track: provide control over invalidation when setting length

app/node/output/track/track.cpp

@@ -239,7 +239,7 @@ const QList<Block *> &TrackOutput::Blocks() const
 void TrackOutput::InvalidateCache(const TimeRange &range, NodeInput *from, NodeInput *source)
 {
   if (block_invalidate_cache_stack_ == 0) {
-    PushLengthChangeSignal();
+    PushLengthChangeSignal(true);
 
     Node::InvalidateCache(TimeRange(qMax(range.in(), rational(0)), qMin(range.out(), track_length())), from, source);
   }
@@ -429,11 +429,11 @@ void TrackOutput::Hash(QCryptographicHash &hash, const rational &time) const
   }
 }
 
-void TrackOutput::PushLengthChangeSignal()
+void TrackOutput::PushLengthChangeSignal(bool invalidate)
 {
   if (queued_length_change_) {
     queued_length_change_ = false;
-    SetLengthInternal(queued_length_);
+    SetLengthInternal(queued_length_, invalidate);
   }
 }
 
@@ -491,7 +491,7 @@ int TrackOutput::GetInputIndexFromCacheIndex(Block *block)
   return -1;
 }
 
-void TrackOutput::SetLengthInternal(const rational &r)
+void TrackOutput::SetLengthInternal(const rational &r, bool invalidate)
 {
   if (block_invalidate_cache_stack_ > 0) {
     queued_length_change_ = true;
@@ -508,9 +508,11 @@ void TrackOutput::SetLengthInternal(const rational &r)
     track_length_ = r;
     emit TrackLengthChanged();
 
-    InvalidateCache(invalidate_range,
-                    block_input_,
-                    block_input_);
+    if (invalidate) {
+      InvalidateCache(invalidate_range,
+                      block_input_,
+                      block_input_);
+    }
   }
 }
 

app/node/output/track/track.h

@@ -192,7 +192,7 @@ public:
 
   virtual void Hash(QCryptographicHash& hash, const rational &time) const override;
 
-  void PushLengthChangeSignal();
+  void PushLengthChangeSignal(bool invalidate = false);
 
   AudioVisualWaveform& waveform()
   {
@@ -255,7 +255,7 @@ private:
   int GetInputIndexFromCacheIndex(int cache_index);
   int GetInputIndexFromCacheIndex(Block* block);
 
-  void SetLengthInternal(const rational& r);
+  void SetLengthInternal(const rational& r, bool invalidate = true);
 
   QList<Block*> block_cache_;