Chris@1068: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@1068: 
Chris@1068: /*
Chris@1068:     Sonic Visualiser
Chris@1068:     An audio file viewer and annotation editor.
Chris@1068:     Centre for Digital Music, Queen Mary, University of London.
Chris@1068:     This file copyright 2006-2016 Chris Cannam and QMUL.
Chris@1068:     
Chris@1068:     This program is free software; you can redistribute it and/or
Chris@1068:     modify it under the terms of the GNU General Public License as
Chris@1068:     published by the Free Software Foundation; either version 2 of the
Chris@1068:     License, or (at your option) any later version.  See the file
Chris@1068:     COPYING included with this distribution for more information.
Chris@1068: */
Chris@1068: 
Chris@1068: #include "ColourScale.h"
Chris@1068: 
Chris@1068: #include "base/AudioLevel.h"
Chris@1068: #include "base/LogRange.h"
Chris@1068: 
Chris@1068: #include <cmath>
Chris@1068: 
Chris@1068: int ColourScale::m_maxPixel = 255;
Chris@1068: 
Chris@1068: ColourScale::ColourScale(int colourMap,
Chris@1068: 			 Scale scale,
Chris@1068: 			 double minValue,
Chris@1068: 			 double maxValue,
Chris@1068: 			 double threshold,
Chris@1068: 			 double gain) :
Chris@1068:     m_mapper(colourMap, 1.f, double(m_maxPixel)),
Chris@1068:     m_scale(scale),
Chris@1068:     m_min(minValue),
Chris@1068:     m_max(maxValue),
Chris@1068:     m_threshold(threshold),
Chris@1068:     m_gain(gain)
Chris@1068: {
Chris@1068:     if (minValue >= maxValue) {
Chris@1068: 	throw std::logic_error("maxValue must be greater than minValue");
Chris@1068:     }
Chris@1068: 
Chris@1068:     m_mappedMin = m_min;
Chris@1068:     m_mappedMax = m_max;
Chris@1068: 
Chris@1068:     if (m_scale == LogColourScale) {
Chris@1068: 
Chris@1068: 	LogRange::mapRange(m_mappedMin, m_mappedMax);
Chris@1068: 	
Chris@1068:     } else if (m_scale == PlusMinusOneScale) {
Chris@1068: 	
Chris@1068: 	m_mappedMin = -1.0;
Chris@1068: 	m_mappedMax =  1.0;
Chris@1068: 
Chris@1068:     } else if (m_scale == AbsoluteScale) {
Chris@1068: 
Chris@1068: 	m_mappedMin = fabs(m_mappedMin);
Chris@1068: 	m_mappedMax = fabs(m_mappedMax);
Chris@1068: 	if (m_mappedMin >= m_mappedMax) {
Chris@1068: 	    std::swap(m_mappedMin, m_mappedMax);
Chris@1068: 	}
Chris@1068:     }
Chris@1068: 
Chris@1068:     if (m_mappedMin >= m_mappedMax) {
Chris@1068: 	throw std::logic_error("maxValue must be greater than minValue [after mapping]");
Chris@1068:     }
Chris@1068: }
Chris@1068: 
Chris@1068: int
Chris@1068: ColourScale::getPixel(double value)
Chris@1068: {
Chris@1068:     double maxPixF = m_maxPixel;
Chris@1068: 
Chris@1068:     if (m_scale == PhaseColourScale) {
Chris@1068: 	double half = (maxPixF - 1.f) / 2.f;
Chris@1068: 	return 1 + int((value * half) / M_PI + half);
Chris@1068:     }
Chris@1068:     
Chris@1068:     value *= m_gain;
Chris@1068: 
Chris@1068:     if (value < m_threshold) return 0;
Chris@1068: 
Chris@1068:     double mapped = value;
Chris@1068: 
Chris@1068:     if (m_scale == LogColourScale) {
Chris@1068: 	mapped = LogRange::map(value);
Chris@1068:     } else if (m_scale == PlusMinusOneScale) {
Chris@1068: 	if (mapped < -1.f) mapped = -1.f;
Chris@1068: 	if (mapped > 1.f) mapped = 1.f;
Chris@1068:     } else if (m_scale == AbsoluteScale) {
Chris@1068: 	if (mapped < 0.f) mapped = -mapped;
Chris@1068:     }
Chris@1068: 	
Chris@1068:     if (mapped < m_mappedMin) {
Chris@1068: 	mapped = m_mappedMin;
Chris@1068:     }
Chris@1068:     if (mapped > m_mappedMax) {
Chris@1068: 	mapped = m_mappedMax;
Chris@1068:     }
Chris@1068: 
Chris@1068:     double proportion = (mapped - m_mappedMin) / (m_mappedMax - m_mappedMin);
Chris@1068: 
Chris@1068:     int pixel = 0;
Chris@1068: 
Chris@1068:     if (m_scale == MeterColourScale) {
Chris@1068: 	pixel = AudioLevel::multiplier_to_preview(proportion, m_maxPixel-1) + 1;
Chris@1068:     } else {
Chris@1068: 	pixel = int(proportion * maxPixF) + 1;
Chris@1068:     }
Chris@1068: 
Chris@1068:     if (pixel > m_maxPixel) pixel = m_maxPixel;
Chris@1068:     if (pixel < 0) pixel = 0;
Chris@1068:     return pixel;
Chris@1068: }
Chris@1068: 
Chris@1068: QColor
Chris@1068: ColourScale::getColourForPixel(int pixel, int rotation)
Chris@1068: {
Chris@1068:     if (pixel < 0) {
Chris@1068: 	pixel = 0;
Chris@1068:     }
Chris@1068:     if (pixel > m_maxPixel) {
Chris@1068: 	pixel = m_maxPixel;
Chris@1068:     }
Chris@1068:     if (pixel == 0) {
Chris@1068: 	if (m_mapper.hasLightBackground()) {
Chris@1068: 	    return Qt::white;
Chris@1068: 	} else {
Chris@1068: 	    return Qt::black;
Chris@1068: 	}
Chris@1068:     } else {
Chris@1068: 	int target = int(pixel) + rotation;
Chris@1068: 	while (target < 1) target += m_maxPixel;
Chris@1068: 	while (target > m_maxPixel) target -= m_maxPixel;
Chris@1068: 	return m_mapper.map(double(target));
Chris@1068:     }
Chris@1068: }