Restructure drag-related variables to have them defined more clearly

Also restore an ability to use Ctrl or Shift for horizontal/vertical drag of lines

libmscore/beam.cpp

@@ -2565,7 +2565,7 @@ void Beam::initBeamEditData(EditData& ed)
       bed->editFragment = 0;
       ed.addData(bed);
 
-      QPointF pt(ed.startMove - pagePos());
+      QPointF pt(ed.normalizedStartMove - pagePos());
       qreal ydiff = 100000000.0;
       int idx = (_direction == Direction::AUTO || _direction == Direction::DOWN) ? 0 : 1;
       int i = 0;

libmscore/box.cpp

@@ -603,7 +603,7 @@ Element* Box::drop(EditData& data)
 QRectF HBox::drag(EditData& data)
       {
       QRectF r(canvasBoundingRect());
-      qreal diff = data.delta.x();
+      qreal diff = data.evtDelta.x();
       qreal x1   = offset().x() + diff;
       if (parent()->type() == ElementType::VBOX) {
             VBox* vb = toVBox(parent());

libmscore/dynamic.cpp

@@ -359,15 +359,18 @@ QRectF Dynamic::drag(EditData& ed)
       if (km != (Qt::ShiftModifier | Qt::ControlModifier)) {
             int si       = staffIdx();
             Segment* seg = segment();
-            score()->dragPosition(ed.pos, &si, &seg);
+            score()->dragPosition(canvasPos(), &si, &seg);
             if (seg != segment() || staffIdx() != si) {
+                  const QPointF oldOffset = offset();
                   QPointF pos1(canvasPos());
                   score()->undo(new ChangeParent(this, seg, si));
                   setOffset(QPointF());
                   layout();
                   QPointF pos2(canvasPos());
-                  setOffset(pos1 - pos2);
+                  const QPointF newOffset = pos1 - pos2;
-                  ed.startMove = pos2;
+                  setOffset(newOffset);
+                  ElementEditData* eed = ed.getData(this);
+                  eed->initOffset += newOffset - oldOffset;
                   }
             }
       return f;

libmscore/element.cpp

@@ -1946,6 +1946,7 @@ void Element::startDrag(EditData& ed)
       eed->e = this;
       eed->pushProperty(Pid::OFFSET);
       eed->pushProperty(Pid::AUTOPLACE);
+      eed->initOffset = offset();
       ed.addData(eed);
       if (ed.modifiers & Qt::AltModifier)
             setAutoplace(false);
@@ -1963,8 +1964,11 @@ QRectF Element::drag(EditData& ed)
 
       const QRectF r0(canvasBoundingRect());
 
-      qreal x = ed.delta.x();
+      const ElementEditData* eed = ed.getData(this);
-      qreal y = ed.delta.y();
+
+      const QPointF offset0 = ed.moveDelta + eed->initOffset;
+      qreal x = offset0.x();
+      qreal y = offset0.y();
 
       qreal _spatium = spatium();
       if (ed.hRaster) {

libmscore/element.h

@@ -120,9 +120,12 @@ class EditData {
 
       QPointF pos;
       QPointF startMove;
+      QPointF normalizedStartMove; ///< Introduced for transition of drag logic. Don't use in new code.
       QPoint  startMovePixel;
       QPointF lastPos;
-      QPointF delta;
+      QPointF delta; ///< This property is deprecated, use evtDelta or moveDelta instead. In normal drag equals to moveDelta, in edit drag - to evtDelta
+      QPointF evtDelta; ///< Mouse offset for the last mouse move event
+      QPointF moveDelta; ///< Mouse offset from the start of mouse move
       bool hRaster                     { false };
       bool vRaster                     { false };
 
@@ -535,6 +538,7 @@ class ElementEditData {
    public:
       Element* e;
       QList<PropertyData> propertyData;
+      QPointF initOffset; ///< for dragging: difference between actual offset and editData.moveDelta
 
       virtual ~ElementEditData() = default;
       void pushProperty(Pid pid) { propertyData.push_back(PropertyData({ pid, e->getProperty(pid), e->propertyFlags(pid) })); }

libmscore/line.cpp

@@ -547,7 +547,7 @@ QVector<QLineF> LineSegment::dragAnchorLines() const
 
 QRectF LineSegment::drag(EditData& ed)
       {
-      setOffset(offset() + (ed.pos - ed.lastPos));
+      setOffset(offset() + ed.evtDelta);
       setOffsetChanged(true);
 
       if (isStyled(Pid::OFFSET))

libmscore/note.cpp

@@ -2424,7 +2424,7 @@ QRectF Note::drag(EditData& ed)
             return QRectF();
             }
 
