Version 4.4.0

src/NRev.cpp

@@ -2,43 +2,45 @@
 /*! \class NRev
     \brief CCRMA's NRev reverberator class.
 
-    This class is derived from the CLM NRev
-    function, which is based on the use of
-    networks of simple allpass and comb delay
-    filters.  This particular arrangement consists
-    of 6 comb filters in parallel, followed by 3
-    allpass filters, a lowpass filter, and another
-    allpass in series, followed by two allpass
-    filters in parallel with corresponding right
-    and left outputs.
+    This class takes a monophonic input signal and produces a stereo
+    output signal.  It is derived from the CLM NRev function, which is
+    based on the use of networks of simple allpass and comb delay
+    filters.  This particular arrangement consists of 6 comb filters
+    in parallel, followed by 3 allpass filters, a lowpass filter, and
+    another allpass in series, followed by two allpass filters in
+    parallel with corresponding right and left outputs.
 
-    by Perry R. Cook and Gary P. Scavone, 1995 - 2007.
+    by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
 */
 /***************************************************/
 
 #include "NRev.h"
-#include <math.h>
+#include <cmath>
 
-NRev :: NRev(StkFloat T60)
+namespace stk {
+
+NRev :: NRev( StkFloat T60 )
 {
+  lastFrame_.resize( 1, 2, 0.0 ); // resize lastFrame_ for stereo output
+
   int lengths[15] = {1433, 1601, 1867, 2053, 2251, 2399, 347, 113, 37, 59, 53, 43, 37, 29, 19};
   double scaler = Stk::sampleRate() / 25641.0;
 
   int delay, i;
-  for (i=0; i<15; i++) {
+  for ( i=0; i<15; i++ ) {
     delay = (int) floor(scaler * lengths[i]);
     if ( (delay & 1) == 0) delay++;
     while ( !this->isPrime(delay) ) delay += 2;
     lengths[i] = delay;
   }
 
-  for (i=0; i<6; i++) {
+  for ( i=0; i<6; i++ ) {
     combDelays_[i].setMaximumDelay( lengths[i] );
     combDelays_[i].setDelay( lengths[i] );
     combCoefficient_[i] = pow(10.0, (-3 * lengths[i] / (T60 * Stk::sampleRate())));
   }
 
-  for (i=0; i<8; i++) {
+  for ( i=0; i<8; i++ ) {
 	  allpassDelays_[i].setMaximumDelay( lengths[i+6] );
 	  allpassDelays_[i].setDelay( lengths[i+6] );
   }
@@ -49,17 +51,13 @@ NRev :: NRev(StkFloat T60)
   this->clear();
 }
 
-NRev :: ~NRev()
-{
-}
-
 void NRev :: clear()
 {
   int i;
   for (i=0; i<6; i++) combDelays_[i].clear();
   for (i=0; i<8; i++) allpassDelays_[i].clear();
-  lastOutput_[0] = 0.0;
-  lastOutput_[1] = 0.0;
+  lastFrame_[0] = 0.0;
+  lastFrame_[1] = 0.0;
   lowpassState_ = 0.0;
 }
 
@@ -69,47 +67,44 @@ void NRev :: setT60( StkFloat T60 )
     combCoefficient_[i] = pow(10.0, (-3.0 * combDelays_[i].getDelay() / (T60 * Stk::sampleRate())));
 }
 
-StkFloat NRev :: computeSample(StkFloat input)
+StkFrames& NRev :: tick( StkFrames& frames, unsigned int channel )
 {
-  StkFloat temp, temp0, temp1, temp2, temp3;
-  int i;
-
-  temp0 = 0.0;
-  for (i=0; i<6; i++) {
-    temp = input + (combCoefficient_[i] * combDelays_[i].lastOut());
-    temp0 += combDelays_[i].tick(temp);
+#if defined(_STK_DEBUG_)
+  if ( channel >= frames.channels() - 1 ) {
+    errorString_ << "NRev::tick(): channel and StkFrames arguments are incompatible!";
+    handleError( StkError::FUNCTION_ARGUMENT );
   }
-  for (i=0; i<3; i++)	{
-    temp = allpassDelays_[i].lastOut();
-    temp1 = allpassCoefficient_ * temp;
-    temp1 += temp0;
-    allpassDelays_[i].tick(temp1);
-    temp0 = -(allpassCoefficient_ * temp1) + temp;
+#endif
+
+  StkFloat *samples = &frames[channel];
+  unsigned int hop = frames.channels();
+  for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
+    *samples = tick( *samples );
+    samples++;
+    *samples = lastFrame_[1];
   }
 
-	// One-pole lowpass filter.
-  lowpassState_ = 0.7*lowpassState_ + 0.3*temp0;
-  temp = allpassDelays_[3].lastOut();
-  temp1 = allpassCoefficient_ * temp;
-  temp1 += lowpassState_;
-  allpassDelays_[3].tick(temp1);
-  temp1 = -(allpassCoefficient_ * temp1) + temp;
-    
-  temp = allpassDelays_[4].lastOut();
-  temp2 = allpassCoefficient_ * temp;
-  temp2 += temp1;
-  allpassDelays_[4].tick(temp2);
-  lastOutput_[0] = effectMix_*(-(allpassCoefficient_ * temp2) + temp);
-    
-  temp = allpassDelays_[5].lastOut();
-  temp3 = allpassCoefficient_ * temp;
-  temp3 += temp1;
-  allpassDelays_[5].tick(temp3);
-  lastOutput_[1] = effectMix_*(-(allpassCoefficient_ * temp3) + temp);
-
-  temp = (1.0 - effectMix_) * input;
-  lastOutput_[0] += temp;
-  lastOutput_[1] += temp;
-    
-  return Effect::lastOut();
+  return frames;
 }
+
+StkFrames& NRev :: tick( StkFrames& iFrames, StkFrames& oFrames, unsigned int iChannel, unsigned int oChannel )
+{
+#if defined(_STK_DEBUG_)
+  if ( iChannel >= iFrames.channels() || oChannel >= oFrames.channels() - 1 ) {
+    errorString_ << "NRev::tick(): channel and StkFrames arguments are incompatible!";
+    handleError( StkError::FUNCTION_ARGUMENT );
+  }
+#endif
+
+  StkFloat *iSamples = &iFrames[iChannel];
+  StkFloat *oSamples = &oFrames[oChannel];
+  unsigned int iHop = iFrames.channels(), oHop = oFrames.channels();
+  for ( unsigned int i=0; i<iFrames.frames(); i++, iSamples += iHop, oSamples += oHop ) {
+    *oSamples++ = tick( *iSamples );
+    *oSamples = lastFrame_[1];
+  }
+
+  return iFrames;
+}
+
+} // stk namespace