ViewInfo is becoming a smart class, not a dumb struct

Now it has:
A constructor
XML attribute serializer functions (but no XML tag of its own)

Also removed unused lastZoom

src/LabelDialog.h

@@ -25,7 +25,7 @@ class TrackList;
 class RowData;
 class EmptyLabelRenderer;
 class LabelTrack;
-struct ViewInfo;
+class ViewInfo;
 
 WX_DEFINE_ARRAY(RowData *, RowDataArray);
 

src/Printing.cpp

@@ -15,6 +15,7 @@
 
 
 #include "Audacity.h"
+#include "Printing.h"
 
 #include <wx/defs.h>
 #include <wx/dc.h>
@@ -29,7 +30,6 @@
 #include "ViewInfo.h"
 #include "WaveTrack.h"
 #include "widgets/Ruler.h"
-#include "Printing.h"
 
 // Globals, so that we remember settings from session to session
 static wxPrintData *gPrintData = NULL;
@@ -80,13 +80,8 @@ bool AudacityPrintout::OnPrintPage(int WXUNUSED(page))
    TrackArtist artist;
    artist.SetBackgroundBrushes(*wxWHITE_BRUSH, *wxWHITE_BRUSH,
                                *wxWHITE_PEN, *wxWHITE_PEN);
-   ViewInfo viewInfo;
-   viewInfo.selectedRegion = SelectedRegion();
-   viewInfo.vpos = 0;
-   viewInfo.h = 0.0;
-   viewInfo.screen = mTracks->GetEndTime() - viewInfo.h;
-   viewInfo.total = viewInfo.screen;
-   viewInfo.zoom = width / viewInfo.screen;
+   const double screenDuration = mTracks->GetEndTime();
+   ViewInfo viewInfo(0.0, screenDuration, width / screenDuration);
    int y = rulerPageHeight;
 
    TrackListIterator iter(mTracks);

src/Project.cpp

@@ -780,6 +780,7 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
      mTimerRecordCanceled(false),
      mMenuClose(false)
      , mbInitializingScrollbar(false)
+     , mViewInfo(0.0, 1.0, (44100.0 / 512.0))
 {
    // Note that the first field of the status bar is a dummy, and it's width is set
    // to zero latter in the code. This field is needed for wxWidgets 2.8.12 because
@@ -810,26 +811,6 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
    // Initialize view info (shared with TrackPanel)
    //
 
-   // Selection
-   mViewInfo.selectedRegion = SelectedRegion();
-
-   // Horizontal scrollbar
-   mViewInfo.total = 1.0;
-   mViewInfo.screen = 1.0;
-   mViewInfo.h = 0.0;
-   mViewInfo.zoom = 44100.0 / 512.0;
-
-   // Vertical scrollbar
-   mViewInfo.track = NULL;
-   mViewInfo.vpos = 0;
-
-   mViewInfo.scrollStep = 16;
-
-   mViewInfo.sbarH = 0;
-   mViewInfo.sbarScreen = 1;
-   mViewInfo.sbarTotal = 1;
-   mViewInfo.sbarScale = 1.0;
-
    UpdatePrefs();
 
    mLockPlayRegion = false;
@@ -2902,6 +2883,12 @@ bool AudacityProject::HandleXMLTag(const wxChar *tag, const wxChar **attrs)
       if (!value || !XMLValueChecker::IsGoodString(value))
          break;
 
+      if (mViewInfo.ReadXMLAttribute(attr, value)) {
+         // We need to save vpos now and restore it below
+         longVpos = std::max(longVpos, long(mViewInfo.vpos));
+         continue;
+      }
+
       if (!wxStrcmp(attr, wxT("datadir")))
       {
          //
@@ -2995,20 +2982,6 @@ bool AudacityProject::HandleXMLTag(const wxChar *tag, const wxChar **attrs)
          requiredTags++;
       }
 
-      else if (mViewInfo.selectedRegion
-         .HandleXMLAttribute(attr, value, wxT("sel0"), wxT("sel1"))) {
-      }
-
-      else if (!wxStrcmp(attr, wxT("vpos")))
-         // Just assign a variable, put the value in its place later 
-         wxString(value).ToLong(&longVpos);
-
-      else if (!wxStrcmp(attr, wxT("h")))
-         Internat::CompatibleToDouble(value, &mViewInfo.h);
-
-      else if (!wxStrcmp(attr, wxT("zoom")))
-         Internat::CompatibleToDouble(value, &mViewInfo.zoom);
-
       else if (!wxStrcmp(attr, wxT("rate"))) {
          Internat::CompatibleToDouble(value, &mRate);
          GetSelectionBar()->SetRate(mRate);
@@ -3202,12 +3175,8 @@ void AudacityProject::WriteXML(XMLWriter &xmlFile)
    xmlFile.WriteAttr(wxT("projname"), projName);
    xmlFile.WriteAttr(wxT("version"), wxT(AUDACITY_FILE_FORMAT_VERSION));
    xmlFile.WriteAttr(wxT("audacityversion"), AUDACITY_VERSION_STRING);
-   mViewInfo.selectedRegion
-      .WriteXMLAttributes(xmlFile, wxT("sel0"), wxT("sel1"));
-   // PRL: to do: persistence of other fields of the selection
-   xmlFile.WriteAttr(wxT("vpos"), mViewInfo.vpos);
-   xmlFile.WriteAttr(wxT("h"), mViewInfo.h, 10);
-   xmlFile.WriteAttr(wxT("zoom"), mViewInfo.zoom, 10);
+
+   mViewInfo.WriteXMLAttributes(xmlFile);
    xmlFile.WriteAttr(wxT("rate"), mRate);
    xmlFile.WriteAttr(wxT("snapto"), GetSnapTo() ? wxT("on") : wxT("off"));
    xmlFile.WriteAttr(wxT("selectionformat"), GetSelectionFormat());

