Merge pull request #96 from pingdynasty/feature/synth-updates

Feature/synth updates

Author: pingdynasty

HISTORY.md

@@ -1,10 +1,16 @@
 v22.1
 -----
 
+* Added Sample oscillator
+* Added Agnesi curve oscillator
+* Added MPE processor
+* Added VOSIM oscillator
 * Added methods for sample-rate cutoff frequency modulation in StateVariableFilter and BiquadFilter
 * Added VelocityCurve, MidiProcessor, Synth and AbstractSynth
 * New templates for MIDI voicing: PolyphonicProcessor and MonophonicProcessor
 * Added WavFile for reading wav resources and converting to FloatArray
+* Changed enum for BUTTON_A, B, C to BUTTON_1, 2, 3 et c.
+* Fix FloatMatrix compilation
 
 v22.0
 -----

LibSource/AbstractSynth.h

@@ -22,7 +22,7 @@ class AbstractSynth : public Synth, public MidiProcessor, public VelocityCurve {
   /**
    * Set note in whole semitones and update frequency
    */
-  void setNote(uint8_t note){
+  virtual void setNote(uint8_t note){
     this->note = note;
     setFrequency(noteToFrequency(note+pb));
   }
@@ -35,7 +35,7 @@ class AbstractSynth : public Synth, public MidiProcessor, public VelocityCurve {
   /**
    * Set pitch bend amount in semitones and update frequency
    */
-  void setPitchBend(float pb){
+  virtual void setPitchBend(float pb){
     this->pb = pb;
     setFrequency(noteToFrequency(note+pb));
   }
@@ -53,25 +53,35 @@ class AbstractSynth : public Synth, public MidiProcessor, public VelocityCurve {
     this->pb_range = range;
   }  
   // MIDI handlers
-  virtual void noteOn(MidiMessage msg){
+  virtual void noteOn(MidiMessage msg) override {
     setNote(msg.getNote());
     setFrequency(noteToFrequency(note+pb));
     setGain(velocityToGain(msg.getVelocity()));
     gate(true);
   }
-  virtual void noteOff(MidiMessage msg){
+  virtual void noteOff(MidiMessage msg) override {
     gate(false);
   }
-  virtual void controlChange(MidiMessage msg){
-    if(msg.getControllerNumber() == MIDI_ALL_NOTES_OFF)
+  virtual void controlChange(MidiMessage msg) override {
+    if(msg.getControllerNumber() == MIDI_CC_MODULATION)
+      setModulation(msg.getControllerValue()/127.0f);
+    else if(msg.getControllerNumber() == MIDI_ALL_NOTES_OFF)
       allNotesOff();
   }
-  virtual void allNotesOff(){
-    gate(false);
+  virtual void channelPressure(MidiMessage msg) override {
+    setPressure(msg.getChannelPressure()/127.0f);
+  }
+  virtual void polyKeyPressure(MidiMessage msg) override {
+    setPressure(msg.getPolyKeyPressure()/127.0f);
   }
-  virtual void pitchbend(MidiMessage msg){
+  virtual void setModulation(float modulation){} // default implementation does nothing
+  virtual void setPressure(float pressure){}
+  virtual void pitchbend(MidiMessage msg) override {
     setPitchBend(pb_range*msg.getPitchBend()/8192.0f);
   }
+  virtual void allNotesOff(){
+    gate(false);
+  }
   // static utility methods
   static inline float frequencyToNote(float freq){
     return 12 * log2f(freq / 440) + 69;
@@ -80,154 +90,5 @@ class AbstractSynth : public Synth, public MidiProcessor, public VelocityCurve {
     return 440 * exp2f((note - 69) / 12);
   }
 };
-  
-template<class SynthVoice, int VOICES>
-class PolyphonicProcessor : public MidiProcessor {
-private:
-  static const uint16_t TAKEN = 0xffff;
-  SynthVoice* voice[VOICES];
-  uint8_t notes[VOICES];
-  uint16_t allocation[VOICES];
-  uint16_t allocated;
-  FloatArray buffer;
-protected:
-  void take(uint8_t ch, MidiMessage msg){
-    release(ch);
-    notes[ch] = msg.getNote();
-    allocation[ch] = TAKEN;
-    voice[ch]->noteOn(msg);
-  }
-  void release(uint8_t ch){
-    allocation[ch] = ++allocated;
-    voice[ch]->gate(false);
-  }
-public:
-  PolyphonicProcessor(FloatArray buffer) : allocated(0), buffer(buffer) {}
-  virtual ~PolyphonicProcessor(){};
-  static PolyphonicProcessor<SynthVoice, VOICES>* create(size_t blocksize){
-    FloatArray buffer = FloatArray::create(blocksize);    
-    return new PolyphonicProcessor<SynthVoice, VOICES>(buffer);
-  }
-  static void destroy(PolyphonicProcessor<SynthVoice, VOICES>* obj){
-    delete obj->buffer;
-    delete obj;
-  }
-  void noteOn(MidiMessage msg){
-    uint8_t note = msg.getNote();
-    uint16_t minval = USHRT_MAX;
-    uint8_t minidx = 0;
-    // take oldest free voice, to allow voices to ring out
-    for(int i=0; i<VOICES; ++i){
-      if(notes[i] == note){
-	minidx = i;
-	break;
-      }
-      if(allocation[i] < minval){
-	minidx = i;
-	minval = allocation[i];
-      }
-    }
-    // take oldest voice
-    take(minidx, msg);
-  }
-  void noteOff(MidiMessage msg){
-    uint8_t note = msg.getNote();
-    for(int i=0; i<VOICES; ++i)
-      if(notes[i] == note)
-	release(i);
-  }
-  float generate(){
-    float sample = 0.0f;
-    for(int i=0; i<VOICES; ++i)
-      sample += voice[i]->generate();
-    return sample;
-  }
-  void generate(FloatArray output){
-    voice[0]->generate(output);
-    for(int i=1; i<VOICES; ++i){
-      voice[i]->generate(buffer);
-      output.add(buffer);
-    }
-  }
- void controlChange(MidiMessage msg){
-    if(msg.getControllerNumber() == MIDI_ALL_NOTES_OFF)
-      allNotesOff();
-  }
-  void pitchbend(MidiMessage msg){
-    for(int i=0; i<VOICES; ++i)
-      voice[i]->pitchbend(msg);
-  }
-  void allNotesOn() {
-    for(int i=0; i<VOICES; ++i)
-      voice[i]->gate(true);      
-  }
-  void allNotesOff() {
-    for(int i=0; i<VOICES; ++i)
-      voice[i]->gate(false);      
-  }
-  void setVoice(size_t index, SynthVoice* obj){
-    if(index < VOICES)
-      voice[index] = obj;
-  }
-  SynthVoice* getVoice(size_t index){
-    if(index < VOICES)
-      return voice[index];
-    return NULL;
-  }
-};
-
-template<class SynthVoice>
-class MonophonicProcessor : public MidiProcessor {
-private:
-  SynthVoice* voice;
-  uint8_t notes[16];
-  uint8_t lastNote = 0;
-public:
-  MonophonicProcessor(SynthVoice* voice) : voice(voice) {}
-  virtual void noteOn(MidiMessage msg){
-    if(lastNote < 16)
-      notes[lastNote++] = msg.getNote();
-    voice->noteOn(msg);
-  }
-  virtual void noteOff(MidiMessage msg){
-    uint8_t note = msg.getNote();
-    int i;
-    for(i = 0; i < lastNote; ++i) {
-      if(notes[i] == note)
-	break;
-    }
-    if(lastNote > 1) {
-      lastNote--;
-      while (i < lastNote) {
-	notes[i] = notes[i + 1];
-	i++;
-      }
-      voice->setNote(notes[lastNote - 1]);
-    }else{
-      voice->gate(false);
-      lastNote = 0;
-    }
-  }
-  void allNotesOff() {
-    voice->gate(false);
-    lastNote = 0;
-  }
-  float generate(){
-    return voice->generate();
-  }
-  void generate(FloatArray output){
-    voice->generate(output);
-  }
- void controlChange(MidiMessage msg){
-    if(msg.getControllerNumber() == MIDI_ALL_NOTES_OFF)
-      allNotesOff();
-  }
-  void pitchbend(MidiMessage msg){
-    voice->pitchbend(msg);
-  }
-  SynthVoice* getVoice(){
-    return voice;
-  }
-};
 
