2C_file, r, sizeof(r)))
		{
			// handle error
			fprintf(stderr, "Error while reading\n");
			return -1;
		}
		// the manual is not clear about whether the first byte is the MSB or LSB
		distance_ = r[0] << 8 | r[1]; // either this (MSB first)...
		// distance_ = r[1] << 8 | r[0]; // or this (LSB first)...
		return 0;
	}
	
	int getDistance()
	{
		return distance_;
	}
private:
	int distance_ = 0;
};

render.cpp

// Custom libpd render.cpp to use with EVO ultrasonic distance sensor.
// The modifications (marked by `#ifdef ENABLE_EVO`) have been taken from this example https://forum.bela.io/d/1629-longer-range-tof-distance-sensors-with-bela/6
// and applied on top of
// https://github.com/BelaPlatform/Bela/blob/970163ea2a1c69b364ce4c4e3b1b92c3a3fceb17/core/default_libpd_render.cpp
// Place this file in a Bela project alongside a `_main.pd` which contains:
// [r evo]
// |
// [print]
// EVO address, bus and other properties are set in the first `ENABLE_EVO` block
/*
 * Default render file for Bela projects running Pd patches
 * using libpd.
 */
#include <Bela.h>

#define ENABLE_EVO
#define BELA_LIBPD_GUI

#include <DigitalChannelManager.h>
#include <stdio.h>
#define PD_THREADED_IO
#include <libpd/z_libpd.h>
extern "C" {
#include <libpd/s_stuff.h>
};
#include <libraries/Midi/Midi.h>
#include <libraries/Scope/Scope.h>
#include <string>
#include <sstream>
#include <algorithm>

#define ENABLE_TRILL

#ifdef ENABLE_EVO
#include "Evo.h"
Evo gEvo;
int gEvoI2cBus = 1; // the I2c bus the sensor is connected to
int gEvoI2cAddress = 0x31; // "Primary Slave Address"
int gEvoReadSleepMs = 10; // how often to read from the Evo
int gEvoSendIntervalMs = 100; // how often to send Evo reading to Pd
const char gEvoReceiverName[] = "evo"; // the name of the corresponding Pd [receive ...] object
float gEvoValue; // the evoReadTask sets this and render() sends it to Pd

void evoReadTask(void*)
{
	while(!Bela_stopRequested())
	{
		if(gEvo.readI2C()) {
			fprintf(stderr, "Error reading. Stopping\n");
			Bela_requestStop();
			break;
		}
		gEvoValue = gEvo.getDistance();
		usleep(gEvoReadSleepMs * 1000);
	}
}
#endif // ENABLE_EVO

#if (defined(BELA_LIBPD_GUI) || defined(ENABLE_TRILL))
#include <libraries/Pipe/Pipe.h>
template <typename T>
int getIdxFromId(const char* id, std::vector<std::pair<std::string,T>>& db)
{
	for(unsigned int n = 0; n < db.size(); ++n)
	{
		if(0 == strcmp(id, db[n].first.c_str()))
			return n;
	}
	return -1;
}
#endif // BELA_LIBPD_GUI || ENABLE_TRILL

#ifdef ENABLE_TRILL
#include <tuple>
#include <libraries/Trill/Trill.h>
AuxiliaryTask gTrillTask;
Pipe gTrillPipe;

static std::vector<std::string> gTrillAcks;
static std::vector<std::pair<std::string,Trill*>> gTouchSensors;
// how often to read the cap sensors inputs.
float touchSensorSleepInterval = 0.007;

void readTouchSensors(void*)
{
	for(unsigned int n = 0; n < gTouchSensors.size(); ++n)
	{
		Trill& touchSensor = *gTouchSensors[n].second;
		int ret;
		const Trill::Device type = touchSensor.deviceType();
		if(Trill::NONE == type)
			ret = 1;
		else
			ret = touchSensor.readI2C();
		if(!ret)
		{
			gTrillPipe.writeNonRt(n);
		}
	}
}
#endif // ENABLE_TRILL

#ifdef BELA_LIBPD_GUI
#include <libraries/Gui/Gui.h>

Pipe gGuiPipe;
Gui gui;
struct bufferDescription
{
	std::string name;
	int id;
	int size;
};
static std::vector<struct bufferDescription> gGuiDataBuffers;
static std::vector<std::string> gGuiControlBuffers;
struct guiControlMessageHeader
{
	uint32_t size;
	uint32_t type;
	uint32_t id;
};

bool guiControlDataCallback(JSONObject& root, void* arg)
{
	int ret = true;
	for(unsigned int n = 0; n < gGuiControlBuffers.size(); ++n)
	{
		const auto& b = gGuiControlBuffers[n];
		std::wstring key = JSON::s2ws(b);
		if (root.end() != root.find(key))
		{
			JSONValue* found = root[key];
			struct guiControlMessageHeader header;
			header.id = n;
			char* array;
			if(found->IsString())
			{
				std::string value = JSON::ws2s(found->AsString());
				header.type = 's';
				header.size = value.size();
				array = (char*)alloca(header.size);
				memcpy(array, value.c_str(), header.size);
			} else if(found->IsNumber())
			{
				float value = found->AsNumber();
				header.type = 'f';
				header.size = sizeof(value);
				array = (char*)alloca(header.size);
				memcpy(array, &value, header.size);
			} else {
				continue;
			}
			// do two separate reads: the pipe is datagram-based
			// so it would be impossible to receive partial messages
			// at the other end
			gGuiPipe.writeNonRt(header);
			gGuiPipe.writeNonRt(&array[0], header.size);
			// we have successully parsed this message, so the
			// default parser shouldn't when we return
			// note: in practice there may be times when we'd want
			// to have the default parser handle this message
			// (e.g.: when an "event" field is also present), but
			// for now we ignore them
			ret = false;
			continue;
		}
	}
	return ret;
}

