title: Qt::AA_EnableHighDpiScaling messes up screen geometry size in 4K Monitor at 4K Resolution
body: <p>I have a QT application that I need to run both on low and high resolution monitors. I'm using </p>
  
  <pre><code>QApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
  </code></pre>
  
  <p>to set the scaling of the Qt Window. </p>
  
  <p>And my current resolution from my 4K monitor is 3840 * 2160. I'm running windows. Now I'm trying get the current screen size with this.</p>
  
  <pre><code>QDesktopWidget qdw;
  QRect mainScreenSize = qdw.screenGeometry(0);
  
  int height1 = mainScreenSize.height();
  int width1 = mainScreenSize.width();
  std::cout &lt;&lt; width1 &lt;&lt; "\n";
  std::cout &lt;&lt; height1 &lt;&lt; "\n";
  </code></pre>
  
  <p>But this prints out 1920 * 1080. It does this only for 3840 * 2160 which is the full resolution for the monitor and this happens only when Qt::AA_EnableHighDpiScaling this is enabled. </p>
  
  <p>If HighDpiScaling is not enabled, then it prints every single resolution perfectly be it anything from 1920 * 1080 or 2560 * 1440 or whatever!</p>
  
  <p>I need to get the actual screen size with EnableHighDpiScaling enabled, so I can scale my GL screen based on the current screen resolution.</p>
  
  <p>Thank you.</p>