AsyncAudioDelayLine.h

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#ifndef ASYNC_AUDIO_DELAY_LINE_INCLUDED
#define ASYNC_AUDIO_DELAY_LINE_INCLUDED
 
 
/****************************************************************************
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 * System Includes
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/****************************************************************************
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 * Project Includes
 *
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#include <AsyncAudioSink.h>
#include <AsyncAudioSource.h>
 
 
/****************************************************************************
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 * Local Includes
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/****************************************************************************
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 * Forward declarations
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/****************************************************************************
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 * Namespace
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namespace Async
{
 
 
/****************************************************************************
 *
 * Forward declarations of classes inside of the declared namespace
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/****************************************************************************
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 * Defines & typedefs
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/****************************************************************************
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 * Exported Global Variables
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/****************************************************************************
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 * Class definitions
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class AudioDelayLine : public Async::AudioSink, public Async::AudioSource
{
  public:
    explicit AudioDelayLine(int length_ms);
  
    ~AudioDelayLine(void);
 
    void setFadeTime(int time_ms);
    
    void mute(bool do_mute, int time_ms=0);
    
    void clear(int time_ms=-1);
  
    int writeSamples(const float *samples, int count);
    
    void flushSamples(void);
 
    void resumeOutput(void);
    
    void allSamplesFlushed(void);
    
    
  protected:
    
  private:
    static const int DEFAULT_FADE_TIME = 10; // 10ms default fade time
 
    float       *buf;
    int         size;
    int         ptr;
    int         flush_cnt;
    bool        is_muted;
    int         mute_cnt;
    int         last_clear;
    float       *fade_gain;
    int         fade_len;
    int         fade_pos;
    int         fade_dir;
    
    AudioDelayLine(const AudioDelayLine&);
    AudioDelayLine& operator=(const AudioDelayLine&);
    void writeRemainingSamples(void);
 
    inline float currentFadeGain(void)
    {
      if (fade_gain == 0)
      {
        return 1.0f;
      }
      
      float gain = fade_gain[fade_pos];
      fade_pos += fade_dir;
      
      if ((fade_dir > 0) && (fade_pos >= fade_len-1))
      {
        fade_dir = 0;
        fade_pos = fade_len-1;
      }
      else if ((fade_dir < 0) && (fade_pos <= 0))
      {
        fade_dir = 0;
        fade_pos = 0;
      }
      
      return gain;
      
    } /* AudioDelayLine::currentFadeGain  */
 
};  /* class AudioDelayLine */
 
 
} /* namespace */
 
#endif /* ASYNC_AUDIO_DELAY_LINE_INCLUDED */
 
 
 
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