Merge: Defined EXPERIMENTAL_SCROLLING LIMITS

src/Experimental.h

@@ -181,6 +181,10 @@
 // You must define EXPERIMENTAL_SCRUBBING_BASIC if you enable this:
 #define EXPERIMENTAL_SCRUBBING_SCROLL_WHEEL
 
+// Paul Licameli (PRL) 24 May 2015
+// Allow scrolling up to one half of a screenful beyond either end of the project.
+// This allows smooth-scrolling scrub to work more reasonably at the ends.
+#define EXPERIMENTAL_SCROLLING_LIMITS
 
 // Define to include crash reporting
 #define EXPERIMENTAL_CRASH_REPORT

src/Printing.cpp

@@ -86,7 +86,6 @@ bool AudacityPrintout::OnPrintPage(int WXUNUSED(page))
    viewInfo.h = 0.0;
    viewInfo.screen = mTracks->GetEndTime() - viewInfo.h;
    viewInfo.total = viewInfo.screen;
-   viewInfo.zoom = viewInfo.lastZoom = width / viewInfo.screen;
    int y = rulerPageHeight;
 
    TrackListIterator iter(mTracks);

src/Project.cpp

@@ -174,17 +174,17 @@ ODLock   *AudacityProject::msAllProjectDeleteMutex = new ODLock();
 const int sbarSpaceWidth = 15;
 const int sbarControlWidth = 16;
 const int sbarExtraLen = 1;
-const int sbarHjump = 30;       //STM: This is how far the thumb jumps when the l/r buttons are pressed, or auto-scrolling occurs
+const int sbarHjump = 30;       //STM: This is how far the thumb jumps when the l/r buttons are pressed, or auto-scrolling occurs -- in pixels
 #elif defined(__WXMSW__)
 const int sbarSpaceWidth = 16;
 const int sbarControlWidth = 16;
 const int sbarExtraLen = 0;
-const int sbarHjump = 30;       //STM: This is how far the thumb jumps when the l/r buttons are pressed, or auto-scrolling occurs
+const int sbarHjump = 30;       //STM: This is how far the thumb jumps when the l/r buttons are pressed, or auto-scrolling occurs -- in pixels
 #else // wxGTK, wxMOTIF, wxX11
 const int sbarSpaceWidth = 15;
 const int sbarControlWidth = 15;
 const int sbarExtraLen = 0;
-const int sbarHjump = 30;       //STM: This is how far the thumb jumps when the l/r buttons are pressed, or auto-scrolling occurs
+const int sbarHjump = 30;       //STM: This is how far the thumb jumps when the l/r buttons are pressed, or auto-scrolling occurs -- in pixels
 #include "Theme.h"
 #include "AllThemeResources.h"
 #endif
@@ -811,7 +811,6 @@ AudacityProject::AudacityProject(wxWindow * parent, wxWindowID id,
    mViewInfo.screen = 1.0;
    mViewInfo.h = 0.0;
    mViewInfo.zoom = 44100.0 / 512.0;
-   mViewInfo.lastZoom = mViewInfo.zoom;
 
    // Vertical scrollbar
    mViewInfo.track = NULL;
@@ -1461,7 +1460,13 @@ void AudacityProject::OnScrollRightButton(wxScrollEvent & event)
 //
 void AudacityProject::TP_ScrollWindow(double scrollto)
 {
-   int pos = (int) (scrollto * mViewInfo.zoom * mViewInfo.sbarScale);
+   double timeOffset = 0;
+#ifdef EXPERIMENTAL_SCROLLING_LIMITS
+   timeOffset = mViewInfo.screen / 2.0;
+#endif
+   int pos = (int) (
+      (scrollto + timeOffset) * mViewInfo.zoom * mViewInfo.sbarScale
+   );
    int max = mHsbar->GetRange() - mHsbar->GetThumbSize();
 
    if (pos > max)
@@ -1520,18 +1525,29 @@ void AudacityProject::FixScrollbars()
    int panelWidth, panelHeight;
    mTrackPanel->GetTracksUsableArea(&panelWidth, &panelHeight);
 