#endif // BELA_LIBPD_GUI
enum { minFirstDigitalChannel = 10 };
static unsigned int gAnalogChannelsInUse;
static unsigned int gDigitalChannelsInUse;
static unsigned int gScopeChannelsInUse = 4;
static unsigned int gLibpdBlockSize;
static unsigned int gChannelsInUse;
//static const unsigned int gFirstAudioChannel = 0;
static unsigned int gFirstAnalogInChannel;
static unsigned int gFirstAnalogOutChannel;
static unsigned int gFirstDigitalChannel;
static unsigned int gLibpdDigitalChannelOffset;
static unsigned int gFirstScopeChannel;

void Bela_userSettings(BelaInitSettings *settings)
{
	settings->uniformSampleRate = 1;
	settings->interleave = 0;
	settings->analogOutputsPersist = 0;
}

float* gInBuf;
float* gOutBuf;
#define PARSE_MIDI
static std::vector<Midi*> midi;
std::vector<std::string> gMidiPortNames;
int gMidiVerbose = 1;
const int kMidiVerbosePrintLevel = 1;

void dumpMidi()
{
	if(midi.size() == 0)
	{
		printf("No MIDI device enabled\n");
		return;
	}
	printf("The following MIDI devices are enabled:\n");
	printf("%4s%20s %3s %3s %s\n",
			"Num",
			"Name",
			"In",
			"Out",
			"Pd channels"
	      );
	for(unsigned int n = 0; n < midi.size(); ++n)
	{
		printf("[%2d]%20s %3s %3s (%d-%d)\n",
			n,
			gMidiPortNames[n].c_str(),
			midi[n]->isInputEnabled() ? "x" : "_",
			midi[n]->isOutputEnabled() ? "x" : "_",
			n * 16 + 1,
			n * 16 + 16
		);
	}
}

Midi* openMidiDevice(std::string name, bool verboseSuccess = false, bool verboseError = false)
{
	Midi* newMidi;
	newMidi = new Midi();
	newMidi->readFrom(name.c_str());
	newMidi->writeTo(name.c_str());
#ifdef PARSE_MIDI
	newMidi->enableParser(true);
#else
	newMidi->enableParser(false);
#endif /* PARSE_MIDI */
	if(newMidi->isOutputEnabled())
	{
		if(verboseSuccess)
			printf("Opened MIDI device %s as output\n", name.c_str());
	}
	if(newMidi->isInputEnabled())
	{
		if(verboseSuccess)
			printf("Opened MIDI device %s as input\n", name.c_str());
	}
	if(!newMidi->isInputEnabled() && !newMidi->isOutputEnabled())
	{
		if(verboseError)
			fprintf(stderr, "Failed to open  MIDI device %s\n", name.c_str());
		return nullptr;
	} else {
		return newMidi;
	}
}

static unsigned int getPortChannel(int* channel){
	unsigned int port = 0;
	while(*channel >= 16){
		*channel -= 16;
		port += 1;
	}
	return port;
}

void Bela_MidiOutNoteOn(int channel, int pitch, int velocity) {
	int port = getPortChannel(&channel);
	if(gMidiVerbose >= kMidiVerbosePrintLevel)
		rt_printf("noteout _ port: %d, channel: %d, pitch: %d, velocity %d\n", port, channel, pitch, velocity);
	port < midi.size() && midi[port]->writeNoteOn(channel, pitch, velocity);
}

void Bela_MidiOutControlChange(int channel, int controller, int value) {
	int port = getPortChannel(&channel);
	if(gMidiVerbose >= kMidiVerbosePrintLevel)
		rt_printf("ctlout _ port: %d, channel: %d, controller: %d, value: %d\n", port, channel, controller, value);
	port < midi.size() && midi[port]->writeControlChange(channel, controller, value);
}

void Bela_MidiOutProgramChange(int channel, int program) {
	int port = getPortChannel(&channel);
	if(gMidiVerbose >= kMidiVerbosePrintLevel)
		rt_printf("pgmout _ port: %d, channel: %d, program: %d\n", port, channel, program);
	port < midi.size() && midi[port]->writeProgramChange(channel, program);
}

void Bela_MidiOutPitchBend(int channel, int value) {
	int port = getPortChannel(&channel);
	if(gMidiVerbose >= kMidiVerbosePrintLevel)
		rt_printf("bendout _ port: %d, channel: %d, value: %d\n", port, channel, value);
	port < midi.size() && midi[port]->writePitchBend(channel, value);
}

void Bela_MidiOutAftertouch(int channel, int pressure){
	int port = getPortChannel(&channel);
	if(gMidiVerbose >= kMidiVerbosePrintLevel)
		rt_printf("touchout _ port: %d, channel: %d, pressure: %d\n", port, channel, pressure);
	port < midi.size() && midi[port]->writeChannelPressure(channel, pressure);
}

void Bela_MidiOutPolyAftertouch(int channel, int pitch, int pressure){
	int port = getPortChannel(&channel);
	if(gMidiVerbose >= kMidiVerbosePrintLevel)
		rt_printf("polytouchout _ port: %d, channel: %d, pitch: %d, pressure: %d\n", port, channel, pitch, pressure);
	port < midi.size() && midi[port]->writePolyphonicKeyPressure(channel, pitch, pressure);
}

void Bela_MidiOutByte(int port, int byte){
	if(gMidiVerbose >= kMidiVerbosePrintLevel)
		rt_printf("port: %d, byte: %d\n", port, byte);
	if(port > (int)midi.size()){
		// if the port is out of range, redirect to the first port.
		rt_fprintf(stderr, "Port out of range, using port 0 instead\n");
		port = 0;
	}
	port < midi.size() && midi[port]->writeOutput(byte);
}

void Bela_printHook(const char *received){
	rt_printf("%s", received);
}

static DigitalChannelManager dcm;

void sendDigitalMessage(bool state, unsigned int delay, void* receiverName){
	libpd_float((const char*)receiverName, (float)state);
//	rt_printf("%s: %d\n", (char*)receiverName, state);
}

