Reviewed use of Track::GetY; don't use in NoteTrack; fix off-by-1's

src/NoteTrack.cpp

@@ -907,26 +907,26 @@ void NoteTrack::VScroll(int start, int end)
 
 // Zoom the note track, centering the pitch at centerY,
 // amount is 1 for zoom in, and -1 for zoom out
-void NoteTrack::Zoom(int centerY, int amount)
+void NoteTrack::Zoom(const wxRect &rect, int centerY, int amount)
 {
    // Construct track rectangle to map pitch to screen coordinates
    // Only y and height are needed:
-   wxRect trackRect(0, GetY(), 1, GetHeight());
+   wxRect trackRect(0, rect.GetY(), 1, rect.GetHeight());
    PrepareIPitchToY(trackRect);
    int centerPitch = YToIPitch(centerY);
    // zoom out by changing the pitch height -- a small integer
    mPitchHeight += amount;
    if (mPitchHeight <= 0) mPitchHeight = 1;
    PrepareIPitchToY(trackRect); // update because mPitchHeight changed
-   int newCenterPitch = YToIPitch(GetY() + GetHeight() / 2);
+   int newCenterPitch = YToIPitch(rect.GetY() + rect.GetHeight() / 2);
    // center the pitch that the user clicked on
    SetBottomNote(mBottomNote + (centerPitch - newCenterPitch));
 }
 
 
-void NoteTrack::ZoomTo(int start, int end)
+void NoteTrack::ZoomTo(const wxRect &rect, int start, int end)
 {
-   wxRect trackRect(0, GetY(), 1, GetHeight());
+   wxRect trackRect(0, rect.GetY(), 1, rect.GetHeight());
    PrepareIPitchToY(trackRect);
    int topPitch = YToIPitch(start);
    int botPitch = YToIPitch(end);
@@ -934,7 +934,7 @@ void NoteTrack::ZoomTo(int start, int end)
       int temp = topPitch; topPitch = botPitch; botPitch = temp;
    }
    if (topPitch == botPitch) { // can't divide by zero, do something else
-      Zoom(start, 1);
+      Zoom(rect, start, 1);
       return;
    }
    int trialPitchHeight = trackRect.height / (topPitch - botPitch);
@@ -943,7 +943,7 @@ void NoteTrack::ZoomTo(int start, int end)
    } else if (trialPitchHeight == 0) {
       trialPitchHeight = 1;
    }
-   Zoom((start + end) / 2, trialPitchHeight - mPitchHeight);
+   Zoom(rect, (start + end) / 2, trialPitchHeight - mPitchHeight);
 }
 
 int NoteTrack::YToIPitch(int y)

src/NoteTrack.h

@@ -121,10 +121,10 @@ class AUDACITY_DLL_API NoteTrack final
    int GetBottomNote() const { return mBottomNote; }
    int GetPitchHeight() const { return mPitchHeight; }
    void SetPitchHeight(int h) { mPitchHeight = h; }
-   void ZoomOut(int y) { Zoom(y, -1); }
+   void ZoomOut(const wxRect &rect, int y) { Zoom(rect, y, -1); }
-   void ZoomIn(int y) { Zoom(y, 1); }
+   void ZoomIn(const wxRect &rect, int y) { Zoom(rect, y, 1); }
-   void Zoom(int centerY, int amount);
+   void Zoom(const wxRect &rect, int centerY, int amount);
-   void ZoomTo(int start, int end);
+   void ZoomTo(const wxRect &rect, int start, int end);
    int GetNoteMargin() const { return (mPitchHeight + 1) / 2; }
    int GetOctaveHeight() const { return mPitchHeight * 12 + 2; }
    // call this once before a series of calls to IPitchToY(). It

src/Project.cpp

@@ -2009,7 +2009,8 @@ Track *AudacityProject::GetFirstVisible()
       for (Track *t = iter.First(); t; t = iter.Next()) {
          int y = t->GetY();
          int h = t->GetHeight();
-         if (y >= mViewInfo.vpos || y + h >= mViewInfo.vpos) {
+         if (y + h - 1 >= mViewInfo.vpos) {
+            // At least the bottom row of pixels is not scrolled away above
             mViewInfo.track = t;
             break;
          }
@@ -2028,8 +2029,8 @@ void AudacityProject::UpdateFirstVisible()
    Track *t = mViewInfo.track;
    mViewInfo.track = NULL;
 
