It gets more cursed the more you look at it:
- you have to convert the coordinate axes (swap z,x,y)
- then you find out the right/left handed is flipped
- now your brain melts if you even try think how to solve this with transformation/rotation, what ever.
I found this handy reference a while ago. But yeah, we are kinda screwed.
At least they haven’t invented X up (yet)
You’ll never believe my startup idea
I work in 3D metrology and the consensus is right handed and Z up. Had no idea left handed existed!
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?
I thought right-hand rule with Z up as thumb was standard in science? You usually project on the xy-plane, for example when calculating the distance to objects on a flat surface.
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.
TBH I’m not sure I totally understand the question but projection is very useful to decompose the orientation of elements, like a cylinder that you just measured with a machine or a scanner. The coordinates and orientation (angles) can be projected in the three main planes XY, YZ and ZX.
Sorry for being unclear, I was talking about screen projection. For actual rasterization.