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++ // Copyright (C) 2016 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++
++ #ifndef KNOB_H
++ #define KNOB_H
++
++ #include <QGraphicsItem>
++
++ class Knob : public QGraphicsEllipseItem
++ {
++ public:
++ Knob();
++
++ bool sceneEvent(QEvent *event) override;
++ };
++
++ #endif // KNOB_H