#ifdef ENABLE_TRILL
void setTrillPrintError()
{
	rt_fprintf(stderr, "bela_setTrill format is wrong. Should be:\n"
		"[mode <sensor_id> <prescaler_value>(\n"
		" or\n"
		"[threshold <sensor_id> <threshold_value>(\n"
		" or\n"
		"[prescaler <sensor_id> <prescaler_value>(\n");
}
#endif // ENABLE_TRILL

void Bela_listHook(const char *source, int argc, t_atom *argv)
{
#ifdef BELA_LIBPD_GUI
	if(0 == strcmp(source, "bela_guiOut"))
	{
		if(!libpd_is_float(&argv[0]))
		{
			rt_fprintf(stderr, "Wrong format for bela_gui, the first element should be a float\n");
			return;
		}
		unsigned int bufNum = libpd_get_float(&argv[1]);
		if(libpd_is_float(&argv[1])) // if the first element is a float, we send an array of floats
		{
			float buf[argc - 1];
			for(int n = 1; n < argc; ++n)
			{
				t_atom *a = &argv[n];
				if(!libpd_is_float(a))
				{
					rt_fprintf(stderr, "Wrong format for bela_gui\n"); // this should never happen, because then the selector would've not been "float"
					return;
				}
				buf[n - 1] = libpd_get_float(a);
			}
			gui.sendBuffer(bufNum, buf, argc - 1);
			return;
		} else { // otherwise we send each element of the list separately
			for(int n = 1; n < argc; ++n)
			{
				t_atom *a = &argv[n];
				if (libpd_is_float(a)) {
					float x = libpd_get_float(a);
					gui.sendBuffer(bufNum, x);
				} else if (libpd_is_symbol(a)) {
					const char *s = libpd_get_symbol(a);
					gui.sendBuffer(bufNum, s, strlen(s)); // TODO: should it be strlen(s)+1?
				}
			}
		}
		return;
	}
#endif // BELA_LIBPD_GUI
}
void Bela_messageHook(const char *source, const char *symbol, int argc, t_atom *argv){
	if(strcmp(source, "bela_setMidi") == 0)
	{
		if(0 == strcmp("verbose", symbol))
		{
			if(1 != argc || !libpd_is_float(argv))
			{
				rt_fprintf(stderr, "Wrong format for bela_setMidi, expected: [verbose <n>(\n");
			} else {
				gMidiVerbose = libpd_get_float(argv);
				rt_printf("MIDI verbose: %d\n", gMidiVerbose);
			}
			return;
		}
		int num[3] = {0, 0, 0};
		for(int n = 0; n < argc && n < 3; ++n)
		{
			if(!libpd_is_float(&argv[n]))
			{
				fprintf(stderr, "Wrong format for bela_setMidi, expected:[hw 1 0 0(");
				return;
			}
			num[n] = libpd_get_float(&argv[n]);
		}
		std::ostringstream deviceName;
		deviceName << symbol << ":" << num[0] << "," << num[1] << "," << num[2];
		printf("Adding Midi device: %s\n", deviceName.str().c_str());
		Midi* newMidi = openMidiDevice(deviceName.str(), false, true);
		if(newMidi)
		{
			midi.push_back(newMidi);
			gMidiPortNames.push_back(deviceName.str());
		}
		dumpMidi();
		return;
	}
	if(strcmp(source, "bela_setDigital") == 0){
		// symbol is the direction, argv[0] is the channel, argv[1] (optional)
		// is signal("sig" or "~") or message("message", default) rate
		bool isMessageRate = true; // defaults to message rate
		bool direction = 0; // initialize it just to avoid the compiler's warning
		bool disable = false;
		if(strcmp(symbol, "in") == 0){
			direction = INPUT;
		} else if(strcmp(symbol, "out") == 0){
			direction = OUTPUT;
		} else if(strcmp(symbol, "disable") == 0){
			disable = true;
		} else {
			return;
		}
		if(argc == 0){
			return;
		} else if (libpd_is_float(&argv[0]) == false){
			return;
		}
		int channel = libpd_get_float(&argv[0]) - gLibpdDigitalChannelOffset;
		if(disable == true){
			dcm.unmanage(channel);
			return;
		}
		if(argc >= 2){
			t_atom* a = &argv[1];
			if(libpd_is_symbol(a)){
				const char *s = libpd_get_symbol(a);
				if(strcmp(s, "~") == 0  || strncmp(s, "sig", 3) == 0){
					isMessageRate = false;
				}
			}
		}
		dcm.manage(channel, direction, isMessageRate);
		return;
	}
#ifdef BELA_LIBPD_GUI
	if(0 == strcmp(source, "bela_setGui"))
	{
		if(0 == strcmp(symbol, "new"))
		{
			if(
				argc < 2
				|| !libpd_is_symbol(argv)
				|| !libpd_is_symbol(argv + 1)
			)
			{
				return;
			}
			const char* mode = libpd_get_symbol(argv);
			const char* name = libpd_get_symbol(argv + 1);
			if(0 == strcmp(mode, "control"))
			{
				gGuiControlBuffers.emplace_back(name);
				return;
			}
			if(0 == strcmp(mode, "array"))
			{
				// because of
				// https://github.com/libpd/libpd/issues/274
				// (again), we cannot access the arrays right
				// here (as it would deadlock on loadbang), so
				// we have to defer creation of the Gui
				// buffers until render() runs
				gGuiDataBuffers.emplace_back(bufferDescription{.name = name, .id = -1, .size = 0});
				return;
			}
			return;
		}
	}
#endif // BELA_LIBPD_GUI
#ifdef ENABLE_TRILL
	if(0 == strcmp(source, "bela_setTrill"))
	{
		if(0 == strcmp(symbol, "new"))
		{
			bool err = false;

