Drawing sequence for overlays independent of insertion call sequence

src/AdornedRulerPanel.cpp

@@ -130,6 +130,8 @@ public:
 private:
    AdornedRulerPanel *GetRuler() const;
 
+   unsigned SequenceNumber() const override;
+
    std::pair<wxRect, bool> DoGetRectangle(wxSize size) override;
    void Draw(OverlayPanel &panel, wxDC &dc) override;
 
@@ -159,6 +161,7 @@ public:
    QuickPlayIndicatorOverlay(AudacityProject *project);
 
 private:
+   unsigned SequenceNumber() const override;
    std::pair<wxRect, bool> DoGetRectangle(wxSize size) override;
    void Draw(OverlayPanel &panel, wxDC &dc) override;
 
@@ -229,6 +232,12 @@ void AdornedRulerPanel::QuickPlayRulerOverlay::Update()
    }
 }
 
+unsigned
+AdornedRulerPanel::QuickPlayRulerOverlay::SequenceNumber() const
+{
+   return 30;
+}
+
 std::pair<wxRect, bool>
 AdornedRulerPanel::QuickPlayRulerOverlay::DoGetRectangle(wxSize /*size*/)
 {
@@ -284,6 +293,12 @@ AdornedRulerPanel::QuickPlayIndicatorOverlay::QuickPlayIndicatorOverlay(
 {
 }
 
+unsigned
+AdornedRulerPanel::QuickPlayIndicatorOverlay::SequenceNumber() const
+{
+   return 30;
+}
+
 std::pair<wxRect, bool>
 AdornedRulerPanel::QuickPlayIndicatorOverlay::DoGetRectangle(wxSize size)
 {

src/Project.cpp

@@ -1310,7 +1310,7 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
       &ViewInfo::OnTimer,
       &mViewInfo);
 
-   // Add the overlays, in the sequence in which they will be painted
+   // Add the overlays
    mTrackPanel->AddOverlay( mIndicatorOverlay );
    mTrackPanel->AddOverlay( mCursorOverlay );
 #ifdef EXPERIMENTAL_SCRUBBING_BASIC

src/tracks/ui/EditCursorOverlay.cpp

@@ -36,6 +36,11 @@ EditCursorOverlay::EditCursorOverlay(AudacityProject *project, bool isMaster)
 {
 }
 
+unsigned EditCursorOverlay::SequenceNumber() const
+{
+   return 20;
+}
+
 std::pair<wxRect, bool> EditCursorOverlay::DoGetRectangle(wxSize size)
 {
    const auto &selection = mProject->GetViewInfo().selectedRegion;

src/tracks/ui/EditCursorOverlay.h

@@ -22,6 +22,7 @@ public:
    EditCursorOverlay(AudacityProject *project, bool isMaster = true);
 
 private:
+   unsigned SequenceNumber() const override;
    std::pair<wxRect, bool> DoGetRectangle(wxSize size) override;
    void Draw(OverlayPanel &panel, wxDC &dc) override;
 

src/tracks/ui/PlayIndicatorOverlay.cpp

@@ -42,6 +42,11 @@ PlayIndicatorOverlayBase::~PlayIndicatorOverlayBase()
 {
 }
 
+unsigned PlayIndicatorOverlayBase::SequenceNumber() const
+{
+   return 10;
+}
+
 std::pair<wxRect, bool> PlayIndicatorOverlayBase::DoGetRectangle(wxSize size)
 {
    auto width = mIsMaster ? 1 : IndicatorMediumWidth;

src/tracks/ui/PlayIndicatorOverlay.h

@@ -28,6 +28,7 @@ public:
    void Update(int newIndicatorX) { mNewIndicatorX = newIndicatorX; }
 
 private:
+   unsigned SequenceNumber() const override;
    std::pair<wxRect, bool> DoGetRectangle(wxSize size) override;
    void Draw(OverlayPanel &panel, wxDC &dc) override;
 

src/tracks/ui/Scrubbing.cpp

@@ -886,6 +886,11 @@ ScrubbingOverlay::ScrubbingOverlay(AudacityProject *project)
       this);
 }
 
+unsigned ScrubbingOverlay::SequenceNumber() const
+{
+   return 40;
+}
+
 std::pair<wxRect, bool> ScrubbingOverlay::DoGetRectangle(wxSize)
 {
    wxRect rect(mLastScrubRect);

src/tracks/ui/Scrubbing.h

@@ -216,6 +216,7 @@ public:
    ScrubbingOverlay(AudacityProject *project);
 
 private:
+   unsigned SequenceNumber() const override;
    std::pair<wxRect, bool> DoGetRectangle(wxSize size) override;
    void Draw(OverlayPanel &panel, wxDC &dc) override;
 

src/widgets/Overlay.h

@@ -93,6 +93,10 @@ class Overlay
 public:
    virtual ~Overlay() = 0;
 
+   ///\brief This number determines an ordering of overlays, so that those
+   /// with higher numbers overpaint those with lower numbers that intersect
+   virtual unsigned SequenceNumber() const = 0;
+
    // nonvirtual wrapper
    std::pair<wxRect, bool> GetRectangle(wxSize size);
 

src/widgets/OverlayPanel.cpp

@@ -23,7 +23,16 @@ OverlayPanel::OverlayPanel(wxWindow * parent, wxWindowID id,
 
 void OverlayPanel::AddOverlay( const std::weak_ptr<Overlay> &pOverlay)
 {
-   mOverlays.push_back(pOverlay);
+   if (pOverlay.expired())
+      return;
+   Compress();
+   auto iter = std::lower_bound( mOverlays.begin(), mOverlays.end(),
+      pOverlay.lock()->SequenceNumber(),
+      []( const OverlayPtr &p, unsigned value ) {
+         return p.expired() || p.lock()->SequenceNumber() < value;
+      }
+   );
+   mOverlays.insert(iter, pOverlay);
 }
 
 void OverlayPanel::ClearOverlays()

src/widgets/OverlayPanel.h

@@ -40,8 +40,10 @@ public:
    void DrawOverlays(bool repaint_all, wxDC *pDC = nullptr);
    
 private:
+   using OverlayPtr = std::weak_ptr<Overlay>;
+
    void Compress();
-   std::vector< std::weak_ptr<Overlay> > mOverlays;
+   std::vector< OverlayPtr > mOverlays;
    
    
    DECLARE_EVENT_TABLE()