MLTTrack: Reimplement the move function to specify position in frames

src/Backend/ITrack.h

@@ -37,7 +37,7 @@ namespace Backend
         virtual void        replaceWithBlank( int index ) = 0;
         virtual bool        append( IInput& input ) = 0;
         virtual bool        remove( int index ) = 0;
-        // src and dist are indexes.
+        // src and dist are frames.
         virtual bool        move( int src, int dist ) = 0;
         virtual IInput*     clip( int index ) const = 0;
         virtual IInput*     clipAt( int64_t position ) const = 0 ;

src/Backend/MLT/MLTTrack.cpp

@@ -114,7 +114,12 @@ MLTTrack::remove( int index )
 bool
 MLTTrack::move( int src, int dist )
 {
-    return !playlist()->move( src, dist );
+    std::unique_ptr<Mlt::Producer> prod(
+                playlist()->replace_with_blank( playlist()->get_clip_index_at( src ) ) );
+    if ( !prod )
+        return false;
+    playlist()->consolidate_blanks( 0 );
+    return !playlist()->insert_at( dist, prod.get(), 1 );
 }
 
 Backend::IInput*

src/Workflow/TrackWorkflow.cpp

@@ -130,11 +130,7 @@ TrackWorkflow::moveClip( const QUuid& id, qint64 startingFrame )
         {
             auto clip = it.value();
             auto track = trackFromFormats( it.value()->formats() );
-            auto input = track->clipAt( it.key() );
-            track->remove( track->clipIndexAt( it.key() ) );
-            track->insertAt( *input, startingFrame );
-            delete input;
-
+            track->move( it.key(), startingFrame );
             m_clips.erase( it );
             m_clips.insertMulti( startingFrame, clip );
             return ;