annotate base/RangeMapper.cpp @ 438:32c399d06374

* minor tidy
author Chris Cannam
date Thu, 07 Aug 2008 16:06:59 +0000
parents ca3b91119482
children 9525c9d7e54d
rev   line source
Chris@189 1 /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
Chris@189 2
Chris@189 3 /*
Chris@189 4 Sonic Visualiser
Chris@189 5 An audio file viewer and annotation editor.
Chris@189 6 Centre for Digital Music, Queen Mary, University of London.
Chris@202 7 This file copyright 2006 QMUL.
Chris@189 8
Chris@189 9 This program is free software; you can redistribute it and/or
Chris@189 10 modify it under the terms of the GNU General Public License as
Chris@189 11 published by the Free Software Foundation; either version 2 of the
Chris@189 12 License, or (at your option) any later version. See the file
Chris@189 13 COPYING included with this distribution for more information.
Chris@189 14 */
Chris@189 15
Chris@189 16 #include "RangeMapper.h"
Chris@189 17
Chris@189 18 #include <cassert>
Chris@189 19 #include <cmath>
Chris@189 20
Chris@189 21 #include <iostream>
Chris@189 22
Chris@189 23 LinearRangeMapper::LinearRangeMapper(int minpos, int maxpos,
Chris@189 24 float minval, float maxval,
Chris@189 25 QString unit) :
Chris@189 26 m_minpos(minpos),
Chris@189 27 m_maxpos(maxpos),
Chris@189 28 m_minval(minval),
Chris@189 29 m_maxval(maxval),
Chris@189 30 m_unit(unit)
Chris@189 31 {
Chris@189 32 assert(m_maxval != m_minval);
Chris@189 33 assert(m_maxpos != m_minpos);
Chris@189 34 }
Chris@189 35
Chris@189 36 int
Chris@189 37 LinearRangeMapper::getPositionForValue(float value) const
Chris@189 38 {
Chris@190 39 int position = m_minpos +
Chris@190 40 lrintf(((value - m_minval) / (m_maxval - m_minval))
Chris@190 41 * (m_maxpos - m_minpos));
Chris@189 42 if (position < m_minpos) position = m_minpos;
Chris@189 43 if (position > m_maxpos) position = m_maxpos;
Chris@241 44 // std::cerr << "LinearRangeMapper::getPositionForValue: " << value << " -> "
Chris@241 45 // << position << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", minval " << m_minval << ", maxval " << m_maxval << ")" << std::endl;
Chris@189 46 return position;
Chris@189 47 }
Chris@189 48
Chris@189 49 float
Chris@189 50 LinearRangeMapper::getValueForPosition(int position) const
Chris@189 51 {
Chris@190 52 float value = m_minval +
Chris@190 53 ((float(position - m_minpos) / float(m_maxpos - m_minpos))
Chris@190 54 * (m_maxval - m_minval));
Chris@189 55 if (value < m_minval) value = m_minval;
Chris@189 56 if (value > m_maxval) value = m_maxval;
Chris@241 57 // std::cerr << "LinearRangeMapper::getValueForPosition: " << position << " -> "
Chris@241 58 // << value << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", minval " << m_minval << ", maxval " << m_maxval << ")" << std::endl;
Chris@189 59 return value;
Chris@189 60 }
Chris@189 61
Chris@189 62 LogRangeMapper::LogRangeMapper(int minpos, int maxpos,
Chris@356 63 float minval, float maxval,
Chris@189 64 QString unit) :
Chris@189 65 m_minpos(minpos),
Chris@189 66 m_maxpos(maxpos),
Chris@189 67 m_unit(unit)
Chris@189 68 {
Chris@356 69 convertMinMax(minpos, maxpos, minval, maxval, m_minlog, m_ratio);
Chris@356 70
Chris@356 71 std::cerr << "LogRangeMapper: minpos " << minpos << ", maxpos "
Chris@356 72 << maxpos << ", minval " << minval << ", maxval "
Chris@356 73 << maxval << ", minlog " << m_minlog << ", ratio " << m_ratio
Chris@356 74 << ", unit " << unit.toStdString() << std::endl;
Chris@356 75
Chris@189 76 assert(m_maxpos != m_minpos);
Chris@189 77
Chris@189 78 m_maxlog = (m_maxpos - m_minpos) / m_ratio + m_minlog;
Chris@189 79 }
Chris@189 80
Chris@356 81 void
Chris@356 82 LogRangeMapper::convertMinMax(int minpos, int maxpos,
Chris@356 83 float minval, float maxval,
Chris@356 84 float &minlog, float &ratio)
Chris@356 85 {
Chris@356 86 static float thresh = powf(10, -10);
Chris@356 87 if (minval < thresh) minval = thresh;
Chris@356 88 minlog = log10f(minval);
Chris@356 89 ratio = (maxpos - minpos) / (log10f(maxval) - minlog);
Chris@356 90 }
Chris@356 91
Chris@356 92 void
Chris@356 93 LogRangeMapper::convertRatioMinLog(float ratio, float minlog,
Chris@356 94 int minpos, int maxpos,
Chris@356 95 float &minval, float &maxval)
Chris@356 96 {
Chris@356 97 minval = powf(10, minlog);
Chris@356 98 maxval = powf(10, (maxpos - minpos) / ratio + minlog);
Chris@356 99 }
Chris@356 100
Chris@189 101 int
Chris@189 102 LogRangeMapper::getPositionForValue(float value) const
Chris@189 103 {
Chris@341 104 int position = (log10(value) - m_minlog) * m_ratio + m_minpos;
Chris@189 105 if (position < m_minpos) position = m_minpos;
Chris@189 106 if (position > m_maxpos) position = m_maxpos;
Chris@356 107 std::cerr << "LogRangeMapper::getPositionForValue: " << value << " -> "
Chris@356 108 << position << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", ratio " << m_ratio << ", minlog " << m_minlog << ")" << std::endl;
Chris@189 109 return position;
Chris@189 110 }
Chris@189 111
Chris@189 112 float
Chris@189 113 LogRangeMapper::getValueForPosition(int position) const
Chris@189 114 {
Chris@189 115 float value = powf(10, (position - m_minpos) / m_ratio + m_minlog);
Chris@356 116 std::cerr << "LogRangeMapper::getValueForPosition: " << position << " -> "
Chris@356 117 << value << " (minpos " << m_minpos << ", maxpos " << m_maxpos << ", ratio " << m_ratio << ", minlog " << m_minlog << ")" << std::endl;
Chris@189 118 return value;
Chris@189 119 }
Chris@189 120