2-1, 2-2, etc and then 3-1, 3-2 etc going in a clockwise direction from 1-1. I've suddenly got the urge to play this again as well, damn thread revival :/
All engines should support it. The UV sampling goes from 0-1 in both U and V directions You simply lay it out on a 2:1 space, like from -1 - +1 U and 0-1V then scale all the UV's by half (0.5) on the U axis and put them back into the default 0-1 UV space. IN your program they'll look stretched but they will read a 2:1…
I was watching a video from Flippednormals and they were going over midpoints for displacement maps. I was always told before when using 16bit tiff to use 0.5 as the midpoint and when using a 32bit exr to use 0 as the midpoint, but that video was talking about values like -1 and even 1 if python was involved. I have zero…