Version 4.4.0

include/PitShift.h

@@ -1,3 +1,11 @@
+#ifndef STK_PITSHIFT_H
+#define STK_PITSHIFT_H
+
+#include "Effect.h"
+#include "DelayL.h"
+
+namespace stk {
+
 /***************************************************/
 /*! \class PitShift
     \brief STK simple pitch shifter effect class.
@@ -5,43 +13,95 @@
     This class implements a simple pitch shifter
     using delay lines.
 
-    by Perry R. Cook and Gary P. Scavone, 1995 - 2007.
+    by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
 */
 /***************************************************/
 
-#ifndef STK_PITSHIFT_H
-#define STK_PITSHIFT_H
-
-#include "Effect.h" 
-#include "DelayL.h" 
+const int maxDelay = 5024;
 
 class PitShift : public Effect
 {
  public:
   //! Class constructor.
-  PitShift();
-
-  //! Class destructor.
-  ~PitShift();
+  PitShift( void );
 
   //! Reset and clear all internal state.
-  void clear();
+  void clear( void );
 
   //! Set the pitch shift factor (1.0 produces no shift).
-  void setShift(StkFloat shift);
+  void setShift( StkFloat shift );
+
+  //! Return the last computed output value.
+  StkFloat lastOut( void ) const { return lastFrame_[0]; };
+
+  //! Input one sample to the effect and return one output.
+  StkFloat tick( StkFloat input );
+
+  //! Take a channel of the StkFrames object as inputs to the effect and replace with corresponding outputs.
+  /*!
+    The StkFrames argument reference is returned.  The \c channel
+    argument must be less than the number of channels in the
+    StkFrames argument (the first channel is specified by 0).
+    However, range checking is only performed if _STK_DEBUG_ is
+    defined during compilation, in which case an out-of-range value
+    will trigger an StkError exception.
+  */
+  StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
+
+  //! Take a channel of the \c iFrames object as inputs to the effect and write outputs to the \c oFrames object.
+  /*!
+    The \c iFrames object reference is returned.  Each channel
+    argument must be less than the number of channels in the
+    corresponding StkFrames argument (the first channel is specified
+    by 0).  However, range checking is only performed if _STK_DEBUG_
+    is defined during compilation, in which case an out-of-range value
+    will trigger an StkError exception.
+  */
+  StkFrames& tick( StkFrames& iFrames, StkFrames &oFrames, unsigned int iChannel = 0, unsigned int oChannel = 0 );
 
  protected:
 
-  StkFloat computeSample( StkFloat input );
-
   DelayL delayLine_[2];
   StkFloat delay_[2];
   StkFloat env_[2];
   StkFloat rate_;
-  unsigned long delayLength;
-  unsigned long halfLength;
+  unsigned long delayLength_;
+  unsigned long halfLength_;
 
 };
 
+inline StkFloat PitShift :: tick( StkFloat input )
+{
+  // Calculate the two delay length values, keeping them within the
+  // range 12 to maxDelay-12.
+  delay_[0] += rate_;
+  while ( delay_[0] > maxDelay-12 ) delay_[0] -= delayLength_;
+  while ( delay_[0] < 12 ) delay_[0] += delayLength_;
+
+  delay_[1] = delay_[0] + halfLength_;
+  while ( delay_[1] > maxDelay-12 ) delay_[1] -= delayLength_;
+  while ( delay_[1] < 12 ) delay_[1] += delayLength_;
+
+  // Set the new delay line lengths.
+  delayLine_[0].setDelay( delay_[0] );
+  delayLine_[1].setDelay( delay_[1] );
+
+  // Calculate a triangular envelope.
+  env_[1] = fabs( ( delay_[0] - halfLength_ + 12 ) * ( 1.0 / (halfLength_ + 12 ) ) );
+  env_[0] = 1.0 - env_[1];
+
+  // Delay input and apply envelope.
+  lastFrame_[0] =  env_[0] * delayLine_[0].tick( input );
+  lastFrame_[0] += env_[1] * delayLine_[1].tick( input );
+
+  // Compute effect mix and output.
+  lastFrame_[0] *= effectMix_;
+  lastFrame_[0] += ( 1.0 - effectMix_ ) * input;
+
+  return lastFrame_[0];
+}
+
+} // stk namespace
+
 #endif