Fix bug 1575

Includes fix by PRL:
https://github.com/Paul-Licameli/audacity/commit/cbca44e

src/Menus.cpp

@@ -1695,7 +1695,7 @@ CommandFlag AudacityProject::GetFocusedFrame()
    return AlwaysEnabledFlag;
 }
 
-CommandFlag AudacityProject::GetUpdateFlags()
+CommandFlag AudacityProject::GetUpdateFlags(bool checkActive)
 {
    // This method determines all of the flags that determine whether
    // certain menu items and commands should be enabled or disabled,
@@ -1703,6 +1703,16 @@ CommandFlag AudacityProject::GetUpdateFlags()
    // have changed, it's not necessary to even check for updates.
    auto flags = AlwaysEnabledFlag;
 
+   if (auto focus = wxWindow::FindFocus()) {
+      while (focus && focus->GetParent())
+         focus = focus->GetParent();
+      if (focus && !static_cast<wxTopLevelWindow*>(focus)->IsIconized())
+         flags |= NotMinimizedFlag;
+   }
+
+   if ( checkActive && !IsActive() )
+      return flags;
+
    if (!gAudioIO->IsAudioTokenActive(GetAudioIOToken()))
       flags |= AudioIONotBusyFlag;
    else
@@ -1791,8 +1801,11 @@ CommandFlag AudacityProject::GetUpdateFlags()
    if (ZoomOutAvailable() && (flags & TracksExistFlag))
       flags |= ZoomOutAvailableFlag;
 
-   if ((flags & LabelTracksExistFlag) && LabelTrack::IsTextClipSupported())
-      flags |= TextClipFlag;
+   // TextClipFlag is currently unused (Jan 2017, 2.1.3 alpha)
+   // and LabelTrack::IsTextClipSupported() is quite slow on Linux,
+   // so disable for now (See bug 1575).
+   // if ((flags & LabelTracksExistFlag) && LabelTrack::IsTextClipSupported())
+   //    flags |= TextClipFlag;
 
    flags |= GetFocusedFrame();
 
@@ -1829,13 +1842,6 @@ CommandFlag AudacityProject::GetUpdateFlags()
    if (bar->ControlToolBar::CanStopAudioStream())
       flags |= CanStopAudioStreamFlag;
 
-   if (auto focus = wxWindow::FindFocus()) {
-      while (focus && focus->GetParent())
-         focus = focus->GetParent();
-      if (focus && !static_cast<wxTopLevelWindow*>(focus)->IsIconized())
-         flags |= NotMinimizedFlag;
-   }
-
    return flags;
 }
 
@@ -1928,7 +1934,7 @@ void AudacityProject::ModifyToolbarMenus()
 
 // checkActive is a temporary hack that should be removed as soon as we
 // get multiple effect preview working
-void AudacityProject::UpdateMenus(bool /*checkActive*/)
+void AudacityProject::UpdateMenus(bool checkActive)
 {
    //ANSWER-ME: Why UpdateMenus only does active project?
    //JKC: Is this test fixing a bug when multiple projects are open?
@@ -1936,10 +1942,7 @@ void AudacityProject::UpdateMenus(bool /*checkActive*/)
    if (this != GetActiveProject())
       return;
 
-   //if (checkActive && !IsActive())
-     // return;
-
-   auto flags = GetUpdateFlags();
+   auto flags = GetUpdateFlags(checkActive);
    auto flags2 = flags;
 
    // We can enable some extra items if we have select-all-on-none.

src/Menus.h

@@ -38,7 +38,10 @@ void ModifyToolbarMenus();
 void ModifyAllProjectToolbarMenus();
 
 CommandFlag GetFocusedFrame();
-CommandFlag GetUpdateFlags();
+
+// If checkActive, do not do complete flags testing on an
+// inactive project as it is needlessly expensive.
+CommandFlag GetUpdateFlags(bool checkActive = false);
 
 double NearestZeroCrossing(double t0);
 

src/widgets/ProgressDialog.cpp

@@ -1234,6 +1234,7 @@ bool ProgressDialog::Create(const wxString & title,
 
    mStartTime = wxGetLocalTimeMillis().GetValue();
    mLastUpdate = mStartTime;
+   mYieldTimer = mStartTime;
    mCancel = false;
    mStop = false;
 
@@ -1346,7 +1347,13 @@ int ProgressDialog::Update(int value, const wxString & message)
    //      (and probably other things).  I do not yet know why this happens and
    //      I'm not too keen on having timer events processed here, but you do
    //      what you have to do.
-   wxEventLoopBase::GetActive()->YieldFor(wxEVT_CATEGORY_UI | wxEVT_CATEGORY_USER_INPUT | wxEVT_CATEGORY_TIMER);
+
+   // Nyquist effects call Update on every callback, but YieldFor is
+   // quite slow on Linux / Mac, so don't call too frequently. (bug 1575)
+   if ((now - mYieldTimer > 50) || (value == 1000)) {
+      wxEventLoopBase::GetActive()->YieldFor(wxEVT_CATEGORY_UI | wxEVT_CATEGORY_USER_INPUT | wxEVT_CATEGORY_TIMER);
+      mYieldTimer = now;
+   }
 
    return eProgressSuccess;
 }

src/widgets/ProgressDialog.h

@@ -90,6 +90,7 @@ protected:
 
    wxLongLong_t mStartTime;
    wxLongLong_t mLastUpdate;
+   wxLongLong_t mYieldTimer;
    int mLastValue; // gauge value, range = [0,1000]
 
    bool mCancel;