Hello, this is not a programming question but something I've been asking myself.
The new "direct to display" feature is supposed to present a full screen Metal game without intervention of the window server. Although it looks nice on paper, I'm worried about how scaling will be performed, if it’s not done by the window server.
Currently, on retina Macs, a game that runs at exactly half the monitor resolution (e.g., 1440*2560 on a 5K iMac for instance) will look very sharp because the window server is clever enough to perform integer scaling, simply quadrupling the pixels. There is no pixel interpolation that typically blurs the image on an LCD that is not set to its native resolution. One pixel in the game is exactly 4 pixels on the monitor, and this is great.
But if scaling is not done by the window sever, I suppose it will be done by the monitor hardware, which always performs pixel interpolation even when not needed. PC gamers have been complaining about it for years (a 1080p game on a 4K monitor looks way worse than on a 1080p monitor).
I'd like someone to enlighten me on how scaling will be performed with “direct to display” and I want Apple to know about this possible issue. Currently, games on a 5K iMac look very nice at 1440p (most won’t run at 5K). I don’t want them to look blurry with Metal 2.
