• IrateAnteater@sh.itjust.works
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    6 days ago

    Because a flat surface is an x-y plane. The ground is a “flat” surface, and so the z dimension is height.

    For me, that’s the only way that makes sense. But I program robots for a living, so I’m used to dealing with coordinate systems where the flat reference is the ground. Programmers seem to be using the screen as the flat reference. If I were building a game world, I’d probably use z-up convention.

    • theunknownmuncher@lemmy.world
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      6 days ago

      Programmers seem to be using the screen as the flat reference.

      In screen coordinates, the origin is the top left corner of the screen, and the Y-axis increases towards the bottom of the screen. So Y still isn’t “up”

      • Redex@lemmy.world
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        5 days ago

        His point is that’s where it comes from. In most 3D software as seen in the chart, the XY plane is paralel to the screen, just that Y is up instead of down like in 2D, cut that would be insane if it was like that.

    • popcar2@programming.dev
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      6 days ago

      Yeah, it depends on whether you expect the 2D view to be on the floor or on the wall. If it’s on the floor, Z is up. If it’s on the wall, Z is forwards & backwards (depth). Personally I think it being on the wall makes way more sense since we already expect from 2D view that Y is up and down, it feels weird to shift it to forwards & backwards when switching to 3D.