			uint8_t address = 0xff;
			if(argc < 3)
				err = true;
			else if (!libpd_is_symbol(argv) // sensor_id
				|| !libpd_is_float(argv + 1) // bus
				|| !libpd_is_symbol(argv + 2) // device
			)
				err = true;
			if(argc >= 4)
			{
				if(libpd_is_float(argv + 3))
					address = libpd_get_float(argv + 3);
				else
					err = true;
			}
			if(err)
			{
				rt_fprintf(stderr, "bela_setTrill wrong format. Should be:\n"
					"[new <sensor_id> <bus> <device> <address>(\n");
				return;
			}
			const char* name = libpd_get_symbol(argv);
			unsigned int bus = libpd_get_float(argv + 1);
			const char* deviceString = libpd_get_symbol(argv + 2);
			Trill::Device device = Trill::getDeviceFromName(deviceString);

			Trill* trill = new Trill(bus, device, address);
			if(Trill::NONE == trill->deviceType())
			{
				rt_fprintf(stderr, "Unable to create Trill %s device `%s` on bus %u at ", deviceString, name, bus);
				if(128 < address)
					rt_fprintf(stderr, "default address. ");
				else
					rt_fprintf(stderr, "address: %#x (%d). ", address, address);
				rt_fprintf(stderr, "Is the device connected?\n");
				return;
			}
			gTouchSensors.emplace_back(std::string(name), trill);
			gTrillAcks.push_back(name);
			//an ack is sent to Pd during the next audio callback because of https://github.com/libpd/libpd/issues/274
			return;
		}
		if(argc < 1 || !libpd_is_symbol(argv))
		{
			rt_fprintf(stderr, "bela_setTrill: wrong format. It should be\n"
					"[<command> <sensor_id> ...(");
			return;
		}
		const char* sensorId = libpd_get_symbol(argv);
		int idx = getIdxFromId(sensorId, gTouchSensors);
		if(idx < 0)
		{
			rt_fprintf(stderr, "bela_setTrill sensor_id unknown: %s\n", sensorId);
			return;
		}
		if(0 == strcmp(symbol, "updateBaseline"))
		{
			gTouchSensors[idx].second->updateBaseline();
			return;
		}
		if(0 == strcmp(symbol, "mode"))
		{
			if(argc < 2
				|| !libpd_is_symbol(argv)
				|| !libpd_is_symbol(argv + 1)
			) {
				setTrillPrintError();
				return;
			}
			const char* modeString = libpd_get_symbol(argv + 1);
			Trill::Mode mode = Trill::getModeFromName(modeString);
			gTouchSensors[idx].second->setMode(mode);
		}
		if(
			0 == strcmp(symbol, "threshold")
			|| 0 == strcmp(symbol, "prescaler")
		)
		{
			if(
				argc < 2
				|| !libpd_is_symbol(argv)
				|| !libpd_is_float(argv + 1)
			  ) {
				setTrillPrintError();
				return;
			}
			float value = libpd_get_float(argv + 1);
			if(0 == strcmp(symbol, "threshold"))
			{
				gTouchSensors[idx].second->setNoiseThreshold(value);
			}
			if(0 == strcmp(symbol, "prescaler"))
			{
				if(Trill::prescalerMax < value || 0 > value)
				{
					if(0 == value)
						value = 0;
					if(Trill::prescalerMax < value)
						value = Trill::prescalerMax;
					rt_printf("bela_setTrill prescaler value out of range, clipping to %u\n", value);
				}
				gTouchSensors[idx].second->setPrescaler(value);
			}
			return;
		}
		return;
	}
#endif // ENABLE_TRILL
}

void Bela_floatHook(const char *source, float value){
	// let's make this as optimized as possible for built-in digital Out parsing
	// the built-in digital receivers are of the form "bela_digitalOutXX" where XX is between gLibpdDigitalChannelOffset and (gLibpdDigitalCHannelOffset+gDigitalChannelsInUse)
	static int prefixLength = 15; // strlen("bela_digitalOut")
	if(strncmp(source, "bela_digitalOut", prefixLength)==0){
		if(source[prefixLength] != 0){ //the two ifs are used instead of if(strlen(source) >= prefixLength+2)
			if(source[prefixLength + 1] != 0){
				// quickly convert the suffix to integer, assuming they are numbers, avoiding to call atoi
				int receiver = ((source[prefixLength] - 48) * 10);
				receiver += (source[prefixLength+1] - 48);
				unsigned int channel = receiver - gLibpdDigitalChannelOffset; // go back to the actual Bela digital channel number
				if(channel < gDigitalChannelsInUse){ //number of digital channels
					dcm.setValue(channel, value);
				}
			}
		}
	}
}



std::vector<std::string> gReceiverInputNames;
std::vector<std::string> gReceiverOutputNames;
void generateDigitalNames(unsigned int numDigitals, unsigned int libpdOffset, std::vector<std::string>& receiverInputNames, std::vector<std::string>& receiverOutputNames)
{
	std::string inBaseString = "bela_digitalIn";
	std::string outBaseString = "bela_digitalOut";
	for(unsigned int i = 0; i<numDigitals; i++)
	{
		receiverInputNames.push_back(inBaseString + std::to_string(i+libpdOffset));
		receiverOutputNames.push_back(outBaseString + std::to_string(i+libpdOffset));
	}
}

