From ec723466ba5129a336503f5100ecf900491c2d4a Mon Sep 17 00:00:00 2001
From: Paul Licameli <paul.licameli@audacityteam.org>
Date: Wed, 22 Jan 2020 13:30:25 -0500
Subject: [PATCH] Invalidate Ruler, whenever anything the Updater uses is
 reassigned

---
 src/widgets/Ruler.cpp | 31 +++++++++++++++++++++++--------
 src/widgets/Ruler.h   |  2 +-
 2 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/src/widgets/Ruler.cpp b/src/widgets/Ruler.cpp
index db9146184..0b751280b 100644
--- a/src/widgets/Ruler.cpp
+++ b/src/widgets/Ruler.cpp
@@ -172,6 +172,15 @@ void Ruler::SetUnits(const TranslatableString &units)
    }
 }
 
+void Ruler::SetDbMirrorValue( const double d )
+{
+   if (mDbMirrorValue != d) {
+      mDbMirrorValue = d;
+
+      Invalidate();
+   }
+}
+
 void Ruler::SetOrientation(int orient)
 {
    // wxHORIZONTAL || wxVERTICAL
@@ -303,14 +312,18 @@ void Ruler::SetNumberScale(const NumberScale *pScale)
 
 void Ruler::OfflimitsPixels(int start, int end)
 {
-   if ( mUserBits.empty() ) {
-      if (mOrientation == wxHORIZONTAL)
-         mLength = mRight-mLeft;
-      else
-         mLength = mBottom-mTop;
-      if( mLength < 0 )
-         return;
-      mUserBits.resize( static_cast<size_t>( mLength + 1 ), false );
+   int length = mLength;
+   if (mOrientation == wxHORIZONTAL)
+      length = mRight - mLeft;
+   else
+      length = mBottom - mTop;
+   if( length < 0 )
+      return;
+
+   auto size = static_cast<size_t>( length + 1 );
+   if ( mUserBits.size() < size ) {
+      mLength = length;
+      mUserBits.resize( size, false );
    }
 
    if (end < start)
@@ -323,6 +336,8 @@ void Ruler::OfflimitsPixels(int start, int end)
 
    for(int i = start; i <= end; i++)
       mUserBits[i] = true;
+
+   Invalidate();
 }
 
 void Ruler::SetBounds(int left, int top, int right, int bottom)
diff --git a/src/widgets/Ruler.h b/src/widgets/Ruler.h
index 3a0d17fb0..356465856 100644
--- a/src/widgets/Ruler.h
+++ b/src/widgets/Ruler.h
@@ -76,7 +76,7 @@ class AUDACITY_DLL_API Ruler {
    // Specify the name of the units (like "dB") if you
    // want numbers like "1.6" formatted as "1.6 dB".
    void SetUnits(const TranslatableString &units);
-   void SetDbMirrorValue( const double d ){ mDbMirrorValue = d ; };
+   void SetDbMirrorValue( const double d );
 
    // Logarithmic
    void SetLog(bool log);