> On 2 Mar 2016, at 09:37, Welbourne Edward <[email protected]> > wrote: > > Andreas Hartmetz said: >> Arcminutes are a really good idea. The size of screen elements isn't >> really about physical dimensions, it's about size on retina (the >> actual biological thing ;) really, or legibility. > [...] >> If the system had "known" that the typical user to screen distance was >> 2-3 meters and acted accordingly, that wouldn't have happened. Of >> course, you need to know the "typical viewing distance" for a screen, > > So perhaps what we should be using to configure UI scaling isn't a scale > factor but this typical viewing distance; as long as the system has some > way to discover the physical dimensions of the screen and its pixels, it > then know everything it needs to scale the UI sensibly.
But some devices tell lies in their EDID data, and some don’t. And with a projector you don’t know the physical size either. So we can’t always discover the physical dimensions without user intervention. (At least xorg.conf provides a way to override it.) We could have some kind of calibration tool to help close the loop: a wizard that detects all possible settings, tries some tweaks, asks you to measure some calibration rects and text (rendered with both QtQuick and widgets) with a ruler, and then suggests settings that you probably need to adjust manually. Kindof like using a colorimeter to calibrate color. Except other software and hardware would keep changing out of our control, so this tool would never be “done”. And really the desktop environment should have a sufficiently powerful control panel that we don’t need to write that. But maybe it’s worth a try anyhow. _______________________________________________ Development mailing list [email protected] http://lists.qt-project.org/mailman/listinfo/development
