Apple's HiDPI is "2x scaled" on Retina and >= 4k displays. But you can still pick a virtual resolution that isn't exactly 0.5x your display's native resolution, and it will look great.
For example my external monitor is 3840x2160, and has a default virtual resolution of "1920x1080", but I run it at "2304x1296". My 14" MBP display has a default virtual resolution of "1512x982", but I run it at "1352x878". Neither looks scaled, neither has a slow display, weird fonts or weird graphics. I never even really think about it. In other words, light years beyond the experience on Ubuntu and on Windows.
You omitted the next word in your quote, where I mentioned what Apple does—downsampling.
Your displays are high enough resolution that you may not notice the compromises being made, especially if you don’t get an opportunity to compare it with real fractional rendering, but the compromises are real, and pretty bad at lower resolutions. Pixel-perfect lines are unattainable to you, and that matters a lot in some things. And you might be shocked at how much crisper and better old, subpixel-enabled text rendering is on that same display.
Apple was in the position to do it right, better than anyone else. They decided deliberately to do it badly; they bet big on taking typical resolutions high enough that downsampling isn’t normally needed (though they shipped hardware that always needed such downsampling for some years!), and isn’t so painful when it is needed; and they’ve largely got away with it. I still disagree with them.
As for 1352×878, what on earth is that number, for a native 3024×1964 panel!? 2.237. It’s like they’re gloating about not caring about bad numbers and how terribly inconsistent they’re going to make single-pixel lines.
> Your displays are high enough resolution that you may not notice the compromises being made, especially if you don’t get an opportunity to compare it with real fractional rendering, but the compromises are real, and pretty bad at lower resolutions. Pixel-perfect lines are unattainable to you, and that matters a lot in some things. And you might be shocked at how much crisper and better old, subpixel-enabled text rendering is on that same display.
Do you have a test case where I can see this in action?
Nothing handy, sorry. For comparable results, you’d need to use an old version of Mac OS X. Up to 10.13, I think, if you can ensure subpixel text rendering is active.
Sorry, what I mean is, is there an image or PDF I can bring up that will show me imperfect lines on these displays?
As for rendering of text, there is definitely antialiasing in play. Subpixel rendering is no longer used, but I don't think you need it at these resolutions anyway. I'm not even sure what the subpixel arrangement is of my display (is it neat columns of R -> G -> B, or larger R and B with smaller but more numerous G? At 250-some PPI, the pixels are too small to notice or care!). But, I agree that if I was using my old 1920x1200 monitor I would miss it.
Apple's HiDPI is "2x scaled" on Retina and >= 4k displays. But you can still pick a virtual resolution that isn't exactly 0.5x your display's native resolution, and it will look great.
For example my external monitor is 3840x2160, and has a default virtual resolution of "1920x1080", but I run it at "2304x1296". My 14" MBP display has a default virtual resolution of "1512x982", but I run it at "1352x878". Neither looks scaled, neither has a slow display, weird fonts or weird graphics. I never even really think about it. In other words, light years beyond the experience on Ubuntu and on Windows.