track: store height in "units" rather than pixels

Fixes DPI scalability issue if a project ever moved from a display with
one DPI to another.

app/node/output/track/track.cpp

@@ -29,6 +29,10 @@
 
 OLIVE_NAMESPACE_ENTER
 
+const double TrackOutput::kTrackHeightDefault = 3.0;
+const double TrackOutput::kTrackHeightMinimum = 1.5;
+const double TrackOutput::kTrackHeightInterval = 0.5;
+
 TrackOutput::TrackOutput() :
   track_type_(Timeline::kTrackTypeNone),
   index_(-1),
@@ -48,7 +52,7 @@ TrackOutput::TrackOutput() :
   AddInput(muted_input_);
 
   // Set default height
-  track_height_ = GetDefaultTrackHeight();
+  track_height_ = kTrackHeightDefault;
 }
 
 void TrackOutput::set_track_type(const Timeline::TrackType &track_type)
@@ -96,21 +100,21 @@ QString TrackOutput::GetTrackName()
   return track_name_;
 }
 
-const int &TrackOutput::GetTrackHeight() const
+const double &TrackOutput::GetTrackHeight() const
 {
   return track_height_;
 }
 
-void TrackOutput::SetTrackHeight(const int &height)
+void TrackOutput::SetTrackHeight(const double &height)
 {
   track_height_ = height;
-  emit TrackHeightChanged(track_height_);
+  emit TrackHeightChangedInPixels(GetTrackHeightInPixels());
 }
 
 void TrackOutput::LoadInternal(QXmlStreamReader *reader, XMLNodeData &xml_node_data)
 {
   if (reader->name() == QStringLiteral("height")) {
-    SetTrackHeight(reader->readElementText().toInt());
+    SetTrackHeight(reader->readElementText().toDouble());
   } else {
     Node::LoadInternal(reader, xml_node_data);
   }
@@ -387,21 +391,6 @@ bool TrackOutput::IsTrack() const
   return true;
 }
 
-int TrackOutput::GetTrackHeightIncrement()
-{
-  return qApp->fontMetrics().height() / 2;
-}
-
-int TrackOutput::GetDefaultTrackHeight()
-{
-  return qApp->fontMetrics().height() * 3;
-}
-
-int TrackOutput::GetTrackHeightMinimum()
-{
-  return qApp->fontMetrics().height() * 3 / 2;
-}
-
 QString TrackOutput::GetDefaultTrackName(Timeline::TrackType type, int index)
 {
   // Starts tracks at 1 rather than 0

app/node/output/track/track.h

@@ -48,8 +48,38 @@ public:
 
   QString GetTrackName();
 
-  const int& GetTrackHeight() const;
-  void SetTrackHeight(const int& height);
+  const double& GetTrackHeight() const;
+  void SetTrackHeight(const double& height);
+
+  int GetTrackHeightInPixels() const
+  {
+    return InternalHeightToPixelHeight(GetTrackHeight());
+  }
+
+  void SetTrackHeightInPixels(int h)
+  {
+    SetTrackHeight(PixelHeightToInternalHeight(h));
+  }
+
+  static int InternalHeightToPixelHeight(double h)
+  {
+    return qRound(h * QFontMetrics(QFont()).height());
+  }
+
+  static double PixelHeightToInternalHeight(int h)
+  {
+    return double(h) / double(QFontMetrics(QFont()).height());
+  }
+
+  static int GetDefaultTrackHeightInPixels()
+  {
+    return InternalHeightToPixelHeight(kTrackHeightDefault);
+  }
+
+  static int GetMinimumTrackHeightInPixels()
+  {
+    return InternalHeightToPixelHeight(kTrackHeightMinimum);
+  }
 
   virtual void Retranslate() override;
 
@@ -172,12 +202,6 @@ public:
 
   virtual bool IsTrack() const override;
 
-  static int GetTrackHeightIncrement();
-
-  static int GetDefaultTrackHeight();
-
-  static int GetTrackHeightMinimum();
-
   static QString GetDefaultTrackName(Timeline::TrackType type, int index);
 
   bool IsMuted() const;
@@ -198,6 +222,10 @@ public:
     return &waveform_lock_;
   }
 
+  static const double kTrackHeightDefault;
+  static const double kTrackHeightMinimum;
+  static const double kTrackHeightInterval;
+
 public slots:
   void SetTrackName(const QString& name);
 
@@ -224,7 +252,7 @@ signals:
   /**
    * @brief Signal emitted when the height of the track has changed
    */
-  void TrackHeightChanged(int height);
+  void TrackHeightChangedInPixels(int pixel_height);
 
   /**
    * @brief Signal emitted when the muted setting changes
@@ -264,7 +292,7 @@ private:
 
   rational track_length_;
 
-  int track_height_;
+  double track_height_;
 
   QString track_name_;
 

app/node/output/track/tracklist.cpp

@@ -190,7 +190,7 @@ void TrackList::TrackConnected(NodeEdgePtr edge)
     connect(connected_track, &TrackOutput::BlockAdded, this, &TrackList::TrackAddedBlock);
     connect(connected_track, &TrackOutput::BlockRemoved, this, &TrackList::TrackRemovedBlock);
     connect(connected_track, &TrackOutput::TrackLengthChanged, this, &TrackList::UpdateTotalLength);
-    connect(connected_track, &TrackOutput::TrackHeightChanged, this, &TrackList::TrackHeightChangedSlot);
+    connect(connected_track, &TrackOutput::TrackHeightChangedInPixels, this, &TrackList::TrackHeightChangedSlot);
 
     connected_track->set_track_type(type_);
 
@@ -233,7 +233,7 @@ void TrackList::TrackDisconnected(NodeEdgePtr edge)
     disconnect(track, &TrackOutput::BlockAdded, this, &TrackList::TrackAddedBlock);
     disconnect(track, &TrackOutput::BlockRemoved, this, &TrackList::TrackRemovedBlock);
     disconnect(track, &TrackOutput::TrackLengthChanged, this, &TrackList::UpdateTotalLength);
-    disconnect(track, &TrackOutput::TrackHeightChanged, this, &TrackList::TrackHeightChangedSlot);
+    disconnect(track, &TrackOutput::TrackHeightChangedInPixels, this, &TrackList::TrackHeightChangedSlot);
 
     emit TrackListChanged();