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DelayL.h

00001 #ifndef STK_DELAYL_H
00002 #define STK_DELAYL_H
00003 
00004 #include "Delay.h"
00005 
00006 namespace stk {
00007 
00008 /***************************************************/
00025 /***************************************************/
00026 
00027 class DelayL : public Filter
00028 {
00029 public:
00030 
00032 
00037   DelayL( StkFloat delay = 0.0, unsigned long maxDelay = 4095 );
00038 
00040   ~DelayL();
00041 
00043   unsigned long getMaximumDelay( void ) { return inputs_.size() - 1; };
00044 
00046 
00053   void setMaximumDelay( unsigned long delay );
00054 
00056 
00059   void setDelay( StkFloat delay );
00060 
00062   StkFloat getDelay( void ) const { return delay_; };
00063 
00065 
00070   StkFloat tapOut( unsigned long tapDelay );
00071 
00073   void tapIn( StkFloat value, unsigned long tapDelay );
00074 
00076   StkFloat lastOut( void ) const { return lastFrame_[0]; };
00077 
00079 
00082   StkFloat nextOut( void );
00083 
00085   StkFloat tick( StkFloat input );
00086 
00088 
00096   StkFrames& tick( StkFrames& frames, unsigned int channel = 0 );
00097 
00099 
00107   StkFrames& tick( StkFrames& iFrames, StkFrames &oFrames, unsigned int iChannel = 0, unsigned int oChannel = 0 );
00108 
00109  protected:
00110 
00111   unsigned long inPoint_;
00112   unsigned long outPoint_;
00113   StkFloat delay_;
00114   StkFloat alpha_;
00115   StkFloat omAlpha_;
00116   StkFloat nextOutput_;
00117   bool doNextOut_;
00118 };
00119 
00120 inline StkFloat DelayL :: nextOut( void )
00121 {
00122   if ( doNextOut_ ) {
00123     // First 1/2 of interpolation
00124     nextOutput_ = inputs_[outPoint_] * omAlpha_;
00125     // Second 1/2 of interpolation
00126     if (outPoint_+1 < inputs_.size())
00127       nextOutput_ += inputs_[outPoint_+1] * alpha_;
00128     else
00129       nextOutput_ += inputs_[0] * alpha_;
00130     doNextOut_ = false;
00131   }
00132 
00133   return nextOutput_;
00134 }
00135 
00136 inline StkFloat DelayL :: tick( StkFloat input )
00137 {
00138   inputs_[inPoint_++] = input * gain_;
00139 
00140   // Increment input pointer modulo length.
00141   if ( inPoint_ == inputs_.size() )
00142     inPoint_ = 0;
00143 
00144   lastFrame_[0] = nextOut();
00145   doNextOut_ = true;
00146 
00147   // Increment output pointer modulo length.
00148   if ( ++outPoint_ == inputs_.size() )
00149     outPoint_ = 0;
00150 
00151   return lastFrame_[0];
00152 }
00153 
00154 inline StkFrames& DelayL :: tick( StkFrames& frames, unsigned int channel )
00155 {
00156 #if defined(_STK_DEBUG_)
00157   if ( channel >= frames.channels() ) {
00158     oStream_ << "DelayL::tick(): channel and StkFrames arguments are incompatible!";
00159     handleError( StkError::FUNCTION_ARGUMENT );
00160   }
00161 #endif
00162 
00163   StkFloat *samples = &frames[channel];
00164   unsigned int hop = frames.channels();
00165   for ( unsigned int i=0; i<frames.frames(); i++, samples += hop ) {
00166     inputs_[inPoint_++] = *samples * gain_;
00167     if ( inPoint_ == inputs_.size() ) inPoint_ = 0;
00168     *samples = nextOut();
00169     doNextOut_ = true;
00170     if ( ++outPoint_ == inputs_.size() ) outPoint_ = 0;
00171   }
00172 
00173   lastFrame_[0] = *(samples-hop);
00174   return frames;
00175 }
00176 
00177 inline StkFrames& DelayL :: tick( StkFrames& iFrames, StkFrames& oFrames, unsigned int iChannel, unsigned int oChannel )
00178 {
00179 #if defined(_STK_DEBUG_)
00180   if ( iChannel >= iFrames.channels() || oChannel >= oFrames.channels() ) {
00181     oStream_ << "DelayL::tick(): channel and StkFrames arguments are incompatible!";
00182     handleError( StkError::FUNCTION_ARGUMENT );
00183   }
00184 #endif
00185 
00186   StkFloat *iSamples = &iFrames[iChannel];
00187   StkFloat *oSamples = &oFrames[oChannel];
00188   unsigned int iHop = iFrames.channels(), oHop = oFrames.channels();
00189   for ( unsigned int i=0; i<iFrames.frames(); i++, iSamples += iHop, oSamples += oHop ) {
00190     inputs_[inPoint_++] = *iSamples * gain_;
00191     if ( inPoint_ == inputs_.size() ) inPoint_ = 0;
00192     *oSamples = nextOut();
00193     doNextOut_ = true;
00194     if ( ++outPoint_ == inputs_.size() ) outPoint_ = 0;
00195   }
00196 
00197   lastFrame_[0] = *(oSamples-oHop);
00198   return iFrames;
00199 }
00200 
00201 } // stk namespace
00202 
00203 #endif

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