What is the interaction with zooming? You can't just deny zooming. Users want it, and if you disable it, someone will still monkey-patch it in. A first-order s

What is the interaction with zooming? You can't just deny zooming. Users want it, and if you disable it, someone will still monkey-patch it in. A first-order solution is to have 'zooming' be pure scaling. Essentially, instead of ISO defining a milimetre, the user defines it, and it defaults to the ISO definition. This essentially means the system has to handle a screen-size that could change at any given time. Unless you are willing to accept interpolation. But then, what happens when real-distance starts to matter. A stupid example is a ruler app, that obviously breaks upon scaling. Generally, any app that depends on `real hardware' interacting with the screen, this is going to be an issue. Specifically, this is an issue for touch screens. Even more so because 'human hands' are `real hardware'. If two buttons are rendered 2cm apart, and the user scales by a factor of 2x, that would put the buttons 4cm apart. That might be too much of a spread to use comfortably. In general, does it really make sense to treat a 14" screen scaled at 2x as a 7" screen? What about a 15" screen scaled at 3x? If you accept the above as a problem, there are many solutions, but they are either a lot of work, or require 'monkey patching'. Sadly, this means the quote "Resolution independent graphics is a solved problem." not quite right. At least insofar as any chosen system will have trade-offs between ease of development and ease of use. Taking a pessimistic view: Those trade-offs will inevitably fall towards development on occasion, which will train users to think this is stupid anyway. Thus developers get less benefit, and we will see weird monkey patching to attempt to fix this. Maybe at some point, someone walks in and declares "this is a mess, it should have been done right from the start".