Please create QML tutorial to show logical pixels usage

There was an article: http://blog.qt.digia.com/blog/2013/04/25/retina-display-support-for-mac-os-ios-and-x11/

That article tells us that there is a mechanism in Qt to design the application properly independent of deivce DPI. But not a single example, and still no examples on the internet how to achieve this.

Consider following example:
[label1][space][label2]

• label1 uses 9pt font
• space is 6px wide (for standard 96dpi monitor)
• label2 uses 9pt font

That will look ok on 96dpi monitor, but when launched on Retina or even 160dpi laptop - labels will be together, with 6px space almost invisible.

This can be solved by putting scaling factor into context and write all measurements in pt, but that's old way of doing it. The article about Retina display support suggests that there is a better way now in Qt, called logical pixels, but doesn't explain how to make application that uses logical pixels.

Please create a QML tutorial to show how to use logical pixels.