view widgets/LevelPanWidget.h @ 959:2633a1d73e39

Address #1214, layer import produces wrong layer type. We needed a more principled approach to making sure the format gets updated properly and the dialog elements are consistent (basically separating making the dialog elements consistent from subsequently updating the format). This change should provide that, though there may be gotchas still.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef LEVEL_PAN_WIDGET_H
#define LEVEL_PAN_WIDGET_H

#include <QWidget>

/**
 * A simple widget for coarse level and pan control.
 */

class LevelPanWidget : public QWidget
{
    Q_OBJECT

public:
    LevelPanWidget(QWidget *parent = 0);
    ~LevelPanWidget();
    
    /// Return level as a gain value in the range [0,1]
    float getLevel() const; 
    
    /// Return pan as a value in the range [-1,1]
    float getPan() const;

    /// Find out whether the widget is editable
    bool isEditable() const;

    /// Discover whether the level range includes muting or not
    bool includesMute() const;

    /// Draw a suitably sized copy of the widget's contents to the given device
    void renderTo(QPaintDevice *, QRectF, bool asIfEditable) const;

    QSize sizeHint() const;
                                               
public slots:
    /// Set level in the range [0,1] -- will be rounded
    void setLevel(float);

    /// Set pan in the range [-1,1] -- will be rounded
    void setPan(float);

    /// Specify whether the widget is editable or read-only (default editable)
    void setEditable(bool);

    /// Specify whether the level range should include muting or not
    void setIncludeMute(bool);
    
signals:
    void levelChanged(float);
    void panChanged(float);

protected:
    virtual void mousePressEvent(QMouseEvent *ev);
    virtual void mouseMoveEvent(QMouseEvent *ev);
    virtual void mouseReleaseEvent(QMouseEvent *ev);
    virtual void wheelEvent(QWheelEvent *ev);
    virtual void paintEvent(QPaintEvent *ev);

    void emitLevelChanged();
    void emitPanChanged();
    
    int m_level;
    int m_pan;
    bool m_editable;
    bool m_includeMute;

    QSizeF cellSize(QRectF) const;
    QPointF cellCentre(QRectF, int level, int pan) const;
    QSizeF cellLightSize(QRectF) const;
    QRectF cellLightRect(QRectF, int level, int pan) const;
    double thinLineWidth(QRectF) const;
    void toCell(QRectF, QPointF loc, int &level, int &pan) const;
};

#endif