[samirm]

Thanks for the trivia, although your comment on displays is a bit misleading: >I first viewed it on a Linux desktop; on a Mac laptop with Retina display it looks much better though somewhat “light”

There's nothing special about Apple displays that makes them "retina", it's just a (marketing) term they use that denotes a standard for pixel density at a specific distance away from the screen. The point I'm trying to make here is you could have just as easily had a "retina" display on your linux machine, if not better.

[svat]

Yes you're right that Linux or Mac is irrelevant (and I should have omitted mentioning the OSes); my point was just that on a typical desktop monitor (28-inch monitor at 2560x1440, so about 105 dpi) and at typical zoom level, the effects of rasterization are very much apparent (and still would be on a so-called “4k” monitor), while on a typical reasonably-good laptop display (221 dpi), it's only slightly better. Basically, computer screens have still much lower resolution than a typical office printer (600 dpi), let alone the high-resolution typesetters (5000+ dpi! https://news.ycombinator.com/item?id=20009875) that TeX/METAFONT were designed for.

One sometimes hears that screens are now high-resolution enough that the usual tricks done for font rendering (http://rastertragedy.com/) — anti-aliasing, sub-pixel rendering, etc — are no longer needed, but in fact we still have a long way to go (if we'll ever get there) and these PDFs that use bitmap fonts serve as a good test case.