Version 4.0

src/Resonate.cpp

@@ -0,0 +1,150 @@
+/***************************************************/
+/*! \class Resonate
+    \brief STK noise driven formant filter.
+
+    This instrument contains a noise source, which
+    excites a biquad resonance filter, with volume
+    controlled by an ADSR.
+
+    Control Change Numbers:
+       - Resonance Frequency (0-Nyquist) = 2
+       - Pole Radii = 4
+       - Notch Frequency (0-Nyquist) = 11
+       - Zero Radii = 1
+       - Envelope Gain = 128
+
+    by Perry R. Cook and Gary P. Scavone, 1995 - 2002.
+*/
+/***************************************************/
+
+#include "Resonate.h"
+#include "SKINI.msg"
+
+Resonate :: Resonate()
+{
+  adsr = new ADSR;
+  noise = new Noise;
+
+  filter = new BiQuad;
+  poleFrequency = 4000.0;
+  poleRadius = 0.95;
+  // Set the filter parameters.
+  filter->setResonance( poleFrequency, poleRadius, TRUE );
+  zeroFrequency = 0.0;
+  zeroRadius = 0.0;
+}  
+
+Resonate :: ~Resonate()
+{
+  delete adsr;
+  delete filter;
+  delete noise;
+}
+
+void Resonate :: keyOn()
+{
+  adsr->keyOn();
+}
+
+void Resonate :: keyOff()
+{
+  adsr->keyOff();
+}
+
+void Resonate :: noteOn(MY_FLOAT frequency, MY_FLOAT amplitude)
+{
+  adsr->setTarget( amplitude );
+  this->keyOn();
+  this->setResonance(frequency, poleRadius);
+
+#if defined(_STK_DEBUG_)
+  cerr << "Resonate: NoteOn frequency = " << frequency << ", amplitude = " << amplitude << endl;
+#endif
+}
+void Resonate :: noteOff(MY_FLOAT amplitude)
+{
+  this->keyOff();
+
+#if defined(_STK_DEBUG_)
+  cerr << "Resonate: NoteOff amplitude = " << amplitude << endl;
+#endif
+}
+
+void Resonate :: setResonance(MY_FLOAT frequency, MY_FLOAT radius)
+{
+  poleFrequency = frequency;
+  if ( frequency < 0.0 ) {
+    cerr << "Resonate: setResonance frequency parameter is less than zero!" << endl;
+    poleFrequency = 0.0;
+  }
+
+  poleRadius = radius;
+  if ( radius < 0.0 ) {
+    cerr << "Resonate: setResonance radius parameter is less than 0.0!" << endl;
+    poleRadius = 0.0;
+  }
+  else if ( radius >= 1.0 ) {
+    cerr << "Resonate: setResonance radius parameter is greater than or equal to 1.0, which is unstable!" << endl;
+    poleRadius = 0.9999;
+  }
+  filter->setResonance( poleFrequency, poleRadius, TRUE );
+}
+
+void Resonate :: setNotch(MY_FLOAT frequency, MY_FLOAT radius)
+{
+  zeroFrequency = frequency;
+  if ( frequency < 0.0 ) {
+    cerr << "Resonate: setNotch frequency parameter is less than zero!" << endl;
+    zeroFrequency = 0.0;
+  }
+
+  zeroRadius = radius;
+  if ( radius < 0.0 ) {
+    cerr << "Resonate: setNotch radius parameter is less than 0.0!" << endl;
+    zeroRadius = 0.0;
+  }
+  
+  filter->setNotch( zeroFrequency, zeroRadius );
+}
+
+void Resonate :: setEqualGainZeroes()
+{
+  filter->setEqualGainZeroes();
+}
+
+MY_FLOAT Resonate :: tick()
+{
+  lastOutput = filter->tick(noise->tick());
+  lastOutput *= adsr->tick();
+  return lastOutput;
+}
+
+void Resonate :: controlChange(int number, MY_FLOAT value)
+{
+  MY_FLOAT norm = value * ONE_OVER_128;
+  if ( norm < 0 ) {
+    norm = 0.0;
+    cerr << "Resonate: Control value less than zero!" << endl;
+  }
+  else if ( norm > 1.0 ) {
+    norm = 1.0;
+    cerr << "Resonate: Control value greater than 128.0!" << endl;
+  }
+
+  if (number == 2) // 2
+    setResonance( norm * Stk::sampleRate() * 0.5, poleRadius );
+  else if (number == 4) // 4
+    setResonance( poleFrequency, norm*0.9999 );
+  else if (number == 11) // 11
+    this->setNotch( norm * Stk::sampleRate() * 0.5, zeroRadius );
+  else if (number == 1)
+    this->setNotch( zeroFrequency, norm );
+  else if (number == __SK_AfterTouch_Cont_) // 128
+    adsr->setTarget( norm );
+  else
+    cerr << "Resonate: Undefined Control Number (" << number << ")!!" << endl;
+
+#if defined(_STK_DEBUG_)
+  cerr << "Resonate: controlChange number = " << number << ", value = " << value << endl;
+#endif
+}