 #endif // __AbstractSynth_h__

LibSource/AgnesiOscillator.h

@@ -0,0 +1,71 @@
+#ifndef __AgnesiOscillator_h
+#define __AgnesiOscillator_h
+
+#include "Oscillator.h"
+
+/**
+ * Oscillator that produces an Agnesi curve (Witch of Agnesi)
+ * With a=0.5, the output is between near 0 (0.038 for N=5) and 1.
+ * N sets the x range for one half period, which determines the y offset.
+ */
+class AgnesiOscillator : public Oscillator {
+private:
+  const float sr;
+  float a;
+  float N;
+  float incr = 0;
+  float x = 0;
+  float offset = 0;
+  float gain = 1;
+public:
+  AgnesiOscillator(float sr, float a, float N)
+    : sr(sr), a(a), N(N) {}
+  static float agnesi(float x, float a){
+    return (8*a*a*a) / (x*x + 4*a*a);
+  }
+  void setFrequency(float freq){
+    incr = 2*N*freq/sr;
+  }
+  float getFrequency(){
+    return incr*sr/(2*N);
+  }
+  void setPhase(float phase){
+    x = N*(phase-M_PI)/M_PI;
+  }
+  float getPhase(){
+    return M_PI*x/N+M_PI;
+  }
+  /**
+   * Normalise offset and gain so that signal is between 0 and 1
+   */
+  void normalise(){
+    offset = agnesi(N, a);
+    gain = 1/(agnesi(0, a) - offset);
+  }
+  float generate(){
+    float y = agnesi(x, a);
+    x += incr;
+    if(x > N)
+      x -= 2*N;
+    return gain*(y-offset);
+  }
+  float generate(float fm){
+    // modulate coefficient 'a' instead of rate
+    float y = agnesi(x, a+fm);
+    x += incr;
+    if(x > N)
+      x -= 2*N;
+    return gain*(y-offset);
+  }
+  using SignalGenerator::generate;
+  static AgnesiOscillator* create(float sr, float a=0.5, float N=5){
+    AgnesiOscillator* osc = new AgnesiOscillator(sr, a, N);
+    osc->normalise();
+    return osc;
+  }
+  static void destroy(AgnesiOscillator* obj){
+    delete obj;
+  }
+};
+
+#endif /* __AgnesiOscillator_h */

LibSource/AudioBuffer.h

@@ -0,0 +1,18 @@
+#ifndef __AudioBuffer_h__
+#define __AudioBuffer_h__
+
+#include "FloatArray.h"
+
+class AudioBuffer {
+public:
+  virtual ~AudioBuffer();
+  virtual FloatArray getSamples(int channel) = 0;
+  virtual int getChannels() = 0;
+  virtual int getSize() = 0;
+  virtual void clear() = 0;
+  virtual void add(AudioBuffer& buffer) = 0;
+  static AudioBuffer* create(int channels, int samples);
+  static void destroy(AudioBuffer* buffer);
+};
+
+#endif // __AudioBuffer_h__