I understand that the mapping of input and output pixels might cause a shift. However, if I start out with 'none', then go to 'hq2x' and then go back to 'none' then I would expect to have the same image alignment which I started with. However, this is not the case. I need to go back and forth between 'none' and 'hq2x' several times in order to get back to the correct starting alignment.
Just try Super Mario Bros 1 @ 4,5x (vert scale) (1080p) and look at the bottom of the screen. Then go back and forth between 'none' and 'hq2x'. You can see that the bottom of the two bricks are sometimes cut off, and sometimes it's not. If you are still unable to reproduce this I can make a video of it.
I don't think I have seen it change between different positions. you mean if you change between one and hqx, it will be in different positions each time? or you mean changing the width doesn't seem to change behavior? I'm sorta confused. I need to be able to reproduce this so I can fix 'er.
I can confirm that it does this too. It doesn't require 4.5x height (I just did it with a 5x height) and it does it for all the scalers (hq3x, hq4x, etc).
Just switch between hq3x, none, hq3x, none, hq3x, none, etc
or hq4x, none, hq4x, none, hq4x, none, etc
And as you're doing that watch how the image sometimes sometimes shifts left, sometimes right, sometimes not at all. Kinda odd, but I don't use scalers so never really noticed it before.
Edited by cacophony, Sun Mar 12, 2017 4:04 PM.