private void StopDragSelecting(Vector2 mousePos)
        {
            if (!_isDragSelecting)
            {
                return;
            }

            _isDragSelecting = false;

            FrameRange selectedRange = new FrameRange();
            bool       isSelectingTimelines;

            Rect selectionRect = GetDragSelectionRect(_dragSelectingStartPos, mousePos, out selectedRange, out isSelectingTimelines);

            if (!Event.current.shift && !Event.current.control)
            {
                SequenceEditor.DeselectAll();
            }

            for (int i = 0; i != Editors.Count; ++i)
            {
                Rect timelineRect = Editors[i].Rect;
                if (timelineRect.yMin >= selectionRect.yMax)
                {
                    break;
                }

                if (timelineRect.yMax <= selectionRect.yMin)
                {
                    continue;
                }

                for (int j = 0; j != Editors[i].Editors.Count; ++j)
                {
                    Rect trackRect = Editors[i].Editors[j].Rect;

                    if (trackRect.yMin >= selectionRect.yMax)
                    {
                        break;
                    }

                    if (trackRect.yMax <= selectionRect.yMin)
                    {
                        continue;
                    }

                    if (Event.current.control)
                    {
                        Editors[i].Editors[j].DeselectEvents(selectedRange);
                    }
                    else
                    {
                        Editors[i].Editors[j].SelectEvents(selectedRange);
                    }
                }
            }
        }