Add STFSlider

stfslider.cpp

@@ -0,0 +1,98 @@
+#include "stfslider.h"
+#include <cmath>
+#include <QPainter>
+#include <QPaintEvent>
+
+STFSlider::STFSlider(QWidget *parent) : QWidget(parent)
+{
+    setMinimumHeight(15);
+    setMouseTracking(true);
+    m_blackPoint = 0;
+    m_midPoint = 0.5;
+    m_whitePoint = 1;
+    m_grabbed = -1;
+}
+
+void STFSlider::paintEvent(QPaintEvent *event)
+{
+    QPainter painter(this);
+    QRect rect = event->rect();
+    qreal w = rect.width() - 1;
+    qreal h = rect.height();
+    QLinearGradient gradient(rect.topLeft(), rect.topRight());
+    gradient.setColorAt(0, Qt::black);
+    for(int i=1; i<=32; i++)
+    {
+        qreal p = i/32.0f;
+        qreal c = std::pow(p, 1.0/2.2)*255;
+        gradient.setColorAt(p, QColor(c, c, c));
+    }
+
+    QPainterPath tick(QPointF(0, 0));
+    tick.lineTo(0, h - 5);
+    tick.lineTo(-5, h);
+    tick.lineTo(5, h);
+    tick.lineTo(0, h - 5);
+
+    painter.setBrush(gradient);
+    painter.setPen(Qt::NoPen);
+    painter.drawRect(rect);
+
+    auto drawTick = [&](qreal p)
+    {
+        painter.setPen(p < 0.4 ? Qt::white : Qt::black);
+        painter.resetTransform();
+        painter.translate(w*p, 0);
+        painter.drawPath(tick);
+    };
+
+    painter.setBrush(Qt::NoBrush);
+    drawTick(m_blackPoint);
+    drawTick(m_blackPoint + (m_whitePoint - m_blackPoint) * m_midPoint);
+    drawTick(m_whitePoint);
+}
+
+void STFSlider::mouseMoveEvent(QMouseEvent *event)
+{
+    if(std::abs(m_blackPoint*width() - event->x()) < 5 ||
+            std::abs((m_blackPoint + (m_whitePoint - m_blackPoint) * m_midPoint)*width() - event->x()) < 5 ||
+            std::abs(m_whitePoint*width() - event->x()) < 5)
+        setCursor(Qt::SplitHCursor);
+    else
+        unsetCursor();
+
+    switch(m_grabbed)
+    {
+    case 0:
+        m_blackPoint = (qreal)event->x()/width();
+        m_whitePoint = std::max(m_whitePoint, m_blackPoint);
+        break;
+    case 1:
+        m_midPoint = ((qreal)event->x()/width() - m_blackPoint) / (m_whitePoint - m_blackPoint);
+        m_midPoint = std::max(std::min(m_midPoint, 1.0f), 0.0f);
+        break;
+    case 2:
+        m_whitePoint = (qreal)event->x()/width();
+        m_blackPoint = std::min(m_blackPoint, m_whitePoint);
+        break;
+    }
+    if(m_grabbed >= 0)
+        repaint();
+}
+
+void STFSlider::mousePressEvent(QMouseEvent *event)
+{
+    if(std::abs((m_blackPoint + (m_whitePoint - m_blackPoint) * m_midPoint)*width() - event->x()) < 5)
+        m_grabbed = 1;
+    else if(std::abs(m_blackPoint*width() - event->x()) < 5)
+        m_grabbed = 0;
+    else if(std::abs(m_whitePoint*width() - event->x()) < 5)
+        m_grabbed = 2;
+    else
+        m_grabbed = -1;
+}
+
+void STFSlider::mouseReleaseEvent(QMouseEvent *)
+{
+    m_grabbed = -1;
+}

stfslider.h

@@ -0,0 +1,23 @@
+#ifndef STFSLIDER_H
+#define STFSLIDER_H
+
+#include <QObject>
+#include <QWidget>
+
+class STFSlider : public QWidget
+{
+    Q_OBJECT
+    float m_blackPoint;
+    float m_midPoint;
+    float m_whitePoint;
+    int m_grabbed;
+public:
+    explicit STFSlider(QWidget *parent = nullptr);
+protected:
+    void paintEvent(QPaintEvent *event) override;
+    void mouseMoveEvent(QMouseEvent *event) override;
+    void mousePressEvent(QMouseEvent *event) override;
+    void mouseReleaseEvent(QMouseEvent *) override;
+};
+
+#endif // STFSLIDER_H

stretchpanel.cpp

@@ -1,7 +1,8 @@
 #include "stretchpanel.h"
 #include <QVBoxLayout>
-#include "imageringlist.h"
 #include <QDebug>
+#include "imageringlist.h"
+#include "stfslider.h"
 
 StretchPanel::StretchPanel(QWidget *parent) : QWidget(parent)
 {
@@ -12,6 +13,8 @@ StretchPanel::StretchPanel(QWidget *parent) : QWidget(parent)
     m_highSlider = new QSlider(Qt::Horizontal, this);
     m_paramSlider = new QSlider(Qt::Horizontal, this);
 
+    STFSlider *stfslider = new STFSlider(this);
+
     m_lowSlider->setRange(0, UINT16_MAX);
     m_lowSlider->setPageStep(512);
     m_highSlider->setRange(0, UINT16_MAX);
@@ -27,6 +30,7 @@ StretchPanel::StretchPanel(QWidget *parent) : QWidget(parent)
     layout->addWidget(m_highSlider);
     layout->addWidget(m_paramSlider);
     layout->addWidget(m_stretchSelect);
+    layout->addWidget(stfslider);
 
     connect(m_lowSlider, SIGNAL(valueChanged(int)), this, SIGNAL(lowChanged(int)));
     connect(m_highSlider, SIGNAL(valueChanged(int)), this, SIGNAL(highChanged(int)));

tenmon.pro

@@ -33,7 +33,9 @@ SOURCES += main.cpp\
     starfit.cpp \
     imagescrollareagl.cpp \
     stretchpanel.cpp \
-    rawimage.cpp
+    rawimage.cpp \
+    stfslider.cpp
+
 
 HEADERS  += mainwindow.h \
     filesystemwidget.h \
@@ -45,7 +47,8 @@ HEADERS  += mainwindow.h \
     rawimage.h \
     starfit.h \
     imagescrollareagl.h \
-    stretchpanel.h
+    stretchpanel.h \
+    stfslider.h
 
 RESOURCES += \
     resources.qrc