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enter image description hereenter image description hereOne of my main problems when it comes to drawing maps is how landmasses get distorted at different points. One of the continents in my story stretches almost to the north pole, but it looked very different when I projected it onto a globe; it was much thinner than I wanted it to be. Another one of my continents (located around the center of the world) appeared much wider on a globe. To people who draw maps, how do you account for distortion when going from a flat map to a globe?

Update: Using the advice I've been given, I've updated my map. It's not complete (as the red sketch lines show), but it does give me a better idea of where things are. Any criticism would be welcome.

Update 2: Included the finished version. I'll probably add more details to the landmasses eventually (the northernmost continent is much more detail than the others), but this serves just to give an idea of where everything is.

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    $\begingroup$ not to be picky, but worlds are on a globe, and the distortion happen when one projects them on a flat map $\endgroup$ – L.Dutch - Reinstate Monica Sep 25 at 18:26
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    $\begingroup$ Why not draw on the globe and project to a flat map? $\endgroup$ – Nuclear Wang Sep 25 at 18:26
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    $\begingroup$ You may want to spend some time becoming familiar to the look of Tissot indicatrices on various cartographic projections. You will soon get a feel of how shapes get transformed when going from a globe to a flat projection and back. $\endgroup$ – AlexP Sep 25 at 18:33
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    $\begingroup$ Many folks use multiple maps to minimize distortion in the area(s) that they care about. $\endgroup$ – user535733 Sep 25 at 18:38
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    $\begingroup$ @overlord I wish I'd known that earlier. $\endgroup$ – Richard Lindahl Sep 26 at 15:31
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I hope you like oranges

The first thing you need to do is peel an orange. Now lay the pieces out in order in a rectangle. Doesn't work? Of course it doesn't, a sphere doesn't map onto a rectangle without major distortion somewhere.

Now you could try drawing your maps onto an orange, but what you've really done here is generate an interrupted map projection. These are the projections with gaps to allow you to reduce the distortion of the land masses.

The goode homolosine projection is probably the best known of these. As you can see, distortion has been minimised, you can almost cut this out and wrap it back around a sphere. Goode_homolosine_projection

The greatest disadvantage of this particular projection from your point of view is that it's cut out around the landmasses of our particular planet, so just taking the outline directly isn't necessarily going to work for you. But the principle remains the same, start by drawing on an orange. Peel it very carefully so that you don't break up your continents or island chains, then lay it out flat.

As I said at the start, I hope you like oranges, you might be eating a lot of them by the time you're done.

The mandatory xkcd has a few more of the more interesting projections, including a couple of interrupted projections. Though something as simple as a sinusoidal or robinson projection may help with your distortion issue without getting overly complicated.

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  • $\begingroup$ Does this projection really minimize distortion? I just printed, cut and wrapped this map, and while the Americas, Europe, and Africa ended up forming something roughly spherelike, the part of paper with Asia on it looked more like an open clam shell than anything else. And this is not surprising at all if you look at the horribly distorted gridline in that part of the world. $\endgroup$ – Schmuddi Sep 26 at 13:27
  • $\begingroup$ @Schmuddi, yes, at the expense of all else, for navigation or measurement it's useless. That wonky gridline is a side effect of only having one interruption in the north but managing 3 in the south meaning that something has to give to allow for the large block of land that is Asia. The equivalent losses in the south are less pronounced. (I did say almost) $\endgroup$ – Separatrix Sep 26 at 14:16
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    $\begingroup$ The fuller projection is also useful, it minimizes distortion of land by just chopping up ocean. $\endgroup$ – John Sep 28 at 3:02
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I have dealt with this problem many times.

When it comes down to fixing a map you've already designed, while changing as little as possible, unfortunately you'll need to decide what is the most import aspects of the shape, scale, and distances of your world. To make it fit a sphere, it will need to be changed in some way.

Consider my original map: enter image description here

Pretty straightforward. Now look at what happens when I map it: enter image description here

As you can see, the distortion at the poles in unsightly. How do we fix this? It depends on what you're willing to do to your map.

For me, I shrunk the map vertically until the distortions disappeared. The following map adds 11% displacement above and below the land masses: enter image description here

And the following result: enter image description here

It already looks much better than before! You can even add a landmass at the pole if you want.

And you can take it even further: enter image description here

Which looks like this: enter image description here

You might be saying "but I don't want my world to be all ice or sea!" but look at this. The following image shows the same projection, but viewed from the side of the planet instead of viewed from the pole: enter image description here

As you can see, the ice is only just visible at the bottom and top of the image. Perspective is important!

