handle transition track movement

Only allow transitions to move tracks if their attached blocks are moving
with them.

app/widget/timelinewidget/tool/pointer.cpp

@@ -230,7 +230,7 @@ void TimelineWidget::PointerTool::MouseReleaseInternal(TimelineViewMouseEvent *e
     }
 
     const TrackReference& track_ref = ghost->GetAdjustedTrack();
-    TrackOutput* track = parent()->GetTrackFromReference(track_ref);
+    //TrackOutput* track = parent()->GetTrackFromReference(track_ref);
 
     Block* b = Node::ValueToPtr<Block>(ghost->data(TimelineViewGhostItem::kAttachedBlock));
 
@@ -267,12 +267,13 @@ void TimelineWidget::PointerTool::MouseReleaseInternal(TimelineViewMouseEvent *e
       }
     }
 
-    // Remove transitions that have been reduced to zero length
-    if (b->type() == Block::kTransition) {
+    if (b->type() == Block::kTransition && ghost->AdjustedLength() == 0) {
+      // Remove transitions that have been reduced to zero length
       new NodeRemoveCommand(static_cast<NodeGraph*>(b->parent()),
                             {b},
                             command);
     } else {
+      // Normal block placement
       new TrackPlaceBlockCommand(parent()->timeline_node_->track_list(track_ref.type()),
                                  track_ref.index(),
                                  b,
@@ -478,19 +479,33 @@ void TimelineWidget::PointerTool::InitiateGhosts(TimelineViewBlockItem* clicked_
       }
 
       if (block) {
-        AddGhostFromBlock(block, clip_item->Track(), block_mode);
+        TimelineViewGhostItem* ghost = AddGhostFromBlock(block, clip_item->Track(), block_mode);
 
         if (block->type() == Block::kTransition) {
           TransitionBlock* transition = static_cast<TransitionBlock*>(block);
 
+          bool transition_can_move_tracks = false;
+
           // Create a rolling effect with the attached block
-          if (transition->connected_in_block() && (block_mode == Timeline::kTrimOut || block_mode == Timeline::kMove)) {
-            AddGhostFromBlock(transition->connected_in_block(), clip_item->Track(), Timeline::kTrimIn);
+          if (transition->connected_in_block()) {
+            if (parent()->block_items_.value(transition->connected_in_block())->isSelected()) {
+              // We'll be moving this item too, no need to create a ghost for it here
+              transition_can_move_tracks = true;
+            } else if (block_mode == Timeline::kTrimOut || block_mode == Timeline::kMove) {
+              AddGhostFromBlock(transition->connected_in_block(), clip_item->Track(), Timeline::kTrimIn);
+            }
           }
 
-          if (transition->connected_out_block() && (block_mode == Timeline::kTrimIn || block_mode == Timeline::kMove)) {
-            AddGhostFromBlock(transition->connected_out_block(), clip_item->Track(), Timeline::kTrimOut);
+          if (transition->connected_out_block()) {
+            if (parent()->block_items_.value(transition->connected_in_block())->isSelected()) {
+                // We'll be moving this item too, no need to create a ghost for it here
+              transition_can_move_tracks = true;
+            } else if (block_mode == Timeline::kTrimIn || block_mode == Timeline::kMove) {
+              AddGhostFromBlock(transition->connected_out_block(), clip_item->Track(), Timeline::kTrimOut);
+            }
           }
+
+          ghost->SetCanMoveTracks(transition_can_move_tracks);
         }
       }
     }

app/widget/timelinewidget/tool/tool.cpp

@@ -107,7 +107,7 @@ rational TimelineWidget::Tool::ValidateFrameMovement(rational movement, const QV
     if (block && block->type() == Block::kTransition) {
       TransitionBlock* transition = static_cast<TransitionBlock*>(block);
 
-      // Daul transitions are only allowed to move so that neither of their offsets are < 0
+      // Dual transitions are only allowed to move so that neither of their offsets are < 0
       if (transition->connected_in_block() && transition->connected_out_block()) {
         if (movement > transition->out_offset()) {
           movement = transition->out_offset();
@@ -131,13 +131,19 @@ rational TimelineWidget::Tool::ValidateFrameMovement(rational movement, const QV
 int TimelineWidget::Tool::ValidateTrackMovement(int movement, const QVector<TimelineViewGhostItem *> ghosts)
 {
   foreach (TimelineViewGhostItem* ghost, ghosts) {
-    // Prevents any ghosts from going to a non-existent negative track
-    if (ghost->Track().index() + movement < 0) {
-      if (ghost->mode() != Timeline::kMove) {
-        continue;
-      }
+    if (ghost->mode() != Timeline::kMove) {
+      continue;
+    }
 
+    if (!ghost->CanMoveTracks()) {
+
+      movement = 0;
+
+    } else if (ghost->Track().index() + movement < 0) {
+
+      // Prevents any ghosts from going to a non-existent negative track
       movement = -ghost->Track().index();
+
     }
   }
 

app/widget/timelinewidget/view/timelineviewghostitem.cpp

@@ -27,7 +27,8 @@ TimelineViewGhostItem::TimelineViewGhostItem(QGraphicsItem *parent) :
   track_adj_(0),
   stream_(nullptr),
   mode_(Timeline::kNone),
-  can_have_zero_length_(true)
+  can_have_zero_length_(true),
+  can_move_tracks_(true)
 {
   SetInvisible(false);
 }
@@ -50,11 +51,21 @@ TimelineViewGhostItem *TimelineViewGhostItem::FromBlock(Block *block, const Trac
   return ghost;
 }
 
-bool TimelineViewGhostItem::CanHaveZeroLength()
+bool TimelineViewGhostItem::CanHaveZeroLength() const
 {
   return can_have_zero_length_;
 }
 
+bool TimelineViewGhostItem::CanMoveTracks() const
+{
+  return can_move_tracks_;
+}
+
+void TimelineViewGhostItem::SetCanMoveTracks(bool e)
+{
+  can_move_tracks_ = e;
+}
+
 void TimelineViewGhostItem::SetInvisible(bool invisible)
 {
   setBrush(Qt::NoBrush);

app/widget/timelinewidget/view/timelineviewghostitem.h

@@ -44,7 +44,10 @@ public:
 
   static TimelineViewGhostItem* FromBlock(Block *block, const TrackReference &track, int y, int height);
 
-  bool CanHaveZeroLength();
+  bool CanHaveZeroLength() const;
+
+  bool CanMoveTracks() const;
+  void SetCanMoveTracks(bool e);
 
   void SetInvisible(bool invisible);
 
@@ -99,6 +102,7 @@ private:
   Timeline::MovementMode mode_;
 
   bool can_have_zero_length_;
+  bool can_move_tracks_;
 };
 
 #endif // TIMELINEVIEWGHOSTITEM_H