NSScreen's visibleFrame using Quartz Display Services

I'm writing a cross-platform C++ library and one of the features I provide is an API for active monitor information, similar to QScreen. Looking at the QScreen source code I noticed that the folks at Qt are using both NSScreen and Quartz Display Services.

Since most of my library is written using Quartz I wanted to see if I can avoid mixing two API's and implement everything using Quartz. Using CGGetActiveDisplayList and CGDisplayBounds I'm most of the way there but I haven't found a way to implement [NSScreen visibleFrame]. Any way to this easily without getting into Objective-C, perhaps I overlooked something?