-   // Add 1/4 of a screen of blank space to the end of the longest track
    mViewInfo.screen = ((double) panelWidth) / mViewInfo.zoom;
+   double additional, lowerBound;
+#ifdef EXPERIMENTAL_SCROLLING_LIMITS
+   // Add 1/2 of a screen of blank space to the end
+   // and another 1/2 screen before the beginning
+   // so that any point within the union of the selection and the track duration
+   // may be scrolled to the midline.
+   additional = mViewInfo.screen;
+   lowerBound = - additional / 2.0;
+#else
+   // Formerly just added 1/4 screen at the end
+   additional = mViewInfo.screen / 4.0;
+   lowerBound = 0.0;
+#endif
    double LastTime =
-      wxMax( mTracks->GetEndTime(), mViewInfo.selectedRegion.t1() );
-   mViewInfo.total = LastTime + mViewInfo.screen / 4;
+      std::max( mTracks->GetEndTime(), mViewInfo.selectedRegion.t1() );
+   mViewInfo.total = LastTime + additional;
 
    // Don't remove time from total that's still on the screen
-   if (mViewInfo.h > mViewInfo.total - mViewInfo.screen) {
-      mViewInfo.total = mViewInfo.h + mViewInfo.screen;
-   }
-   if (mViewInfo.h < 0.0) {
-      mViewInfo.h = 0.0;
+   mViewInfo.total = std::max(mViewInfo.total, mViewInfo.h + mViewInfo.screen);
+
+   if (mViewInfo.h < lowerBound) {
+      mViewInfo.h = lowerBound;
       rescroll = true;
    }
 
@@ -1603,13 +1619,21 @@ void AudacityProject::FixScrollbars()
    else
       mViewInfo.sbarScale = 1.0; // use maximum resolution
 
+   {
       int scaledSbarH = (int)(mViewInfo.sbarH * mViewInfo.sbarScale);
       int scaledSbarScreen = (int)(mViewInfo.sbarScreen * mViewInfo.sbarScale);
       int scaledSbarTotal = (int)(mViewInfo.sbarTotal * mViewInfo.sbarScale);
+      int offset;
+#ifdef EXPERIMENTAL_SCROLLING_LIMITS
+      offset = scaledSbarScreen / 2;
+#else
+      offset = 0;
+#endif
 
-   mHsbar->SetScrollbar(scaledSbarH, scaledSbarScreen, scaledSbarTotal,
+      mHsbar->SetScrollbar(scaledSbarH + offset, scaledSbarScreen, scaledSbarTotal,
          scaledSbarScreen, TRUE);
       mHsbar->Refresh();
+   }
 
    // Vertical scrollbar
    mVsbar->SetScrollbar(mViewInfo.vpos / mViewInfo.scrollStep,
@@ -1617,7 +1641,6 @@ void AudacityProject::FixScrollbars()
                         totalHeight / mViewInfo.scrollStep,
                         panelHeight / mViewInfo.scrollStep, TRUE);
    mVsbar->Refresh();
-   mViewInfo.lastZoom = mViewInfo.zoom;
 
    if (refresh || (rescroll && mViewInfo.screen < mViewInfo.total)) {
       mTrackPanel->Refresh(false);
@@ -1796,16 +1819,26 @@ void AudacityProject::OnScroll(wxScrollEvent & WXUNUSED(event))
 {
    wxInt64 hlast = mViewInfo.sbarH;
 
-   mViewInfo.sbarH = (wxInt64)
-      (mHsbar->GetThumbPosition() / mViewInfo.sbarScale);
+   double lowerBound;
+   wxInt64 offset;
+#ifdef EXPERIMENTAL_SCROLLING_LIMITS
+   offset = (0.5 + (mViewInfo.zoom * mViewInfo.screen / 2.0));
+   lowerBound = -mViewInfo.screen / 2.0;
+#else
+   offset = 0.0;
+   lowerBound = 0.0;
+#endif
+   mViewInfo.sbarH =
+      (wxInt64)(mHsbar->GetThumbPosition() / mViewInfo.sbarScale) - offset;
 
    if (mViewInfo.sbarH != hlast) {
       mViewInfo.h = mViewInfo.sbarH / mViewInfo.zoom;
 
       if (mViewInfo.h > mViewInfo.total - mViewInfo.screen)
          mViewInfo.h = mViewInfo.total - mViewInfo.screen;
-      if (mViewInfo.h < 0.0)
-         mViewInfo.h = 0.0;
+
+      if (mViewInfo.h < lowerBound)
+         mViewInfo.h = lowerBound;
    }
 