-      QPointF delta = ed.pos - ed.lastPos;
+      QPointF delta = ed.evtDelta;
       noteEditData->delta = delta;
 
       if (noteEditData->mode == NoteEditData::EditMode_Undefined) {
@@ -2468,11 +2468,11 @@ void Note::editDrag(EditData& editData)
       if (ch->notes().size() == 1) {
             // if the chord contains only this note, then move the whole chord
             // including stem, flag etc.
-            ch->undoChangeProperty(Pid::OFFSET, ch->offset() + offset() + editData.delta);
+            ch->undoChangeProperty(Pid::OFFSET, ch->offset() + offset() + editData.evtDelta);
             setOffset(QPointF());
             }
       else
-            setOffset(offset() + editData.delta);
+            setOffset(offset() + editData.evtDelta);
 
       triggerLayout();
       }
@@ -2495,7 +2495,7 @@ void Note::verticalDrag(EditData &ed)
       qreal _spatium      = spatium();
       bool tab            = st->isTabStaff();
       qreal step          = _spatium * (tab ? st->lineDistance().val() : 0.5);
-      int lineOffset      = lrint(ed.delta.y() / step);
+      int lineOffset      = lrint(ed.moveDelta.y() / step);
 
       if (tab) {
             const StringData* strData = staff()->part()->instrument()->stringData();
@@ -2582,7 +2582,7 @@ void Note::horizontalDrag(EditData &ed)
           (((ed.buttons & Qt::LeftButton) && !(ed.modifiers & Qt::ControlModifier))
            || (ed.modifiers & Qt::ShiftModifier))) {
 
-            if (ed.delta.x() < 0)
+            if (ed.moveDelta.x() < 0)
                   normalizeLeftDragDelta(seg, ed, ned);
             }
 

mscore/dragelement.cpp

@@ -31,7 +31,7 @@ void ScoreView::startDrag()
       {
       editData.grips = 0;
       editData.clearData();
-      editData.startMove  -= editData.element->offset();
+      editData.normalizedStartMove = editData.startMove - editData.element->offset();
 
       _score->startCmd();
 
@@ -47,21 +47,29 @@ void ScoreView::startDrag()
 
 void ScoreView::doDragElement(QMouseEvent* ev)
       {
-      QPointF delta = toLogical(ev->pos()) - editData.startMove;
+      const QPointF logicalPos = toLogical(ev->pos());
+      QPointF delta = logicalPos - editData.normalizedStartMove;
+      QPointF evtDelta = logicalPos - editData.pos;
 
       TourHandler::startTour("autoplace-tour");
 
       QPointF pt(delta);
-      if (qApp->keyboardModifiers() == Qt::ShiftModifier)
+      if (qApp->keyboardModifiers() == Qt::ShiftModifier) {
-            pt.setX(editData.element->offset().x());
+            pt.setX(editData.delta.x());
-      else if (qApp->keyboardModifiers() == Qt::ControlModifier)
+            evtDelta.setX(0.0);
-            pt.setY(editData.element->offset().y());
+            }
+      else if (qApp->keyboardModifiers() == Qt::ControlModifier) {
+            pt.setY(editData.delta.y());
+            evtDelta.setY(0.0);
+            }
 
       editData.lastPos = editData.pos;
       editData.hRaster = mscore->hRaster();
       editData.vRaster = mscore->vRaster();
       editData.delta   = pt;
-      editData.pos     = toLogical(ev->pos());
+      editData.moveDelta = pt + (editData.normalizedStartMove - editData.startMove); // TODO: restructure
+      editData.evtDelta = evtDelta;
+      editData.pos     = logicalPos;
 
       const Selection& sel = _score->selection();
       const bool filterType = sel.isRange();