annotate base/RangeMapper.h @ 266:2268963dabd1

* FFT: fix invalid write of normalisation factor in compact mode of disc cache
* FFT: fix range problem for normalisation factor in compact mode (it was
  stored as an unsigned scaled from an assumed float range of 0->1, which
  is not very plausible and not accurate enough even if true -- use a float
  instead)
* Spectrogram: fix vertical zoom behaviour for log frequency spectrograms:
  make the thing in the middle of the display remain in the middle after zoom
* Overview widget: don't update the detailed waveform if still decoding the
  audio file (too expensive to do all those redraws)

/* -*- 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 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 _RANGE_MAPPER_H_
#define _RANGE_MAPPER_H_

#include <QString>


class RangeMapper 
{
public:
    virtual ~RangeMapper() { }
    virtual int getPositionForValue(float value) const = 0;
    virtual float getValueForPosition(int position) const = 0;
    virtual QString getUnit() const { return ""; }
};


class LinearRangeMapper : public RangeMapper
{
public:
    LinearRangeMapper(int minpos, int maxpos,
                      float minval, float maxval,
                      QString unit = "");
    
    virtual int getPositionForValue(float value) const;
    virtual float getValueForPosition(int position) const;

    virtual QString getUnit() const { return m_unit; }

protected:
    int m_minpos;
    int m_maxpos;
    float m_minval;
    float m_maxval;
    QString m_unit;
};


class LogRangeMapper : public RangeMapper
{
public:
    LogRangeMapper(int minpos, int maxpos,
                   float ratio, float minlog,
                   QString m_unit = "");

    virtual int getPositionForValue(float value) const;
    virtual float getValueForPosition(int position) const;

    virtual QString getUnit() const { return m_unit; }

protected:
    int m_minpos;
    int m_maxpos;
    float m_ratio;
    float m_minlog;
    float m_maxlog;
    QString m_unit;
};


#endif