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OSX does not support fractional HiDPI scaling, but nobody made a fuss, ever. So I wonder, why is that a bad thing, when Linux doesn't do it either?
by vetinari 10y ago
OSX does not support fractional HiDPI scaling, but nobody made a fuss, ever. So I wonder, why is that a bad thing, when Linux doesn't do it either?
- MBCook 10y agoI believe it has ever since going Retina. It wasn't always presented up front, but it was an options.
- izacus 10y agoIt's even default on the new 2016 pros.
- vetinari 10y agoIt's still integer only scaling. OSX uses slightly different trick - it creates a framebuffer that is @2 scale and lets the hardware to scale it down. (iOS goes even further and has @3 scaling). Which is the right approach - for example, one of the rMBP options is to have 1440x900 (2880x1800) resolution, which to the native 2560x1600 is the ratio 9/8. Nobody is going to track that 9-th pixel for each block of 8 pixels in software. Using hw scaler is simpler, cheaper and has smaller margin for errors. Frankly, implementing fractional scaling is waste of time, resources and would produce software that is slow, buggy and bloated.
- rcthompson 10y agoI'm aware of how OSX implements scaling. It's still rendering at a resolution that is a non-integer multiple of the screen's native resolution and then scaling it to the native resolution. How is this not fractional scaling?
- vetinari 10y agoUser space software stack is not aware of it, the frameworks know only of scale 1, 2 and 3 (on iOS). Nothing between it. That's why it is integer scaling. The fact that the framebuffer size is not the same as display resolution is known only to the driver and it is not something that is requested to be implemented for Linux.
- some_guy_there 10y ago> User space software stack is not aware of it, the frameworks know only of scale 1, 2 and 3 (on iOS). Nothing between it. That's why it is integer scaling. Well whatever the case might be, whether it's kernel's fault, GNOME's fault, Wayland's fault or device driver fault, fact of matter is that one can easily get 1920x1200 resolution on Retina Macbook 15" with sharp font and images, and cannot on Fedora. This is why perhaps people are making "a fuss". OS X CAN do fractional scaling as far as user is concerned (doesn't matter who scales it up or down), while Fedora cannot (with Wayland, at least).
- coldtea 10y ago>User space software stack is not aware of it, the frameworks know only of scale 1, 2 and 3 (on iOS). Nothing between it. That's why it is integer scaling. It doesn't matter whether they know it or not, since they work transparently great with the scaling factor. In fact it's even better than having the software stack aware of it (simpler, less room for errors). The end result is that fractional scaling resolutions works on OS X and not on Wayland (from what I read, haven't checked Wayland myself recently).
- MBCook 10y agoOh, that's right. I'd forgotten about that. Thanks.
- coldtea 10y agoWhatever the mechanism, it does have it and it IS fractional scaling on non-integral multiple of the screen DPI.
- xyzzy_plugh 10y agoBecause these are all regressions.
- AsyncAwait 10y agoIt is an entirely new compositor, after 30+ years of X, so there will be things to work out yes, but the fact that Wayland is finally here is huge.
- rcthompson 10y ago> OSX does not support fractional HiDPI scaling Yes it does. It's right there in the system preferences.
- vetinari 10y agoNo, it does not. See my reply below.
- coldtea 10y agoOS X does. So the rest of the question is moot.