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  • $\begingroup$ Unfortunately, manipulating your landmasses in this way makes your map less and less geologically sound. Why would a planet conveniently avoid having landmasses near the poles? $\endgroup$ – Arkenstein XII Sep 25 at 20:15
  • $\begingroup$ I have already added land near the poles for the reasons you have described $\endgroup$ – overlord - Reinstate Monica Sep 25 at 20:19
  • $\begingroup$ Adding landmass willy-nilly doesn't exactly make a map more geologically sound... but it is better than having blank poles. $\endgroup$ – Arkenstein XII Sep 25 at 20:22
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    $\begingroup$ The OP never said anything about making it geologically sound (despite "geology" being one of the tags), so I provided the easiest approach for correcting the distortion that I could think of from an entirely map-making perspective. $\endgroup$ – overlord - Reinstate Monica Sep 25 at 20:32
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    $\begingroup$ @ArkensteinXII one might ask why the Earth doesn't have any land mass at one of its poles... The answer might just be "that's the way it is" an given that this is a planet that we're constructing, that's just fine. Personally, I'd be more tempted to reduce the overall land mass, to have larger oceans, so the unevenness doesn't seem as glaring. $\endgroup$ – Baldrickk Sep 26 at 13:39
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You could do like GURPS and use an unfolded icosahedron ("d20") for planetary maps. Each triangle has very little distortion, and you can easily turn it into an icosahedral globus. Here is a map of the Earth done this way:

enter image description here

For regional maps, you can put any two adjacent triangles together as a rhombus (diamond) shape.

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    $\begingroup$ Worth noting that the reason for choosing an icosahedron is that it has the most sides of all the regular polyhedra (where all the sides and angles are identical). Also, once you've projected the globe onto the triangular faces, you're free to cut the individual triangles into pieces and attach some pieces to adjoining triangles in order to minimize the splitting of continents, as in the dymaxion map. $\endgroup$ – Hypnosifl Sep 26 at 14:35
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Free software like Blender lets you easily draw onto a sphere, and then unwrap to an equirectangular projected map.

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Dispense with realism.

roman map

https://earlychurchhistory.org/politics/the-roman-empire-china/

Depicted is a round map of the world, supposedly as the Romans knew it. This map has been much copied; I struggled but could not find where this image originally came from. If someone can find it please post link.

In any case - you can make a fine map and not get undies in a bundle over precise topography. You could definitely use this map to figure place relationships in the mediterranean.

Another good map would be one drawn by a character in your story - with familiar places and points of interest labelled prominently and drawn large and central, and further abroad landmarks and foreign cities more or less guessed. I like the idea of a map credited to a secondary character - perhaps a scholar encountered on the way.

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  • $\begingroup$ Looks like it might be derived from Hecateaus's Map. $\endgroup$ – Arkenstein XII Sep 25 at 22:15
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    $\begingroup$ Aha! It is in fact a reconstruction of Pomponius Mela's Orbis Habitabilis. $\endgroup$ – Arkenstein XII Sep 25 at 22:22
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    $\begingroup$ @ArkensteinXII - excellent! Thank you. $\endgroup$ – Willk Sep 25 at 22:51
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    $\begingroup$ Yeah, for most of our history, how things are connected was more important than how they're laid out in 3D space. This sometimes lead to routes that were longer than necessary, but when you rely on horse-drawn carts and sailing ships, the most direct route isn't usually the best route anyway. Heck, even today, intercontinental flights rely on wind patterns to save time and fuel whenever possible. $\endgroup$ – Luaan Sep 26 at 11:36
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    $\begingroup$ Rotate right 90 degrees. It starts looking a LOT more familiar, if not particularly accurate, places are in roughly the right places relative to each other - bearing in mind that it is just a snapshot of the areas around the Mediterranean. The shape is more down to the limited reach across the world restricting their knowledge of what lies beyond. $\endgroup$ – Baldrickk Sep 26 at 13:40
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I think you need to decide what you want this map for. If it's meant to help you with worldbuilding, it's more important to get the projection right. If it's meant to be used in-universe, like if a character in your story made it, it actually might make more sense to have it not to scale at all.

Historically speaking, maps that look like a bird's eye view have been rare until the invention of aircraft. They're hard to make, and not that useful; people don't naturally navigate by latitude and longitude coordinates. Most pre-modern maps that people actually used in their day-to-day lives looked more like a bus route graph than a map. They would have been a tree, with landmarks marking the turns. "To get to Byzantium, follow the north road past Antioch to Tarsus, then follow the west road..." Here's an example of what I mean. This is a 13th century copy of a 4th century map of the Roman Empire.

To be honest, that's still how most of us navigate usually.

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The quality of a map depends on the society that creates it.

If your world is swords and sorcery, then ignore "reality" and stick with maps that represent what the society knows and believes.

If your world is early tech, then a mix of both "reality" and "classic" maps might make sense.

If you world is spaceships and sky stations, then go with a globe.

You might go with a variation of things. For instance, the world is actually flat, but some space flight is possible. Maybe space flight is not possible because people keep running into the dome of the sky.

You could also go with a variation of map projection. For instance, draw the map on a globe then draw the land map the same on a flat map but accept that the oceans will be over stated.

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Adding a new answer in order to respond to your new image.

This one is much better!

Personally, I think you should always work with an image with an aspect ratio of 2:1. This is a special kind of projection called the plate carrée projection, and this kind of projection has no distortion at all near the equator.

During my original calculations, I thought that an image with an aspect ratio of 3.14:1 (or pi to 1) would be what I needed, since the circumference is pi times the diameter:


enter image description here


But I was wrong. Below is the result of an aspect ratio of 3.14 to 1: enter image description here

And so I was scratching my head. So I looked at some Earth maps I had downloaded and saw that their aspect ratio was 2:1.

So then I tried an aspect ratio of 2:1, as show below:


enter image description here


And it was a success! enter image description here

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