How to detect sub-pixel movements?

Hi, I’m trying to detect mouse mickeys for movements when the mouse hasn’t
yet moved a whole pixel. As far as I can tell, motion.relx and motion.rely
return mickeys of relative motion, but they do not change unless motion.x or
motion.y has changed, which is per pixel, and that’s not what I want. Is
there any way to to it? Thanks.

I think it’s impossible with SDL. You want to make use of mouse real
resolution instead of being limited to screen resolution, right?

I see one thing you can easily do to make this effect:
Slow the mouse down!
In example, when mouse has moved a pixel, you consider this a movement of
1/4 of pixel and warp the mouse using SDL_WarpMouse to the position you
want. One issue: the app user will need to speed up a mouse in his system
It’s not DETECTING sub-pixel movement, but HEY, it’s working :).