I only know thumb = motion/current but now since you say, it’s clear: people used x/y for 2D logically but the 2D plane used to be paper. which is parallel to the earth surface (usually). Computer screens are perpendicular so Y points up, not away from you.
So this makes sense with paper, TIL. With computers, Z traditionally means depth.
How does projection work in your field? X, Y, Z get converted to X, Z and 2D screen planars have no Y axis?
Who invented this, why did she do it and where to send my official letter of complaint?
you’ll get bitten during projection when depth is converted to 2D screen coordinates, which is X and Y. Better do it right from the start.
In which world should Z point up and Y represent depth?
Totally crazy opposite world, where cats hunt dogs and rain goes up? This is plain evil…! :-)
Sorry for being unclear, I was talking about screen projection. For actual visualization.