comparison stk/src/SineWave.cpp @ 0:4606bd505630 tip

first import

+/***************************************************/
+/*! \class SineWave
+    \brief STK sinusoid oscillator class.
+
+    This class computes and saves a static sine "table" that can be
+    shared by multiple instances.  It has an interface similar to the
+    WaveLoop class but inherits from the Generator class.  Output
+    values are computed using linear interpolation.
+
+    The "table" length, set in SineWave.h, is 2048 samples by default.
+
+    by Perry R. Cook and Gary P. Scavone, 1995--2014.
+*/
+/***************************************************/
+
+#include "../include/SineWave.h"
+#include <cmath>
+
+namespace stk {
+
+StkFrames SineWave :: table_;
+
+SineWave :: SineWave( void )
+  : time_(0.0), rate_(1.0), phaseOffset_(0.0)
+{
+  if ( table_.empty() ) {
+    table_.resize( TABLE_SIZE + 1, 1 );
+    StkFloat temp = 1.0 / TABLE_SIZE;
+    for ( unsigned long i=0; i<=TABLE_SIZE; i++ )
+      table_[i] = sin( TWO_PI * i * temp );
+  }
+
+  Stk::addSampleRateAlert( this );
+}
+
+SineWave :: ~SineWave()
+{
+  Stk::removeSampleRateAlert( this );
+}
+
+void SineWave :: sampleRateChanged( StkFloat newRate, StkFloat oldRate )
+{
+  if ( !ignoreSampleRateChange_ )
+    this->setRate( oldRate * rate_ / newRate );
+}
+
+void SineWave :: reset( void )
+{
+  time_ = 0.0;
+  lastFrame_[0] = 0;
+}
+
+void SineWave :: setFrequency( StkFloat frequency )
+{
+  // This is a looping frequency.
+  this->setRate( TABLE_SIZE * frequency / Stk::sampleRate() );
+}
+
+void SineWave :: addTime( StkFloat time )
+{
+  // Add an absolute time in samples.
+  time_ += time;
+}
+
+void SineWave :: addPhase( StkFloat phase )
+{
+  // Add a time in cycles (one cycle = TABLE_SIZE).
+  time_ += TABLE_SIZE * phase;
+}
+
+void SineWave :: addPhaseOffset( StkFloat phaseOffset )
+{
+  // Add a phase offset relative to any previous offset value.
+  time_ += ( phaseOffset - phaseOffset_ ) * TABLE_SIZE;
+  phaseOffset_ = phaseOffset;
+}
+
+} // stk namespace