view layer/PianoScale.h @ 1271:d967e21fe995

Avoid crash when scrolling with an empty layer open

/* -*- 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 file copyright 2006-2013 Chris Cannam and QMUL.
    
    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 PIANO_SCALE_H
#define PIANO_SCALE_H

#include <QRect>

class QPainter;
class LayerGeometryProvider;

class PianoScale
{
public:
    void paintPianoVertical
    (LayerGeometryProvider *v, QPainter &paint, QRect rect, double minf, double maxf);

    class HorizontalScaleProvider {
    public:
        virtual double getFrequencyForX(const LayerGeometryProvider *, double x) const = 0;
        virtual double getXForFrequency(const LayerGeometryProvider *, double freq) const = 0;
    };
    
    void paintPianoHorizontal
    (LayerGeometryProvider *v, const HorizontalScaleProvider *p,
     QPainter &paint, QRect rect);
};

#endif