SampleTrack.h

Go to the documentation of this file.

/**********************************************************************
 
Audacity: A Digital Audio Editor
 
SampleTrack.h
@brief abstract Track sub-type that maps times to sample values
 
Paul Licameli split from WaveTrack.h
 
**********************************************************************/
 
#ifndef __AUDACITY_SAMPLE_TRACK__
#define __AUDACITY_SAMPLE_TRACK__
 
#include "SampleCount.h"
#include "SampleFormat.h"
#include "Track.h"
 
class SAMPLE_TRACK_API SampleTrack /* not final */
   : public PlayableTrack
{
public:
   ~SampleTrack() override;
 
   const TypeInfo &GetTypeInfo() const override;
   static const TypeInfo &ClassTypeInfo();
 
   virtual sampleFormat GetSampleFormat() const = 0;
 
   virtual ChannelType GetChannelIgnoringPan() const = 0;
 
   // Old gain is used in playback in linearly interpolating
   // the gain.
   virtual float GetOldChannelGain(int channel) const = 0;
 
   virtual double GetRate() const = 0;
 
   virtual void GetEnvelopeValues(double *buffer, size_t bufferLen,
                         double t0) const = 0;
 
   virtual float GetChannelGain(int channel) const = 0;
 
   virtual size_t GetBestBlockSize(sampleCount t) const = 0;
 
   virtual size_t GetMaxBlockSize() const = 0;
 
   virtual sampleCount GetBlockStart(sampleCount t) const = 0;
 
 
   bool GetFloats(float *buffer, sampleCount start, size_t len,
      fillFormat fill = fillZero, bool mayThrow = true,
      sampleCount * pNumWithinClips = nullptr) const
   {
      return Get(reinterpret_cast<samplePtr>(buffer),
         floatSample, start, len, fill, mayThrow, pNumWithinClips);
   }
 
 
   virtual bool Get(samplePtr buffer, sampleFormat format,
      sampleCount start, size_t len,
      fillFormat fill = fillZero,
      bool mayThrow = true,
      // Report how many samples were copied from within clips, rather than
      // filled according to fillFormat; but these were not necessarily one
      // contiguous range.
      sampleCount * pNumWithinClips = nullptr) const = 0;
 
   sampleCount TimeToLongSamples(double t0) const;
   double LongSamplesToTime(sampleCount pos) const;
};
 
ENUMERATE_TRACK_TYPE(SampleTrack)
 
class SAMPLE_TRACK_API WritableSampleTrack /* not final */
   : public SampleTrack
{
public:
   ~WritableSampleTrack() override;
 
   const TypeInfo &GetTypeInfo() const override;
   static const TypeInfo &ClassTypeInfo();
 
   virtual void SetOldChannelGain(int channel, float gain) = 0;
 
   virtual bool Append(constSamplePtr buffer, sampleFormat format,
               size_t len, unsigned int stride=1) = 0;
 
   virtual void Flush() = 0;
};
 
ENUMERATE_TRACK_TYPE(WritableSampleTrack)
 
#endif