Version 4.4.0

src/TapDelay.cpp

@@ -0,0 +1,104 @@
+/***************************************************/
+/*! \class TapDelay
+    \brief STK non-interpolating tapped delay line class.
+
+    This class implements a non-interpolating digital delay-line with
+    an arbitrary number of output "taps".  If the maximum length and
+    tap delays are not specified during instantiation, a fixed maximum
+    length of 4095 and a single tap delay of zero is set.
+    
+    A non-interpolating delay line is typically used in fixed
+    delay-length applications, such as for reverberation.
+
+    by Perry R. Cook and Gary P. Scavone, 1995 - 2009.
+*/
+/***************************************************/
+
+#include "TapDelay.h"
+
+namespace stk {
+
+TapDelay :: TapDelay( std::vector<unsigned long> taps, unsigned long maxDelay )
+{
+  // Writing before reading allows delays from 0 to length-1. 
+  // If we want to allow a delay of maxDelay, we need a
+  // delayline of length = maxDelay+1.
+  if ( maxDelay < 1 ) {
+    errorString_ << "TapDelay::TapDelay: maxDelay must be > 0!\n";
+    handleError( StkError::FUNCTION_ARGUMENT );
+  }
+
+  for ( unsigned int i=0; i<taps.size(); i++ ) {
+    if ( taps[i] > maxDelay ) {
+      errorString_ << "TapDelay::TapDelay: maxDelay must be > than all tap delay values!\n";
+      handleError( StkError::FUNCTION_ARGUMENT );
+    }
+  }
+
+  if ( ( maxDelay + 1 ) > inputs_.size() )
+    inputs_.resize( maxDelay + 1, 1, 0.0 );
+
+  inPoint_ = 0;
+  this->setTapDelays( taps );
+}
+
+TapDelay :: ~TapDelay()
+{
+}
+
+void TapDelay :: setMaximumDelay( unsigned long delay )
+{
+  if ( delay < inputs_.size() ) return;
+
+  if ( delay < 0 ) {
+    errorString_ << "TapDelay::setMaximumDelay: argument (" << delay << ") less than zero!\n";
+    handleError( StkError::WARNING );
+    return;
+  }
+
+  for ( unsigned int i=0; i<delays_.size(); i++ ) {
+    if ( delay < delays_[i] ) {
+      errorString_ << "TapDelay::setMaximumDelay: argument (" << delay << ") less than a current tap delay setting (" << delays_[i] << ")!\n";
+      handleError( StkError::WARNING );
+      return;
+    }
+  }
+
+  inputs_.resize( delay + 1 );
+}
+
+void TapDelay :: setTapDelays( std::vector<unsigned long> taps )
+{
+  if ( taps.size() != outPoint_.size() ) {
+    outPoint_.resize( taps.size() );
+    delays_.resize( taps.size() );
+    lastFrame_.resize( 1, taps.size(), 0.0 );
+  }
+
+  for ( unsigned int i=0; i<taps.size(); i++ ) {
+    if ( taps[i] > inputs_.size() - 1 ) { // The value is too big.
+      errorString_ << "TapDelay::setTapDelay: argument (" << taps[i] << ") too big ... setting to maximum!\n";
+      handleError( StkError::WARNING );
+
+      // Force delay to maximum length.
+      outPoint_[i] = inPoint_ + 1;
+      if ( outPoint_[i] == inputs_.size() ) outPoint_[i] = 0;
+      delays_[i] = inputs_.size() - 1;
+    }
+    else if ( taps[i] < 0 ) {
+      errorString_ << "TapDelay::setDelay: argument (" << taps[i] << ") less than zero ... setting to zero!\n";
+      handleError( StkError::WARNING );
+
+      outPoint_[i] = inPoint_;
+      delays_[i] = 0;
+    }
+    else { // read chases write
+      if ( inPoint_ >= taps[i] ) outPoint_[i] = inPoint_ - taps[i];
+      else outPoint_[i] = inputs_.size() + inPoint_ - taps[i];
+      delays_[i] = taps[i];
+    }
+  }
+}
+
+} // stk namespace
+