On 25/09/2019 08.54, Morten Sørvig wrote: > I see two differences between setting the DPI vs a factor: > > - You set one value per screen (DPI) instead of two (DPI & factor) > > - Qt can compute the factor, according to policy set by the application (as > mentioned above) > > [...] > > If possible, I’d like us to move away from relying on setting > environment variables, and/or switch to specifying per-screen DPI > instead of a scale factor. Has anyone considered whether or not this is *user* friendly?
As a user, I don't want to have to know/measure/compute the DPI of my display device. I just want to make "stuff" bigger or smaller. I *also* don't necessarily want the same physical size of "stuff" across devices. On my phone, I may want smaller "stuff", because my phone is usually quite close to my eyes. On my 4K 75" television, I may want larger "stuff" because I'm sitting 10' to 15' away. Maybe I have really good (or really bad) eyesight. Fiddling with "fake DPI" as a way of adjusting things has always felt like a hack. Setting display scaling "just makes sense". From a user perspective, it's obvious that scaling is also going to affect icons, style margins, frame thicknesses... basically, *everything*. DPI, historically, only affected font sizes and *maybe* some margins. If the only knob I have is DPI, how do I know (or control) what size my icons will be? How am I supposed to guess what will be the relation between "virtual" pixels and physical pixels, keeping in mind that I, as a user, am trying to achieve a particular value for that? There are a few instances, such as when representing physical objects, when it makes sense to try to achieve a particular physical size. In almost *every other case*, which is to say *always* for interface elements, there is no fixed correlation between "desirable" size and actual physical size, and anyone that designs their application otherwise is doing their users a disservice. -- Matthew _______________________________________________ Development mailing list Development@qt-project.org https://lists.qt-project.org/listinfo/development
