robert@464: /*
robert@464:  ____  _____ _        _    
robert@464: | __ )| ____| |      / \   
robert@464: |  _ \|  _| | |     / _ \  
robert@464: | |_) | |___| |___ / ___ \ 
robert@464: |____/|_____|_____/_/   \_\
robert@464: 
robert@464: The platform for ultra-low latency audio and sensor processing
robert@464: 
robert@464: http://bela.io
robert@464: 
robert@464: A project of the Augmented Instruments Laboratory within the
robert@464: Centre for Digital Music at Queen Mary University of London.
robert@464: http://www.eecs.qmul.ac.uk/~andrewm
robert@464: 
robert@464: (c) 2016 Augmented Instruments Laboratory: Andrew McPherson,
robert@464:   Astrid Bin, Liam Donovan, Christian Heinrichs, Robert Jack,
robert@464:   Giulio Moro, Laurel Pardue, Victor Zappi. All rights reserved.
robert@464: 
robert@464: The Bela software is distributed under the GNU Lesser General Public License
robert@464: (LGPL 3.0), available here: https://www.gnu.org/licenses/lgpl-3.0.txt
robert@464: */
robert@464: 
robert@464: 
robert@464: #include <Bela.h>
robert@464: #include <Midi.h>
robert@464: #include <stdlib.h>
robert@464: #include <rtdk.h>
robert@464: #include <cmath>
robert@464: 
robert@464: float gFreq;
robert@464: float gPhaseIncrement = 0;
robert@464: bool gIsNoteOn = 0;
robert@464: int gVelocity = 0;
robert@464: float gSamplingPeriod = 0;
robert@464: 
robert@464: void midiMessageCallback(MidiChannelMessage message, void* arg){
robert@464: 	if(arg != NULL){
robert@464: 		rt_printf("Message from midi port %d: ", *(int*)arg);
robert@464: 	}
robert@464: 	message.prettyPrint();
robert@464: 	if(message.getType() == kmmNoteOn){
robert@464: 		gFreq = powf(2, (message.getDataByte(0)-69)/12.0f) * 440;
robert@464: 		gVelocity = message.getDataByte(1);
robert@464: 		gPhaseIncrement = 2 * M_PI * gFreq * gSamplingPeriod;
robert@464: 		gIsNoteOn = gVelocity > 0;
robert@464: 		rt_printf("v0:%f, ph: %6.5f, gVelocity: %d\n", gFreq, gPhaseIncrement, gVelocity);
robert@464: 	}
robert@464: }
robert@464: // setup() is called once before the audio rendering starts.
robert@464: // Use it to perform any initialisation and allocation which is dependent
robert@464: // on the period size or sample rate.
robert@464: //
robert@464: // userData holds an opaque pointer to a data structure that was passed
robert@464: // in from the call to initAudio().
robert@464: //
robert@464: // Return true on success; returning false halts the program.
robert@464: Midi midi;
robert@464: int gMidiPort0 = 0;
robert@464: bool setup(BelaContext *context, void *userData)
robert@464: {
robert@464: 	midi.readFrom(gMidiPort0);
robert@464: 	midi.writeTo(gMidiPort0);
robert@464: 	midi.enableParser(true);
robert@464: 	midi.setParserCallback(midiMessageCallback, &gMidiPort0);
robert@464: 	if(context->analogFrames == 0) {
robert@464: 		rt_printf("Error: this example needs the analog I/O to be enabled\n");
robert@464: 		return false;
robert@464: 	}
chris@543: 
chris@543: 	if(context->audioOutChannels <= 2 ||
chris@543: 		context->analogOutChannels <= 2){
chris@543: 		printf("Error: for this project, you need at least 2 analog and audio output channels.\n");
chris@543: 		return false;
chris@543: 	}
chris@543: 
robert@464: 	gSamplingPeriod = 1/context->audioSampleRate;
robert@464: 	return true;
robert@464: }
robert@464: 
robert@464: // render() is called regularly at the highest priority by the audio engine.
robert@464: // Input and output are given from the audio hardware and the other
robert@464: // ADCs and DACs (if available). If only audio is available, numMatrixFrames
robert@464: // will be 0.
