qt: Does not work well with HiDPI displays on Linux
@amorenoc see attached screenshot. How does it work on OSX with Retina displays?
It looks like parts of the UI are scaled properly, other parts not.

@sdroege retina displays looks fine, weird that in a HiDPI screen it's upscaled (since I am using device independent sizes for the icons). FWIW looks like there will be better support for cross-platform HiDPI: http://lists.qt-project.org/pipermail/development/2015-June/021631.html
Well, the icons are upscaled and correct and so is the text (0:00). What is wrong is the scale of the window and the toolbar. They would have to be scaled by two too, then everything would look correct :)
Do you specify things in device pixels somewhere and could specify it in "visual pixels" instead?
@sdroege yes, I am specifying fonts in points and other sizes in pixels, so I will have to fix that :) But still puzzles me that I am not seeing this issue since I use a MacBook Pro with Retina display.
this link explains why we are seeing different results: http://blog.qt.io/blog/2013/04/25/retina-display-support-for-mac-os-ios-and-x11/