This is discussion archived from a time before the current discussion method was installed.
Morgan Wick: Seen in almost any video game that uses a world map wgere tge okater cab freely travel. ?!?
Shire Nomad: "where the ?????? can"? I'll correct what I can comprehend.
Andyroid: "where the player can". I think Willy Four Eyes had his hands in the wrong place on the keyboard while trying to touch-type. It's happened to me before.
Morgan Wick: This is why they tell you to read what you write before sending it in.
Dikiyoba noticed we had Civilization as an example twice, and so combined them.
Pro-Mole: Huh... I'm not a mathematician(or even geometrist, if that exists), but... if you travel always to the West in Earth, say, from New York, wouldn't you eventually get back to New York again, even though Earth is roughly a sphere? Also, if the world map loops in the X and Y as well, isn't it easy to define it as a sphere(and thus loops in any direction) rather than some weird "hypertorus" that's composed of two perpendicular thorus? Also, anyone got my point after all that imaginary geometry?
Rissa: After spending hours trying to teach a friend of mine how to draw a world map (she's a world-building author, I'm a mathematician, she insisted on breaking the titular law) I know precisely what you are on about. The problem is that the loops you encounter in these games don't work the way they would on a sphere. If you go off the bottom of the rectangular world map, let's say fairly near the left edge, you reappear at the top edge, fairly near the left. This implies that those edges are connected all the way along (imagine rolling up a map) and so you have a tube. And given that it loops horizontally too, this tube is then connected to itself to form a ring donut. It's the only shape that makes sense.
Oh, and geometrists do exist, but they prefer "geometers". Be nice to them, or they'll knot you.
Madrugada: Thank you for that explanation, Rissa. I was just going to ask the same question. But doesn't the toroid thing assume that anyone making a loop around a sphere is going to be making a Great Circle? I mean, if I travel straight west from Toledo, Ohio to Omaha, Nebraska and then continue on around on the same line, I'll come back to Toledo but I won't do a Great Circle. I'll basically follow the latitude line at 52 N (roughly). Or is that simply an artifact of the fact that most fictional maps are flat projections?
Rissa: The thing that causes the toroid problem is that all the loops are the same length. Travelling along the very top of the map, the equivalent on a sphere of just running round and round the North Pole, takes as long as travelling along the equator (and is the same distance).
