comparison layer/SpectrogramLayer.h @ 133:9e6b3e239b9d

* Add zoom thumbwheels to Pane.  Implement horizontal thumbwheel, and
  vertical depending on layer type (supported for waveform and spectrogram,
  though wrong for log-scale spectrogram at the moment).
* Add bare bones of a spectrum layer.
* Add window icon
* Add shortcut for "insert time instant" on laptops without keypad enter (";")
* Delete FFT processing thread when it exits (at least, next time we're asked
  for something interesting)
* Get audio file extensions from the file readers, and thus from libsndfile for
  the wave file reader -- leads to rather a wide combo box in file dialog though
* Better refresh order for spectrogram (redraw centre section first)

     void setProperties(const QXmlAttributes &attributes);
 
     virtual void setLayerDormant(const View *v, bool dormant);
 
     virtual bool isLayerScrollable(const View *v) const { return false; }
+
+    virtual int getVerticalZoomSteps(int &defaultStep) const;
+    virtual int getCurrentVerticalZoomStep() const;
+    virtual void setVerticalZoomStep(int);
 
 protected slots:
     void cacheInvalid();
     void cacheInvalid(size_t startFrame, size_t endFrame);
     

     QColor              m_crosshairColour;
     FrequencyScale      m_frequencyScale;
     BinDisplay          m_binDisplay;
     bool                m_normalizeColumns;
     bool                m_normalizeVisibleArea;
+    int                 m_lastEmittedZoomStep;
 
     enum { NO_VALUE = 0 }; // colour index for unused pixels
 
     class ColourMap
     {