Files
tenmon/histogram.cpp
T
2023-11-14 12:04:55 +01:00

85 lines
2.4 KiB
C++

#include "histogram.h"
#include <cmath>
#include <algorithm>
#include <QPainter>
#include <QDebug>
Histogram::Histogram(QWidget *parent) : QWidget(parent)
{
setStyleSheet("QWidget { background: white; color: black; } ");
}
void Histogram::imageLoaded(Image *img)
{
if(img && img->rawImage())
{
m_histogram = img->rawImage()->imageStats().m_histogram;
m_points.clear();
update();
}
}
void Histogram::paintEvent(QPaintEvent *)
{
QPainter painter(this);
painter.fillRect(rect(), Qt::black);
uint h = height();
uint w = width();
if(m_histogram.size())
{
if(m_points.size() != w)
{
m_points.clear();
for(uint64_t i = 0; i < w; i++)
{
uint32_t sum = 0;
uint64_t start = i * m_histogram.size() / w;
uint64_t end =(i+1) * m_histogram.size() / w;
for(uint64_t o = start; o < end; o++)
sum += m_histogram[o];
if(start != end)
m_points.push_back(sum);
}
float scale = *std::max_element(m_points.begin(), m_points.end());
if(m_log)
{
scale = std::log(scale);
std::for_each(m_points.begin(), m_points.end(), [scale](float &x){ x = (x > 0 ? std::log(x) : 0.0f) / scale; });
}
else
{
std::for_each(m_points.begin(), m_points.end(), [scale](float &x){ x /= scale; });
}
}
std::vector<QPointF> points;
points.push_back(QPointF(0, h));
for(size_t i = 0; i < m_points.size(); i++)
{
points.push_back(QPointF((float)i * w / m_points.size(), h - m_points[i] * h));
}
points.push_back(QPoint(w, h));
painter.setBrush(Qt::gray);
painter.setPen(Qt::white);
painter.drawPolygon(&points[0], points.size());
}
QStyleOptionButton button;
button.initFrom(this);
button.state = m_log ? QStyle::State_On : QStyle::State_Off;
button.text = tr("Logarithmic scale");
button.rect = style()->subElementRect(QStyle::SE_CheckBoxClickRect, &button, this);
button.rect.moveTop(0);
button.rect.moveRight(w);
style()->drawControl(QStyle::CE_CheckBox, &button, &painter, this);
}
void Histogram::mouseReleaseEvent(QMouseEvent *)
{
m_log = !m_log;
m_points.clear();
update();
}