#include <QApplication>
#include <QGuiApplication>

#include <QWidget>
#include <QRadioButton>

#include <QGridLayout>


int main(int argc, char *argv[])
{ // High-DPI scale factor rounding
  // when rounding down or up for screen with natural non-integer device pixel ratio,
  // the radio buttons look ugly (looks like a poorly scaled bitmap).
//  QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::Floor);
  QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::Ceil);


  // application
  QApplication app(argc,argv);

  // tested on 4K screen under Windows 10 with a device pixel ratio 1.5
  QRadioButton *radiobutton1 = new QRadioButton(),
               *radiobutton2 = new QRadioButton();
  radiobutton1->setChecked(true);
  radiobutton2->setChecked(false);

  QGridLayout *layout = new QGridLayout();
  layout->addWidget(radiobutton1,0,0);
  layout->addWidget(radiobutton2,1,0);

  QWidget widget;
  widget.setLayout(layout);
  widget.show();

  return QApplication::exec();
}