• boojumliussnark@lemmy.world
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    3 days ago

    I don’t quite get this. The human head, like the globe, is not flat. Shouldn’t that be reflected in the projections? When projecting the earth in Mercator, we see the whole earth, not simply a “profile” of earth. I would expect a projection of a head to include the whole surface of the head, not a simple profile. How is this actually factual?

    • mozingo@lemmy.world
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      3 days ago

      This isn’t representing projections of a human head. This is representing projections of the globe if the globe had a giant human head drawn on it instead of the continents.

      • pruwyben@discuss.tchncs.de
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        3 days ago

        But then you have to figure out how to transfer the drawing of the head onto the curved surface, and how you do that is going to determine how the projections look.

        • FooBarrington@lemmy.world
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          3 days ago

          No, you can ignore that part. The image isn’t showing how to accurately draw a head onto a surface, it’s showing how this given head drawing would look in different projections.

          • pruwyben@discuss.tchncs.de
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            2 days ago

            Projections from what? You don’t need a projection for a drawing, it’s already a 2d image.

            Edit: I realize that you can use it to compare the different projections to each other, but it doesn’t show which one is more accurate overall. In this image it looks like they used the globular projection as the "default’ with the most realistic drawing, and created the others based on that, but they could have picked any one of them to be the default.

            • FooBarrington@lemmy.world
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              2 days ago

              Yes, again, that’s the point.

              It assumes the sphere projection is correct, and shows how each of the 2D projections isn’t correct. This isn’t hard.

    • Flying Squid@lemmy.worldOP
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      3 days ago

      It’s still a Mercator projection if you take a world map done in that way and cut it in vertically in half, isn’t it?