I wondered for a long time how it would be handled when screen pixel densities got high enough. There are a couple ways to handle it, and apple took the only on

I wondered for a long time how it would be handled when screen pixel densities got high enough. There are a couple ways to handle it, and apple took the only one that seems completely backwards compatible: they abstracted the notion of "1px". I guess it couldn't have really evolved any other way, but damn that is messy.