• yopyop@feddit.de
    1·
    1 year ago

    I work in 3D metrology and the consensus is right handed and Z up. Had no idea left handed existed!

    • heeplr@feddit.de
      2·
      1 year ago

      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?

      • Pelicanen@sopuli.xyz
        11·
        1 year ago

        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.

        • heeplr@feddit.de
          1·
          1 year ago

          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.

      • yopyop@feddit.de
        0·
        1 year ago

        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.

        • heeplr@feddit.de
          1·
          1 year ago

          Sorry for being unclear, I was talking about screen projection. For actual rasterization.