Qt Improvements Forthcoming For HiDPI Displays

The upcoming Qt 5.4 release betters the support for HiDPI monitors -- displays like the Retina MacBook Pro and others with high pixel densities -- though Qt5 developers need to make some changes to their code to take advantage of these improvements.

For those using HiDPI displays or if you're just a Qt5 developer looking to ensure your application is very portable, with Qt 5.4 there is the concept of device independent pixels with a scaling factor to accomodate devices at non-standard pixel densities.

Qt5 applications need to opt into using high DPI pixmap support so their users can take advantage of such features. Those with these high-DPI displays can set the DPI under their system settings and also adjust the pixel ratio with the QT_DEVICE_PIXEL_RATIO environment variable.

More details on this work can be found via David Edmundson's blog.