robert@464: 
robert@464: 
robert@464: enum {kVelocity, kNoteOn, kNoteNumber};
robert@464: void render(BelaContext *context, void *userData)
robert@464: {
robert@464: // one way of getting the midi data is to parse them yourself
robert@464: //	(you should set midi.enableParser(false) above):
robert@464: /*
robert@464: 	static midi_byte_t noteOnStatus = 0x90; //on channel 1
robert@464: 	static int noteNumber = 0;
robert@464: 	static int waitingFor = kNoteOn;
robert@464: 	static int playingNote = -1;
robert@464: 	int message;
robert@464: 	while ((message = midi.getInput()) >= 0){
robert@464: 		rt_printf("%d\n", message);
robert@464: 		switch(waitingFor){
robert@464: 		case kNoteOn:
robert@464: 			if(message == noteOnStatus){
robert@464: 				waitingFor = kNoteNumber;
robert@464: 			}
robert@464: 			break;
robert@464: 		case kNoteNumber:
robert@464: 			if((message & (1<<8)) == 0){
robert@464: 				noteNumber = message;
robert@464: 				waitingFor = kVelocity;
robert@464: 			}
robert@464: 			break;
robert@464: 		case kVelocity:
robert@464: 			if((message & (1<<8)) == 0){
robert@464: 				int _velocity = message;
robert@464: 				waitingFor = kNoteOn;
robert@464: 				// "monophonic" behaviour, with priority to the latest note on
robert@464: 				// i.e.: a note off from a previous note does not stop the current note
robert@464: 				// still you might end up having a key down and no note being played if you pressed and released another
robert@464: 				// key in the meantime
robert@464: 				if(_velocity == 0 && noteNumber == playingNote){
robert@464: 					noteOn = false;
robert@464: 					playingNote = -1;
robert@464: 					velocity = _velocity;
robert@464: 				} else if (_velocity > 0) {
robert@464: 					noteOn = true;
robert@464: 					velocity = _velocity;
robert@464: 					playingNote = noteNumber;
robert@464: 					f0 = powf(2, (playingNote-69)/12.0f) * 440;
robert@464: 					phaseIncrement = 2 * M_PI * f0 / context->audioSampleRate;
robert@464: 				}
robert@464: 				rt_printf("NoteOn: %d, NoteNumber: %d, velocity: %d\n", noteOn, noteNumber, velocity);
robert@464: 			}
robert@464: 			break;
robert@464: 		}
robert@464: 	}
robert@464: */
robert@464: 	/*
robert@464: 	int num;
robert@464: 	//alternatively, you can use the built-in parser (only processes channel messages at the moment).
robert@464: 	while((num = midi.getParser()->numAvailableMessages()) > 0){
robert@464: 		static MidiChannelMessage message;
robert@464: 		message = midi.getParser()->getNextChannelMessage();
robert@464: 		message.prettyPrint();
robert@464: 		if(message.getType() == kmmNoteOn){
robert@464: 			f0 = powf(2, (message.getDataByte(0)-69)/12.0f) * 440;
robert@464: 			velocity = message.getDataByte(1);
robert@464: 			phaseIncrement = 2 * M_PI * f0 / context->audioSampleRate;
robert@464: 			noteOn = velocity > 0;
robert@464: 			rt_printf("v0:%f, ph: %6.5f, velocity: %d\n", f0, phaseIncrement, gVelocity);
robert@464: 		}
robert@464: 	}
robert@464: 	 */
robert@464: 	// the following block toggles the LED on an Owl pedal
robert@464: 	// and asks the pedal to return the status of the LED
robert@464: 	// using MIDI control changes
robert@464: 	for(unsigned int n = 0; n < context->analogFrames; n++){
robert@464: 		static int count = 0;
robert@464: 		static bool state = 0;
robert@464: 		analogWriteOnce(context, n, 1, state);
robert@464: 		if(count % 40000 == 0){
robert@464: 			state = !state;
robert@464: 			midi_byte_t bytes[6] = {176, 30, (char)(state*127), 176, 67, 30}; // toggle the OWL led and ask for the led status
robert@464: 			midi.writeOutput(bytes, 6);
robert@464: 		}
robert@464: 		count++;
robert@464: 	}
robert@464: 	for(unsigned int n = 0; n < context->audioFrames; n++){
robert@464: 		if(gIsNoteOn == 1){
robert@464: 			static float phase = 0;
robert@464: 			phase += gPhaseIncrement;
robert@464: 			if(phase > 2 * M_PI)
robert@464: 				phase -= 2 * M_PI;
robert@464: 			float value = sinf(phase) * gVelocity/128.0f;
robert@464: 			audioWrite(context, n, 0, value);
robert@464: 			audioWrite(context, n, 1, value);
robert@464: 		} else {
robert@464: 			audioWrite(context, n, 0, 0);
robert@464: 			audioWrite(context, n, 1, 0);
robert@464: 		}
robert@464: 	}
robert@464: }
robert@464: 
robert@464: // cleanup() is called once at the end, after the audio has stopped.
robert@464: // Release any resources that were allocated in setup().
robert@464: 
robert@464: void cleanup(BelaContext *context, void *userData)
robert@464: {
robert@464: 
robert@464: }