src/ShuttleGui.h

@@ -325,7 +325,7 @@ class GuiWaveTrack;
 class AdornedRulerPanel;
 class RulerPanel;
 class AttachableScrollBar;
-struct ViewInfo;
+class ViewInfo;
 #include <wx/scrolbar.h>  // to get wxSB_HORIZONTAL
 
 // CreateStdButtonSizer defs...should probably move to widgets subdir

src/TrackArtist.h

@@ -37,7 +37,7 @@ class LabelTrack;
 class TimeTrack;
 class TrackList;
 class Ruler;
-struct ViewInfo;
+class ViewInfo;
 
 #ifndef uchar
 typedef unsigned char uchar;

src/TrackPanel.h

@@ -45,7 +45,7 @@ class AudacityProject;
 
 class TrackPanelAx;
 
-struct ViewInfo;
+class ViewInfo;
 
 WX_DEFINE_ARRAY(LWSlider *, LWSliderArray);
 

src/ViewInfo.cpp

@@ -0,0 +1,66 @@
+/**********************************************************************
+
+Audacity: A Digital Audio Editor
+
+ViewInfo.cpp
+
+Paul Licameli
+
+**********************************************************************/
+
+#include "ViewInfo.h"
+
+#include "Internat.h"
+#include "xml/XMLWriter.h"
+
+ViewInfo::ViewInfo(double start, double screenDuration, double pixelsPerSecond)
+   : selectedRegion()
+   , track(0)
+   , vpos(0)
+   , h(start)
+   , screen(screenDuration)
+   , total(screen)
+   , zoom(pixelsPerSecond)
+
+   , sbarH(0)
+   , sbarScreen(1)
+   , sbarTotal(1)
+   , sbarScale(1.0)
+   , scrollStep(16)
+
+   , bUpdateTrackIndicator(true)
+{
+}
+
+void ViewInfo::WriteXMLAttributes(XMLWriter &xmlFile)
+{
+   selectedRegion.WriteXMLAttributes(xmlFile, wxT("sel0"), wxT("sel1"));
+   xmlFile.WriteAttr(wxT("vpos"), vpos);
+   xmlFile.WriteAttr(wxT("h"), h, 10);
+   xmlFile.WriteAttr(wxT("zoom"), zoom, 10);
+}
+
+bool ViewInfo::ReadXMLAttribute(const wxChar *attr, const wxChar *value)
+{
+   if (selectedRegion.HandleXMLAttribute(attr, value, wxT("sel0"), wxT("sel1")))
+      return true;
+
+   if (!wxStrcmp(attr, wxT("vpos"))) {
+      long longVpos;
+      wxString(value).ToLong(&longVpos);
+      vpos = int(longVpos);
+      return true;
+   }
+
+   if (!wxStrcmp(attr, wxT("h"))) {
+      Internat::CompatibleToDouble(value, &h);
+      return true;
+   }
+
+   if (!wxStrcmp(attr, wxT("zoom"))) {
+      Internat::CompatibleToDouble(value, &zoom);
+      return true;
+   }
+
+   return false;
+}

src/ViewInfo.h

@@ -18,7 +18,11 @@ const double gMaxZoom = 6000000,
 
 class Track;
 
-struct ViewInfo {
+class AUDACITY_DLL_API ViewInfo
+{
+public:
+
+   ViewInfo(double start, double screenDuration, double pixelsPerSecond);
 
    // Current selection
 
@@ -52,6 +56,9 @@ struct ViewInfo {
    // drawing the waveform. Maybe this should be put somewhere else?
 
    bool bUpdateTrackIndicator;
+
+   void WriteXMLAttributes(XMLWriter &xmlFile);
+   bool ReadXMLAttribute(const wxChar *attr, const wxChar *value);
 };
 
 #endif

src/widgets/AttachableScrollBar.h

@@ -19,7 +19,7 @@
 
 #include <wx/scrolbar.h>
 
-struct ViewInfo;
+class ViewInfo;
 
 class AUDACITY_DLL_API AttachableScrollBar :
    public wxScrollBar

src/widgets/Ruler.h

@@ -19,7 +19,7 @@
 #include "../Envelope.h"
 #include "../Experimental.h"
 
-struct ViewInfo;
+class ViewInfo;
 class AudacityProject;
 class TimeTrack;
 class SnapManager;