void printDigitalNames(std::vector<std::string>& receiverInputNames, std::vector<std::string>& receiverOutputNames)
{
	printf("DIGITAL INPUTS\n");
	for(unsigned int i=0; i<gDigitalChannelsInUse; i++)
		printf("%s\n", receiverInputNames[i].c_str());
	printf("DIGITAL OUTPUTS\n");
	for(unsigned int i=0; i<gDigitalChannelsInUse; i++)
		printf("%s\n", receiverOutputNames[i].c_str());
}

static char multiplexerArray[] = {"bela_multiplexer"};
static int multiplexerArraySize = 0;
static bool pdMultiplexerActive = false;

#ifdef PD_THREADED_IO
void fdLoop(void* arg){
	while(!Bela_stopRequested()){
		sys_doio();
		usleep(3000);
	}
}
#endif /* PD_THREADED_IO */

Scope scope;
float* gScopeOut;
void* gPatch;
bool gDigitalEnabled = 0;

bool setup(BelaContext *context, void *userData)
{
#ifdef BELA_LIBPD_GUI
	gui.setup(context->projectName);
	gui.setControlDataCallback(guiControlDataCallback, nullptr);
	gGuiPipe.setup("guiControlPipe", 16384);
#endif // BELA_LIBPD_GUI
	// Check Pd's version
	int major, minor, bugfix;
	sys_getversion(&major, &minor, &bugfix);
	printf("Running Pd %d.%d-%d\n", major, minor, bugfix);
	// We requested in Bela_userSettings() to have uniform sampling rate for audio
	// and analog and non-interleaved buffers.
	// So let's check this actually happened
	if(context->analogSampleRate != context->audioSampleRate)
	{
		fprintf(stderr, "The sample rate of analog and audio must match. Try running with --uniform-sample-rate\n");
		return false;
	}
	if(context->flags & BELA_FLAG_INTERLEAVED)
	{
		fprintf(stderr, "The audio and analog channels must be interleaved.\n");
		return false;
	}

	if(context->digitalFrames > 0 && context->digitalChannels > 0)
		gDigitalEnabled = 1;

	// add here other devices you need
	gMidiPortNames.push_back("hw:1,0,0");
	//gMidiPortNames.push_back("hw:0,0,0");
	//gMidiPortNames.push_back("hw:1,0,1");

	scope.setup(gScopeChannelsInUse, context->audioSampleRate);
	gScopeOut = new float[gScopeChannelsInUse];

	// Check first of all if the patch file exists. Will actually open it later.
	char file[] = "_main.pd";
	char folder[] = "./";
	unsigned int strSize = strlen(file) + strlen(folder) + 1;
	char* str = (char*)malloc(sizeof(char) * strSize);
	snprintf(str, strSize, "%s%s", folder, file);
	if(access(str, F_OK) == -1 ) {
		printf("Error file %s/%s not found. The %s file should be your main patch.\n", folder, file, file);
		return false;
	}
	free(str);

	// analog setup
	gAnalogChannelsInUse = context->analogInChannels;
	gDigitalChannelsInUse = context->digitalChannels;
	printf("Audio channels in use: %d\n", context->audioOutChannels);
	printf("Analog channels in use: %d\n", gAnalogChannelsInUse);
	printf("Digital channels in use: %d\n", gDigitalChannelsInUse);

	// Channel distribution
	gFirstAnalogInChannel = std::max(context->audioInChannels, context->audioOutChannels);
	gFirstAnalogOutChannel = gFirstAnalogInChannel;
	gFirstDigitalChannel = gFirstAnalogInChannel + std::max(context->analogInChannels, context->analogOutChannels);
	if(gFirstDigitalChannel < minFirstDigitalChannel)
		gFirstDigitalChannel = minFirstDigitalChannel; //for backwards compatibility
	gLibpdDigitalChannelOffset = gFirstDigitalChannel + 1;
	gFirstScopeChannel = gFirstDigitalChannel + gDigitalChannelsInUse;

	gChannelsInUse = gFirstScopeChannel + gScopeChannelsInUse;

	// Create receiverNames for digital channels
	generateDigitalNames(gDigitalChannelsInUse, gLibpdDigitalChannelOffset, gReceiverInputNames, gReceiverOutputNames);

	// digital setup
	if(gDigitalEnabled)
	{
		dcm.setCallback(sendDigitalMessage);
		if(gDigitalChannelsInUse > 0){
			for(unsigned int ch = 0; ch < gDigitalChannelsInUse; ++ch){
				dcm.setCallbackArgument(ch, (void*) gReceiverInputNames[ch].c_str());
			}
		}
	}

	unsigned int n = 0;
	while(n < gMidiPortNames.size())
	{
		Midi* newMidi = openMidiDevice(gMidiPortNames[n], false, false);
		if(newMidi)
		{
			midi.push_back(newMidi);
			++n;
		} else {
			gMidiPortNames.erase(gMidiPortNames.begin() + n);
		}
	}
	dumpMidi();

	// check that we are not running with a blocksize smaller than gLibPdBlockSize
	gLibpdBlockSize = libpd_blocksize();
	if(context->audioFrames < gLibpdBlockSize){
		fprintf(stderr, "Error: minimum block size must be %d\n", gLibpdBlockSize);
		return false;
	}

