Remember best fit beween different image sizes

imagescrollareagl.cpp

@@ -260,6 +260,7 @@ ImageScrollAreaGL::ImageScrollAreaGL(QWidget *parent) : QWidget(parent)
     m_verticalScrollBar = new QScrollBar(Qt::Vertical, this);
     m_horizontalScrollBar = new QScrollBar(Qt::Horizontal, this);
     m_scale = 1.0f;
+    m_bestFit = false;
 
     layout->setSpacing(0);
     layout->addWidget(m_imageWidget, 0, 0);
@@ -280,6 +281,7 @@ void ImageScrollAreaGL::setImage(RawImage *image)
     m_imageWidget->setImage(image);
     m_imgWidth = image->width();
     m_imgHeight = image->height();
+    if(m_bestFit)bestFit();
     updateScrollbars();
 }
 
@@ -288,6 +290,7 @@ void ImageScrollAreaGL::setImage(const QPixmap &pixmap)
     m_imageWidget->setImage(pixmap);
     m_imgWidth = pixmap.width();
     m_imgHeight = pixmap.height();
+    if(m_bestFit)bestFit();
     updateScrollbars();
 }
 
@@ -333,6 +336,7 @@ void ImageScrollAreaGL::mousePressEvent(QMouseEvent *event)
 
 void ImageScrollAreaGL::wheelEvent(QWheelEvent *event)
 {
+    m_bestFit = false;
     if(event->angleDelta().y() != 0)
         zoom(event->angleDelta().y() / 1200.0f);
 }
@@ -351,15 +355,18 @@ void ImageScrollAreaGL::zoom(float delta)
 void ImageScrollAreaGL::zoomIn()
 {
     zoom(0.1f);
+    m_bestFit = false;
 }
 
 void ImageScrollAreaGL::zoomOut()
 {
     zoom(-0.1f);
+    m_bestFit = false;
 }
 
 void ImageScrollAreaGL::bestFit()
 {
+    m_bestFit = true;
     m_scale = std::min((float)m_imageWidget->width()/m_imgWidth, (float)m_imageWidget->height()/m_imgHeight);
     zoom(0.0f);
 }
@@ -368,6 +375,7 @@ void ImageScrollAreaGL::oneToOne()
 {
     m_scale = 1.0f;
     zoom(0.0f);
+    m_bestFit = false;
 }
 
 void ImageScrollAreaGL::scrollEvent()

imagescrollareagl.h

@@ -70,6 +70,7 @@ class ImageScrollAreaGL : public QWidget
     int m_imgWidth, m_imgHeight;
     QPoint m_lastPos;
     float m_scale;
+    bool m_bestFit;
 public:
     explicit ImageScrollAreaGL(QWidget *parent = nullptr);
     ~ImageScrollAreaGL();