several adjustments to node caching system

app/node/block/block.cpp

@@ -127,8 +127,6 @@ void Block::Refresh()
   // Update out point by adding this clip's length to the just calculated in point
   out_point_ = in_point_ + length();
 
-  InvalidateCache(in_point_, out_point_);
-
   emit Refreshed();
 }
 
@@ -176,7 +174,7 @@ void Block::set_media_in(const rational &media_in)
     media_in_ = media_in;
 
     // Signal that this clips contents have changed
-    InvalidateCache(in(), out());
+    InvalidateCache(nullptr, in(), out());
   }
 }
 
@@ -189,3 +187,23 @@ QList<NodeDependency> Block::RunDependencies(NodeOutput* param, const rational &
 
   return QList<NodeDependency>();
 }
+
+rational Block::SequenceToMediaTime(const rational &sequence_time)
+{
+  // These constants are not considered "values" per se, so we don't modify them
+  if (sequence_time == RATIONAL_MIN || sequence_time == RATIONAL_MAX) {
+    return sequence_time;
+  }
+
+  return sequence_time - in() + media_in();
+}
+
+rational Block::MediaToSequenceTime(const rational &media_time)
+{
+  // These constants are not considered "values" per se, so we don't modify them
+  if (media_time == RATIONAL_MIN || media_time == RATIONAL_MAX) {
+    return media_time;
+  }
+
+  return media_time - media_in() + in();
+}

app/node/block/block.h

@@ -104,6 +104,10 @@ signals:
 protected:
   virtual QVariant Value(NodeOutput* output, const rational& time) override;
 
+  rational SequenceToMediaTime(const rational& sequence_time);
+
+  rational MediaToSequenceTime(const rational& media_time);
+
 private:  
   NodeInput* previous_input_;
   NodeOutput* block_output_;

app/node/block/clip/clip.cpp

@@ -67,11 +67,6 @@ NodeInput *ClipBlock::texture_input()
   return texture_input_;
 }
 
-rational ClipBlock::SequenceToMediaTime(const rational &sequence_time)
-{
-  return sequence_time - in() + media_in();
-}
-
 QVariant ClipBlock::Value(NodeOutput* param, const rational& time)
 {
   QVariant value = Block::Value(param, time);
@@ -80,7 +75,7 @@ QVariant ClipBlock::Value(NodeOutput* param, const rational& time)
     // If the time retrieved is within this block, get texture information
     if (time >= in() && time < out()) {
       // We convert the time given (timeline time) to media time
-      rational media_time = SequenceToMediaTime(time - in() + media_in());
+      rational media_time = SequenceToMediaTime(time);
 
       // Retrieve texture
       return texture_input_->get_value(media_time);
@@ -90,3 +85,21 @@ QVariant ClipBlock::Value(NodeOutput* param, const rational& time)
 
   return Block::Value(param, time);
 }
+
+void ClipBlock::InvalidateCache(NodeInput *from, const rational &start_range, const rational &end_range)
+{
+  // If signal is from texture input, transform all times from media time to sequence time
+  if (from == texture_input_) {
+    rational start = MediaToSequenceTime(start_range);
+    rational end = MediaToSequenceTime(end_range);
+
+    // Limit cache invalidation to clip lengths
+    start = qMax(start, in());
+    end = qMin(end, out());
+
+    Node::InvalidateCache(from, start, end);
+  } else {
+    // Otherwise, pass signal along normally
+    Node::InvalidateCache(from, start_range, end_range);
+  }
+}

app/node/block/clip/clip.h

@@ -42,12 +42,12 @@ public:
 
   NodeInput* texture_input();
 
+  virtual void InvalidateCache(NodeInput *from, const rational &start_range, const rational &end_range) override;
+
 protected:
   virtual QVariant Value(NodeOutput* output, const rational& time) override;
 
 private:
-  rational SequenceToMediaTime(const rational& sequence_time);
-
   NodeInput* texture_input_;
 
 };