view base/RangeMapper.cpp @ 492:23945cdd7161

* Update RDF query stuff again so as to set up a temporary datastore each time we want to query over an rdf file, instead of using rasqal against the file. Seems the only way to avoid threading and storage management issues when trying to load from a single-source file and perform queries against our main datastore at the same time. Maybe.
author Chris Cannam
date Mon, 24 Nov 2008 16:26:11 +0000
parents 9525c9d7e54d
children bdc9bb371a9f
line wrap: on
line source
/* -*- 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.
*/

#include "RangeMapper.h"

#include <cassert>
#include <cmath>

#include <iostream>

LinearRangeMapper::LinearRangeMapper(int minpos, int maxpos,
				     float minval, float maxval,
                                     QString unit, bool inverted) :
    m_minpos(minpos),
    m_maxpos(maxpos),
    m_minval(minval),
    m_maxval(maxval),
    m_unit(unit),
    m_inverted(inverted)
{
    assert(m_maxval != m_minval);
    assert(m_maxpos != m_minpos);
}

int
LinearRangeMapper::getPositionForValue(float value) const
{
    int position = m_minpos +
        lrintf(((value - m_minval) / (m_maxval - m_minval))
               * (m_maxpos - m_minpos));
    if (position < m_minpos) position = m_minpos;
    if (position > m_maxpos) position = m_maxpos;
//    std::cerr << "LinearRangeMapper::getPositionForValue: " << value << " -> "
//              << position << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", minval " << m_minval << ", maxval " << m_maxval << ")" << std::endl;
    if (m_inverted) return m_maxpos - position;
    else return position;
}

float
LinearRangeMapper::getValueForPosition(int position) const
{
    if (m_inverted) position = m_maxpos - position;
    float value = m_minval +
        ((float(position - m_minpos) / float(m_maxpos - m_minpos))
         * (m_maxval - m_minval));
    if (value < m_minval) value = m_minval;
    if (value > m_maxval) value = m_maxval;
//    std::cerr << "LinearRangeMapper::getValueForPosition: " << position << " -> "
//              << value << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", minval " << m_minval << ", maxval " << m_maxval << ")" << std::endl;
    return value;
}

LogRangeMapper::LogRangeMapper(int minpos, int maxpos,
                               float minval, float maxval,
                               QString unit, bool inverted) :
    m_minpos(minpos),
    m_maxpos(maxpos),
    m_unit(unit),
    m_inverted(inverted)
{
    convertMinMax(minpos, maxpos, minval, maxval, m_minlog, m_ratio);

    std::cerr << "LogRangeMapper: minpos " << minpos << ", maxpos "
              << maxpos << ", minval " << minval << ", maxval "
              << maxval << ", minlog " << m_minlog << ", ratio " << m_ratio
              << ", unit " << unit.toStdString() << std::endl;

    assert(m_maxpos != m_minpos);

    m_maxlog = (m_maxpos - m_minpos) / m_ratio + m_minlog;
}

void
LogRangeMapper::convertMinMax(int minpos, int maxpos,
                              float minval, float maxval,
                              float &minlog, float &ratio)
{
    static float thresh = powf(10, -10);
    if (minval < thresh) minval = thresh;
    minlog = log10f(minval);
    ratio = (maxpos - minpos) / (log10f(maxval) - minlog);
}

void
LogRangeMapper::convertRatioMinLog(float ratio, float minlog,
                                   int minpos, int maxpos,
                                   float &minval, float &maxval)
{
    minval = powf(10, minlog);
    maxval = powf(10, (maxpos - minpos) / ratio + minlog);
}

int
LogRangeMapper::getPositionForValue(float value) const
{
    int position = (log10(value) - m_minlog) * m_ratio + m_minpos;
    if (position < m_minpos) position = m_minpos;
    if (position > m_maxpos) position = m_maxpos;
//    std::cerr << "LogRangeMapper::getPositionForValue: " << value << " -> "
//              << position << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", ratio " << m_ratio << ", minlog " << m_minlog << ")" << std::endl;
    if (m_inverted) return m_maxpos - position;
    else return position;
}

float
LogRangeMapper::getValueForPosition(int position) const
{
    if (m_inverted) position = m_maxpos - position;
    float value = powf(10, (position - m_minpos) / m_ratio + m_minlog);
//    std::cerr << "LogRangeMapper::getValueForPosition: " << position << " -> "
//              << value << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", ratio " << m_ratio << ", minlog " << m_minlog << ")" << std::endl;
    return value;
}