Hi @senthor that's not how PPI works... vector scaling doesn't affect anything but size. Example:
100% = A 200% = A
It doesn't matter where you watching this or the screen resolution you have on your computer - mobile phone right now, both "A" has the same quality and PPI. But one is (x2) the size of the other.
rMBP15 native resolution is 2880x1800 and therefore it is a 220 PPI panel. If you do the 1440x900 (x2) thing you just do a 200% vector zoom, everything with the double size but keeping all the quality from native resolution. (Bitmap zoom works different).
100% = A 200% = A
It doesn't matter where you watching this or the screen resolution you have on your computer - mobile phone right now, both "A" has the same quality and PPI. But one is (x2) the size of the other.
rMBP15 native resolution is 2880x1800 and therefore it is a 220 PPI panel. If you do the 1440x900 (x2) thing you just do a 200% vector zoom, everything with the double size but keeping all the quality from native resolution. (Bitmap zoom works different).