But for screens that do report accurately we shouldn't need to ask for calibration (or at least a calibration step would be simpler).
Either way (changing
in to be real, or adding a new "real" units) I'd be happy, as long as there was just some way.
It's prevalent enough that "native" framework provide ways of getting the actual values we seek. For example, the Qt project provides a
Screen class that lets you get the device's actual pixel density (among other APIs for getting EDID info, plus it's a C++ framework so we can also just get EDID info from displays using the OS APIs). I can draw things on the screen using real-world sizes in Qt.
Yes!! Being able to specify display-size-independent design on any device using real-world units would be incredibly nice! I was able to do this using Qt. The web needs this too.
Imagine a designer who designs books. In many cases of book design, the measurements for things like font size and book size are probably based on real-world units (I'm guessing, but my guess is probably correct in many cases), since the thing being made is a real-world thing (nothing digital). We should be able to do the same with digital designs if the hardware allows it (i.e. if the hardware supplies EDID info).
Besides, even if not all displays reported accurate info, if it was a mere fact that the "web platform" had such things s a way to report actual screen metrics, then there would be a huge encouragement onto display manufacturers to provide such useful information, so it seems to me that adding such a feature to browsers is a good thing anyway, even if displays aren't currently accurate. For displays that are not accurate, it's easy to use the current system as a fallback anyways (a "real" unit can simply result in the same as having used the "fake" equivalent).