	// set hooks before calling libpd_init
	libpd_set_printhook(Bela_printHook);
	libpd_set_floathook(Bela_floatHook);
	libpd_set_listhook(Bela_listHook);
	libpd_set_messagehook(Bela_messageHook);
	libpd_set_noteonhook(Bela_MidiOutNoteOn);
	libpd_set_controlchangehook(Bela_MidiOutControlChange);
	libpd_set_programchangehook(Bela_MidiOutProgramChange);
	libpd_set_pitchbendhook(Bela_MidiOutPitchBend);
	libpd_set_aftertouchhook(Bela_MidiOutAftertouch);
	libpd_set_polyaftertouchhook(Bela_MidiOutPolyAftertouch);
	libpd_set_midibytehook(Bela_MidiOutByte);

	//initialize libpd. This clears the search path
	libpd_init();
	//Add the current folder to the search path for externals
	libpd_add_to_search_path(".");
	libpd_add_to_search_path("../pd-externals");

	libpd_init_audio(gChannelsInUse, gChannelsInUse, context->audioSampleRate);
	gInBuf = get_sys_soundin();
	gOutBuf = get_sys_soundout();

	// start DSP:
	// [; pd dsp 1(
	libpd_start_message(1);
	libpd_add_float(1.0f);
	libpd_finish_message("pd", "dsp");

	// Bind your receivers here
	for(unsigned int i = 0; i < gDigitalChannelsInUse; i++)
		libpd_bind(gReceiverOutputNames[i].c_str());
	libpd_bind("bela_setDigital");
	libpd_bind("bela_setMidi");
#ifdef BELA_LIBPD_GUI
	libpd_bind("bela_guiOut");
	libpd_bind("bela_setGui");
#endif // BELA_LIBPD_GUI
#ifdef ENABLE_TRILL
	libpd_bind("bela_setTrill");
#endif // ENABLE_TRILL

	// open patch:
	gPatch = libpd_openfile(file, folder);
	if(gPatch == NULL){
		printf("Error: file %s/%s is corrupted.\n", folder, file);
		return false;
	}

	// If the user wants to use the multiplexer capelet,
	// the patch will have to contain an array called "bela_multiplexer"
	// and a receiver [r bela_multiplexerChannels]
	if(context->multiplexerChannels > 0 && libpd_arraysize(multiplexerArray) >= 0){
		pdMultiplexerActive = true;
		multiplexerArraySize = context->multiplexerChannels * context->analogInChannels;
		// [; bela_multiplexer ` multiplexerArraySize` resize(
		libpd_start_message(1);
		libpd_add_float(multiplexerArraySize);
		libpd_finish_message(multiplexerArray, "resize");
		// [; bela_multiplexerChannels `context->multiplexerChannels`(
		libpd_float("bela_multiplexerChannels", context->multiplexerChannels);
	}

	// Tell Pd that we will manage the io loop,
	// and we do so in an Auxiliary Task
#ifdef PD_THREADED_IO
	sys_dontmanageio(1);
	AuxiliaryTask fdTask;
	fdTask = Bela_createAuxiliaryTask(fdLoop, 50, "libpd-fdTask", NULL);
	Bela_scheduleAuxiliaryTask(fdTask);
#endif /* PD_THREADED_IO */

	dcm.setVerbose(false);
#ifdef ENABLE_TRILL
	gTrillTask = Bela_createAuxiliaryTask(readTouchSensors, 51, "touchSensorRead", NULL);
	gTrillPipe.setup("trillPipe", 1024);
#endif // ENABLE_TRILL
#ifdef ENABLE_EVO
	if(gEvo.initI2C_RW(gEvoI2cBus, gEvoI2cAddress, -1))
		return false; // wrong bus, or address out of range
	if(gEvo.readI2C()) 	//verify that we can read from the device
		return false; // ... or fail otherwise
	Bela_runAuxiliaryTask(evoReadTask, 50);
#endif // ENABLE_EVO
	return true;
}

void render(BelaContext *context, void *userData)
{
#ifdef BELA_LIBPD_GUI
	while(gGuiControlBuffers.size()) // this won't change within the loop, but it's good not to have to use a separate flag
	{
		static struct guiControlMessageHeader header;
		static bool waitingForHeader = true;
		if(waitingForHeader)
		{
			int ret = gGuiPipe.readRt(header);
			if(1 != ret)
				break;
			else
				waitingForHeader = false;
		}
		if(!waitingForHeader)
		{
			char payload[header.size];
			int ret = gGuiPipe.readRt(&payload[0], header.size);
			if(header.size != ret)
			{
				break;
			}
			const char* name = gGuiControlBuffers[header.id].c_str();
			if('f' == header.type)
			{
				if(header.size != sizeof(float))
				{
					rt_fprintf(stderr, "Unexpected message length for float: %u\n", header.size);
					continue;
				}
				float value = ((float*)payload)[0];
				libpd_start_message(1);
				libpd_add_float(value);
				libpd_finish_message("bela_guiControl", name);
			}
			if('s' == header.type)
			{
				libpd_symbol(name, payload);
			}
			waitingForHeader = true;
		}
	}
	for(auto& b : gGuiDataBuffers)
	{
		int id = b.id;
		int size = b.size;
		const char* name = b.name.c_str();
		if(id < 0)
		{
			// initialize
			size = libpd_arraysize(name);
			if(size <= 0)
			{
				continue;
			} else {
				// this is thread-unsafe: what happens if this causes reallocation while the Gui thread is writing to a buffer?
				id = gui.setBuffer('f', size);
				b.id = id;
				b.size = size;
				DataBuffer& dataBuffer = gui.getDataBuffer(id);
				// initialize gui buffer with the initial content of the array
				libpd_read_array(dataBuffer.getAsFloat(), b.name.c_str(), 0, size);
			}
		}
		DataBuffer& dataBuffer = gui.getDataBuffer(b.id);
		libpd_write_array(b.name.c_str(), 0, dataBuffer.getAsFloat(), dataBuffer.getNumElements());
	}
#endif // BELA_LIBPD_GUI
#ifdef ENABLE_TRILL
	for(auto& name : gTrillAcks)
	{
		unsigned int idx = getIdxFromId(name.c_str(), gTouchSensors);
		libpd_start_message(3);
		libpd_add_symbol(Trill::getNameFromDevice(gTouchSensors[idx].second->deviceType()).c_str());
		libpd_add_float(gTouchSensors[idx].second->getAddress());
		libpd_add_symbol(Trill::getNameFromMode(gTouchSensors[idx].second->getMode()).c_str());
		libpd_finish_message("bela_trillCreated", name.c_str());
	}
	gTrillAcks.resize(0);
	bool doTrill = false;
	for(auto& t : gTouchSensors)
	{
		if(Trill::NONE != t.second->deviceType())
		{
			doTrill = true;
			break;
		}
	}
	if(doTrill)
	{
		int idx;
		while(gTrillPipe.readRt(idx) > 0)
		{
			Trill& touchSensor = *gTouchSensors[idx].second;
			const char* sensorId = gTouchSensors[idx].first.c_str();
			if(Trill::Device::NONE == touchSensor.deviceType())
				continue;