    int lastv = mViewInfo.vpos;

src/TrackPanel.cpp

@@ -1489,7 +1489,11 @@ void TrackPanel::OnPaint(wxPaintEvent & /* event */)
          // the drawing of the tracks.  This prevents flashing of the indicator
          // at higher magnifications, and keeps the green line still in the middle.
          indicator = gAudioIO->GetStreamTime();
-         mViewInfo->h = std::max(0.0, indicator - mViewInfo->screen / 2.0);
+         mViewInfo->h = indicator - mViewInfo->screen / 2.0;
+#if !defined(EXPERIMENTAL_SCROLLING_LIMITS)
+         // Can't scroll too far left
+         mViewInfo->h = std::max(0.0, mViewInfo->h);
+#endif
       }
 #endif
 
@@ -2710,7 +2714,7 @@ void TrackPanel::SelectionHandleClick(wxMouseEvent & event,
       if (startNewSelection) { // mouse is not at an edge, but after
          // quantization, we could be indicating the selection edge
          mSelStartValid = true;
-         mSelStart = PositionToTime(event.m_x, r.x);
+         mSelStart = std::max(0.0, PositionToTime(event.m_x, r.x));
          mStretchStart = nt->NearestBeatTime(mSelStart, &centerBeat);
          if (within(qBeat0, centerBeat, 0.1)) {
             mListener->TP_DisplayStatusMessage(
@@ -2801,8 +2805,10 @@ void TrackPanel::SelectionHandleClick(wxMouseEvent & event,
 void TrackPanel::StartSelection(int mouseXCoordinate, int trackLeftEdge)
 {
    mSelStartValid = true;
-   mSelStart = mViewInfo->h + ((mouseXCoordinate - trackLeftEdge)
-                               / mViewInfo->zoom);
+   mSelStart =
+      std::max(0.0,
+      mViewInfo->h + ((mouseXCoordinate - trackLeftEdge)
+      / mViewInfo->zoom));
 
    double s = mSelStart;
 
@@ -2832,7 +2838,7 @@ void TrackPanel::ExtendSelection(int mouseXCoordinate, int trackLeftEdge,
       // Must be dragging frequency bounds only.
       return;
 
-   double selend = PositionToTime(mouseXCoordinate, trackLeftEdge);
+   double selend = std::max(0.0, PositionToTime(mouseXCoordinate, trackLeftEdge));
    clip_bottom(selend, 0.0);
 
    double origSel0, origSel1;
@@ -3264,7 +3270,7 @@ void TrackPanel::Stretch(int mouseXCoordinate, int trackLeftEdge,
    }
 
    NoteTrack *pNt = (NoteTrack *) pTrack;
-   double moveto = PositionToTime(mouseXCoordinate, trackLeftEdge);
+   double moveto = std::max(0.0, PositionToTime(mouseXCoordinate, trackLeftEdge));
 
    // check to make sure tempo is not higher than 20 beats per second
    // (In principle, tempo can be higher, but not infinity.)

src/ViewInfo.h

@@ -33,7 +33,6 @@ struct ViewInfo {
    double screen;               // screen width in secs
    double total;                // total width in secs
    double zoom;                 // pixels per second
-   double lastZoom;
 
    // Current horizontal scroll bar positions, in pixels
    wxInt64 sbarH;
@@ -43,6 +42,7 @@ struct ViewInfo {
    // Internal wxScrollbar positions are only int in range, so multiply
    // the above values with the following member to get the actual
    // scroll bar positions as reported by the horizontal wxScrollbar's members
+   // i.e. units are scroll increments per pixel
    double sbarScale;
 
    // Vertical scroll step

src/widgets/AttachableScrollBar.cpp

@@ -64,8 +64,6 @@ void AttachableScrollBar::SetScrollBarFromViewInfo()
 
    SetScrollbar(mViewInfo.sbarH, mViewInfo.sbarScreen,
                         mViewInfo.sbarTotal, mViewInfo.sbarScreen, TRUE);
-
-   mViewInfo.lastZoom = mViewInfo.zoom;
 }
 
 // Essentially an int to float conversion.