Move class ZoomInfo to separate files

src/ZoomInfo.h

@@ -0,0 +1,142 @@
+/**********************************************************************
+
+  Audacity: A Digital Audio Editor
+
+  ZoomInfo.h
+
+  Paul Licameli split from ViewInfo.h
+
+**********************************************************************/
+
+#ifndef __AUDACITY_ZOOM_INFO__
+#define __AUDACITY_ZOOM_INFO__
+
+#include "ClientData.h" // to inherit
+#include "Prefs.h" // to inherit
+
+#ifdef __GNUC__
+#define CONST
+#else
+#define CONST const
+#endif
+
+class AudacityProject;
+
+// The subset of ViewInfo information (other than selection)
+// that is sufficient for purposes of TrackArtist,
+// and for computing conversions between track times and pixel positions.
+class AUDACITY_DLL_API ZoomInfo /* not final */
+   // Note that ViewInfo inherits from ZoomInfo but there are no virtual functions.
+   // That's okay if we pass always by reference and never copy, suffering "slicing."
+   : public ClientData::Base
+   , protected PrefsListener
+{
+public:
+   ZoomInfo(double start, double pixelsPerSecond);
+   ~ZoomInfo();
+
+   // Be sure we don't slice
+   ZoomInfo(const ZoomInfo&) PROHIBITED;
+   ZoomInfo& operator= (const ZoomInfo&) PROHIBITED;
+
+   void UpdatePrefs() override;
+
+   int vpos;                    // vertical scroll pos
+
+   double h;                    // h pos in secs
+
+protected:
+   double zoom;                 // pixels per second
+
+public:
+   float dBr;                   // decibel scale range
+
+   // do NOT use this once to convert a pixel width to a duration!
+   // Instead, call twice to convert start and end times,
+   // and take the difference.
+   // origin specifies the pixel corresponding to time h
+   double PositionToTime(wxInt64 position,
+      wxInt64 origin = 0
+      , bool ignoreFisheye = false
+   ) const;
+
+   // do NOT use this once to convert a duration to a pixel width!
+   // Instead, call twice to convert start and end positions,
+   // and take the difference.
+   // origin specifies the pixel corresponding to time h
+   wxInt64 TimeToPosition(double time,
+      wxInt64 origin = 0
+      , bool ignoreFisheye = false
+   ) const;
+
+   // This always ignores the fisheye.  Use with caution!
+   // You should prefer to call TimeToPosition twice, for endpoints, and take the difference!
+   double TimeRangeToPixelWidth(double timeRange) const;
+
+   double OffsetTimeByPixels(double time, wxInt64 offset, bool ignoreFisheye = false) const
+   {
+      return PositionToTime(offset + TimeToPosition(time, ignoreFisheye), ignoreFisheye);
+   }
+
+   bool ZoomInAvailable() const;
+   bool ZoomOutAvailable() const;
+
+   static double GetDefaultZoom()
+   { return 44100.0 / 512.0; }
+
+
+   // Limits zoom to certain bounds
+   void SetZoom(double pixelsPerSecond);
+
+   // This function should not be used to convert positions to times and back
+   // Use TimeToPosition and PositionToTime and OffsetTimeByPixels instead
+   double GetZoom() const;
+
+   static double GetMaxZoom( );
+   static double GetMinZoom( );
+
+   // Limits zoom to certain bounds
+   // multipliers above 1.0 zoom in, below out
+   void ZoomBy(double multiplier);
+
+   struct Interval {
+      CONST wxInt64 position; CONST double averageZoom; CONST bool inFisheye;
+      Interval(wxInt64 p, double z, bool i)
+         : position(p), averageZoom(z), inFisheye(i) {}
+   };
+   typedef std::vector<Interval> Intervals;
+
+   // Find an increasing sequence of pixel positions.  Each is the start
+   // of an interval, or is the end position.
+   // Each of the disjoint intervals should be drawn
+   // separately.
+   // It is guaranteed that there is at least one entry and the position of the
+   // first entry equals origin.
+   // @param origin specifies the pixel position corresponding to time ViewInfo::h.
+   void FindIntervals
+      (double rate, Intervals &results, wxInt64 width, wxInt64 origin = 0) const;
+
+   enum FisheyeState {
+      HIDDEN,
+      PINNED,
+
+      NUM_STATES,
+   };
+   FisheyeState GetFisheyeState() const
+   { return HIDDEN; } // stub
+
+   // Return true if the mouse position is anywhere in the fisheye
+   // origin specifies the pixel corresponding to time h
+   bool InFisheye(wxInt64 /*position*/, wxInt64 WXUNUSED(origin = 0)) const
+   {return false;} // stub
+
+   // These accessors ignore the fisheye hiding state.
+   // Inclusive:
+   wxInt64 GetFisheyeLeftBoundary(wxInt64 WXUNUSED(origin = 0)) const
+   {return 0;} // stub
+   // Exclusive:
+   wxInt64 GetFisheyeRightBoundary(wxInt64 WXUNUSED(origin = 0)) const
+   {return 0;} // stub
+};
+
+#endif