			const Trill::Mode mode = touchSensor.getMode();
			if(Trill::DIFF == mode || Trill::RAW == mode || Trill::BASELINE == mode)
			{
				libpd_start_message(touchSensor.getNumChannels());
				for(unsigned int n = 0; n < touchSensor.getNumChannels(); ++n)
				{
					libpd_add_float(touchSensor.rawData[n]);
				}
			} else if(Trill::CENTROID == mode)
			{
				if(touchSensor.is1D()) {
					libpd_start_message(2 * touchSensor.getNumTouches() + 1);
					libpd_add_float(touchSensor.getNumTouches());
					for(int i = 0; i < touchSensor.getNumTouches(); i++) {
						libpd_add_float(touchSensor.touchLocation(i));
						libpd_add_float(touchSensor.touchSize(i));
					}
				} else if (touchSensor.is2D()) {
					int numTouches = touchSensor.compoundTouchSize() > 0;
					libpd_start_message(2 * numTouches + 1);
					libpd_add_float(numTouches > 0);
					if(numTouches)
					{
						libpd_add_float(touchSensor.compoundTouchHorizontalLocation());
						libpd_add_float(touchSensor.compoundTouchLocation());
						libpd_add_float(touchSensor.compoundTouchSize());
					}
				}
			}
			else
				continue;
			libpd_finish_message("bela_trill", sensorId);
		}

		static int count = 0;
		unsigned int readIntervalSamples = touchSensorSleepInterval * context->audioSampleRate;
		count += context->audioFrames;
		if(count > readIntervalSamples)
		{
			Bela_scheduleAuxiliaryTask(gTrillTask);
			count -= readIntervalSamples;
		}
	}
#endif // ENABLE_TRILL
#ifdef PARSE_MIDI
	int num;
	for(unsigned int port = 0; port < midi.size(); ++port){
		while((num = midi[port]->getParser()->numAvailableMessages()) > 0){
			static MidiChannelMessage message;
			message = midi[port]->getParser()->getNextChannelMessage();
			if(gMidiVerbose >= kMidiVerbosePrintLevel)
			{
				rt_printf("On port %d (%s): ", port, gMidiPortNames[port].c_str());
				message.prettyPrint(); // use this to print beautified message (channel, data bytes)
			}
			switch(message.getType()){
				case kmmNoteOn:
				{
					int noteNumber = message.getDataByte(0);
					int velocity = message.getDataByte(1);
					int channel = message.getChannel();
					libpd_noteon(channel + port * 16, noteNumber, velocity);
					break;
				}
				case kmmNoteOff:
				{
					/* PureData does not seem to handle noteoff messages as per the MIDI specs,
					 * so that the noteoff velocity is ignored. Here we convert them to noteon
					 * with a velocity of 0.
					 */
					int noteNumber = message.getDataByte(0);
	//				int velocity = message.getDataByte(1); // would be ignored by Pd
					int channel = message.getChannel();
					libpd_noteon(channel + port * 16, noteNumber, 0);
					break;
				}
				case kmmControlChange:
				{
					int channel = message.getChannel();
					int controller = message.getDataByte(0);
					int value = message.getDataByte(1);
					libpd_controlchange(channel + port * 16, controller, value);
					break;
				}
				case kmmProgramChange:
				{
					int channel = message.getChannel();
					int program = message.getDataByte(0);
					libpd_programchange(channel + port * 16, program);
					break;
				}
				case kmmPolyphonicKeyPressure:
				{
					int channel = message.getChannel();
					int pitch = message.getDataByte(0);
					int value = message.getDataByte(1);
					libpd_polyaftertouch(channel + port * 16, pitch, value);
					break;
				}
				case kmmChannelPressure:
				{
					int channel = message.getChannel();
					int value = message.getDataByte(0);
					libpd_aftertouch(channel + port * 16, value);
					break;
				}
				case kmmPitchBend:
				{
					int channel = message.getChannel();
					int value =  ((message.getDataByte(1) << 7)| message.getDataByte(0)) - 8192;
					libpd_pitchbend(channel + port * 16, value);
					break;
				}
				case kmmSystem:
				// currently Bela only handles sysrealtime, and it does so pretending it is a channel message with no data bytes, so we have to re-assemble the status byte
				{
					int channel = message.getChannel();
					int status = message.getStatusByte();
					int byte = channel | status;
					libpd_sysrealtime(port, byte);
					break;
				}
				case kmmNone:
				case kmmAny:
					break;
			}
		}
	}
#else
	int input;
	for(unsigned int port = 0; port < NUM_MIDI_PORTS; ++port){
		while((input = midi[port].getInput()) >= 0){
			libpd_midibyte(port, input);
		}
	}
#endif /* PARSE_MIDI */
#ifdef ENABLE_EVO
	static uint64_t evoLastSent = 0;
	if(context->audioFramesElapsed - evoLastSent > gEvoSendIntervalMs * 0.001f * context->audioSampleRate)
	{
		libpd_float(gEvoReceiverName, gEvoValue);
		evoLastSent = context->audioFramesElapsed;
	}
#endif // ENABLE_EVO
	unsigned int numberOfPdBlocksToProcess = context->audioFrames / gLibpdBlockSize;