-   if (t->GetY() > mViewInfo.vpos) {
+   if (t->GetY() >= mViewInfo.vpos) {
-      while (t && t->GetY() > mViewInfo.vpos) {
+      while (t && t->GetY() >= mViewInfo.vpos) {
          t = mTracks->GetPrev(t);
       }
    }
@@ -2037,7 +2038,8 @@ void AudacityProject::UpdateFirstVisible()
    while (t) {
       int y = t->GetY();
       int h = t->GetHeight();
-      if (y >= mViewInfo.vpos || y + h >= mViewInfo.vpos) {
+      if (y + h - 1 >= mViewInfo.vpos) {
+         // At least the bottom row of pixels is not scrolled away above
          mViewInfo.track = t;
          return;
       }

src/TrackPanel.cpp

@@ -4289,12 +4289,18 @@ void TrackPanel::HandleVZoomButtonUp( wxMouseEvent & event )
    // which we then return
    if (mCapturedTrack->GetKind() == Track::Note) {
       NoteTrack *nt = (NoteTrack *) mCapturedTrack;
+      const wxRect rect{
+         GetLeftOffset(),
+         mCapturedTrack->GetY() + kTopMargin,
+         GetSize().GetWidth() - GetLeftOffset(),
+         mCapturedTrack->GetHeight() - (kTopMargin + kBottomMargin)
+      };
       if (IsDragZooming()) {
-         nt->ZoomTo(mZoomStart, mZoomEnd);
+         nt->ZoomTo(rect, mZoomStart, mZoomEnd);
       } else if (event.ShiftDown() || event.RightUp()) {
-         nt->ZoomOut(mZoomEnd);
+         nt->ZoomOut(rect, mZoomEnd);
       } else {
-         nt->ZoomIn(mZoomEnd);
+         nt->ZoomIn(rect, mZoomEnd);
       }
       mZoomEnd = mZoomStart = 0;
       Refresh(false);
@@ -9611,6 +9617,7 @@ void TrackInfo::DrawVelocitySlider(wxDC *dc, NoteTrack *t, wxRect rect, bool cap
 
 LWSlider * TrackInfo::GainSlider(WaveTrack *t, bool captured) const
 {
+   // PRL:  Add the inset, but why not also the border?
    wxRect rect(kLeftInset, t->GetY() - pParent->GetViewInfo()->vpos + kTopInset, 1, t->GetHeight());
    wxRect sliderRect;
    GetGainRect(rect, sliderRect);
@@ -9628,6 +9635,7 @@ LWSlider * TrackInfo::GainSlider(WaveTrack *t, bool captured) const
 
 LWSlider * TrackInfo::PanSlider(WaveTrack *t, bool captured) const
 {
+   // PRL:  Add the inset, but why not also the border?
    wxRect rect(kLeftInset, t->GetY() - pParent->GetViewInfo()->vpos + kTopInset, 1, t->GetHeight());
    wxRect sliderRect;
    GetPanRect(rect, sliderRect);
@@ -9646,6 +9654,7 @@ LWSlider * TrackInfo::PanSlider(WaveTrack *t, bool captured) const
 #ifdef EXPERIMENTAL_MIDI_OUT
 LWSlider * TrackInfo::VelocitySlider(NoteTrack *t, bool captured) const
 {
+   // PRL:  Add the inset, but why not also the border?
    wxRect rect(kLeftInset, t->GetY() - pParent->GetViewInfo()->vpos + kTopInset, 1, t->GetHeight());
    wxRect sliderRect;
    GetVelocityRect(rect, sliderRect);

src/tracks/ui/EditCursorOverlay.cpp

@@ -122,10 +122,11 @@ void EditCursorOverlay::Draw(OverlayPanel &panel, wxDC &dc)
 
 #ifdef EXPERIMENTAL_OUTPUT_DISPLAY
             if (MONO_WAVE_PAN(pTrack)){
-               auto y = pTrack->GetY(true) - viewInfo.vpos + 1;
+               auto y = pTrack->GetY(true) - viewInfo.vpos;
-               auto top = y + kTopInset;
+               auto top = y + kTopMargin;
-               auto bottom = y + pTrack->GetHeight(true) - kTopInset;
+               auto height = pTrack->GetHeight(true) - (kTopMargin + kBottomMargin);
-               AColor::Line(dc, mLastCursorX, top, mLastCursorX, bottom);
+               // - 1 because AColor::Line is inclusive of endpoint
+               AColor::Line(dc, mLastCursorX, top, mLastCursorX, top + height - 1);
             }
 #endif