by Penguinator » Mon Sep 23, 2013 5:10 pm
Depends on the monitor. If it scales without cropping then things will look slightly fatter in portrait mode (and slimmer in landscape), but if it crops (ie. adds black borders to correct the ratio) then it should look correct (ie. ball isn't elliptic).
My Samsung monitor (16:10, 1920x1200, 24") can display 16:9 (and other common ratios like 4:3 and 5:4) by cropping. It also scales to nearest neighbour (instead of having bilinear filtering), so it's even suitable for old games with small resolutions (eg. from 320x240 to 1280x1024).