	// Remember: we have non-interleaved buffers and the same sampling rate for
	// analogs, audio and digitals
	for(unsigned int tick = 0; tick < numberOfPdBlocksToProcess; ++tick)
	{
		//audio input
		for(int n = 0; n < context->audioInChannels; ++n)
		{
			memcpy(
				gInBuf + n * gLibpdBlockSize,
				context->audioIn + tick * gLibpdBlockSize + n * context->audioFrames,
				sizeof(context->audioIn[0]) * gLibpdBlockSize
			);
		}

		// analog input
		for(int n = 0; n < context->analogInChannels; ++n)
		{
			memcpy(
				gInBuf + gLibpdBlockSize * gFirstAnalogInChannel + n * gLibpdBlockSize,
				context->analogIn + tick * gLibpdBlockSize + n * context->analogFrames,
				sizeof(context->analogIn[0]) * gLibpdBlockSize
			);
		}
		// multiplexed analog input
		if(pdMultiplexerActive)
		{
			// we do not disable regular analog inputs if muxer is active, because user may have bridged them on the board and
			// they may be using half of them at a high sampling-rate
			static int lastMuxerUpdate = 0;
			if(++lastMuxerUpdate == multiplexerArraySize){
				lastMuxerUpdate = 0;
				libpd_write_array(multiplexerArray, 0, (float *const)context->multiplexerAnalogIn, multiplexerArraySize);
			}
		}

		unsigned int digitalFrameBase = gLibpdBlockSize * tick;
		unsigned int j;
		unsigned int k;
		float* p0;
		float* p1;
		// digital input
		if(gDigitalEnabled)
		{
			// digital in at message-rate
			dcm.processInput(&context->digital[digitalFrameBase], gLibpdBlockSize);

			// digital in at signal-rate
			for (j = 0, p0 = gInBuf; j < gLibpdBlockSize; j++, p0++) {
				unsigned int digitalFrame = digitalFrameBase + j;
				for (k = 0, p1 = p0 + gLibpdBlockSize * gFirstDigitalChannel;
						k < 16; ++k, p1 += gLibpdBlockSize) {
					if(dcm.isSignalRate(k) && dcm.isInput(k)){ // only process input channels that are handled at signal rate
						*p1 = digitalRead(context, digitalFrame, k);
					}
				}
			}
		}

		libpd_process_sys(); // process the block

		// digital outputs
		if(gDigitalEnabled)
		{
			// digital out at signal-rate
			for (j = 0, p0 = gOutBuf; j < gLibpdBlockSize; ++j, ++p0) {
				unsigned int digitalFrame = (digitalFrameBase + j);
				for (k = 0, p1 = p0  + gLibpdBlockSize * gFirstDigitalChannel;
					k < context->digitalChannels; k++, p1 += gLibpdBlockSize)
				{
					if(dcm.isSignalRate(k) && dcm.isOutput(k)){ // only process output channels that are handled at signal rate
						digitalWriteOnce(context, digitalFrame, k, *p1 > 0.5);
					}
				}
			}

			// digital out at message-rate
			dcm.processOutput(&context->digital[digitalFrameBase], gLibpdBlockSize);
		}

		// scope output
		for (j = 0, p0 = gOutBuf; j < gLibpdBlockSize; ++j, ++p0) {
			for (k = 0, p1 = p0 + gLibpdBlockSize * gFirstScopeChannel; k < gScopeChannelsInUse; k++, p1 += gLibpdBlockSize) {
				gScopeOut[k] = *p1;
			}
			scope.log(gScopeOut[0], gScopeOut[1], gScopeOut[2], gScopeOut[3]);
		}

		// audio output
		for(int n = 0; n < context->audioOutChannels; ++n)
		{
			memcpy(
				context->audioOut + tick * gLibpdBlockSize + n * context->audioFrames,
				gOutBuf + n * gLibpdBlockSize,
				sizeof(context->audioOut[0]) * gLibpdBlockSize
			);
		}

		//analog output
		for(int n = 0; n < context->analogOutChannels; ++n)
		{
			memcpy(
				context->analogOut + tick * gLibpdBlockSize + n * context->analogFrames,
				gOutBuf + gLibpdBlockSize * gFirstAnalogOutChannel + n * gLibpdBlockSize,
				sizeof(context->analogOut[0]) * gLibpdBlockSize
			);
		}
	}
}

void cleanup(BelaContext *context, void *userData)
{
	for(auto a : midi)
	{
		delete a;
	}
#ifdef ENABLE_TRILL
	for(auto t : gTouchSensors)
	{
		// t.first is a std::string, so the memory will be deallocated automatically
		delete t.second;
	}
#endif // ENABLE_TRILL
	libpd_closefile(gPatch);
	delete [] gScopeOut;
}