Suggestions on Building and Distributing a Large Scale Map

[nemesis702]

Over the past three months, I have been really crunching down on creating a campaign map for a world I've spent a few years conceiving. After some consideration, I settled on a world size of roughly 22,000 miles around the equator and circling the poles. I understand that the axis poles should be cold and icy, and regions closer to the equator warmer. Plants and animals tend to be similar on lines of latitude equidistant from the equator.

Simple enough.

What I need help with is some other general things that tend to be universal on Earth. Also, given the size of the map in question, how might I go about presenting it in a digestible format to my players?

1. What size image should I make it on GIMP as far as scaling in order to make reasonable details like major roads, villages, etc. (pixels/mile)?

2. Should I use projection techniques?

3. Should I perhaps just make multiple maps of each continent so detail can be preserved?

4. Three dimensional model?

5. How far up the creek am I with these options?

Any ideas on how to present this are greatly appreciated. Thank you.

[ScotlandTom]

I recently started work on mapping my campaign world as well. I got a lot of help and inspiration for creating a believable map from this thread here. The creation process for the map in that thread covers everything from ocean currents to humidity to tectonic forces and overall it's pretty simple to follow. That should give you a good starting point for your geography and climate.

How to present your map without overloading your players? Well, I would prefer my players asking "what's over that mountain?" and not "what's on that other continent?" In which case I would suggest keeping your overall world map to yourself for reference and simply create smaller regional maps that fulfill your player's immediate needs. Such maps could be easily printed on standard paper in whatever printer you have available. This is the route I'm going. I've created my world map at a large enough resolution to be printed as a poster sometime in the future (24"x36" @ 300dpi). At that size I've wound up with an image 10,800 pixels wide, which would equate to just over 2 miles per pixel around the equator in your case. If you're curious, a completely blank Photoshop document with those dimensions is 222.5Mb. I recently completed work on the overall world map which gives me basic info on climate and terrain, but isn't at all useful for distances considering the curvature of the planet. I will probably create continental maps (still not useful for distance save for small continents) which will give me more terrain details and probably political maps. Then I'll move on to regional maps that will actually be useful for distances and will likely be more useful to my players as well.

1. For your world map I don't think you need anything larger than about 2 pixels per mile. Unless the map is actually printed on a globe, scale is actually pretty meaningless here. Just go with a nice rectangle (again, 300dpi 2:3 poster size works well and can be made into some nice wall art later). I would consider only marking truly major cities, roads and landmarks on this scale. Again, this will mostly be for reference as the scale of the map won't be very useful to you.

2. Having never used such techniques myself I can't really advise you either way on this.

3. Yes, make multiple maps. A world map is good for your own reference, as are more detailed continental maps. Continental maps could come in useful for players and definitely make regional maps for your players to use.

4. Could help for making more accurate maps at smaller scales. In Photoshop I took my world map and created a 3D sphere layer using an image of the map. It really showed me what mistakes I'd made in the map creation process and allowed me to see exactly how everything came together at the poles. Very very useful for a map-creation reference. I don't know if GIMP has an equivalent feature, but I would recommend putting your map on a sphere early in the creation process to ensure everything lines up and that you understand how your world fits together.

5. I don't think you're far up a creek at all considering you're still in the planning phases. Even if you are far up there you most certainly have a paddle or two.

Hopefully all that helps. I fear I repeated myself a few times, but those are my thoughts for you.

[Schwarzkreuz]

On my Arden Campaign map I used the "known" World of the empire, from which most playercharacters and the most sophisticated cartographers of my world come from, It have roughly the size of Scandinavia to Northafrica for scale. Dont overdo your details exept it is a merchant trading/ Pirate / Wiking kind of map than concentrate on important capitols and coast cities and ports, try to imagine what the natural, cultural and travelable borders of the area your group inhabit. If it is a world tournee and they visit another continent every day you play... well, lots of maps to do.

[Hai-Etlik]

Sorry, this post ended up being a bit longwinded and it may get a bit confusing. I hope it helps though.

In geography/cartography jargon "large scale" means "things are drawn large" not "large area covered". A map of a whole planet is has a large "extent", but in order to fit into any kind of reasonable sized map, it needs a very small scale. Also, the ecology is not consistent at a particular latitude, oceans and their currents can affect temperatures, and ecology is at least as much influenced by moisture as by temperature: Bangladesh is at the same latitude as the Sahara.

Projections aren't something to be used or not used in isolation from the rest of the process. They are the ways of dealing with the fact that the world is a sphere, and a map is flat. Your options are to make the world flat (or a cylinder or cone), use a projection to flatten it (and distort distance in the process), or make a map where distance on the map is not representative of anything in reality. So if you want a round world, you want distances to be meaningful (It's distorted, but the distortion is known), and you want to cover any significant portion of the globe, you have to pay at least some attention to the world being round, and that means considering projection.

Maps of smaller extents should be in different projections from a global map. Any projection will distort things significantly somewhere on the map. On a global map, something is going to be stretched, squashed, or inflated. Zooming in on it is STILL going to be distorted. By using the right projection for an extent, you can minimize the distortion over that extent. You can sort of get away with just "zooming in" if you use a conformal projection, particularly Normal Mercator (Which is why web maps like Google Maps and OpenStreetMap use it). It's a passable projection for a global map (it's the traditional wall map projection) and if you zoom in a lot, it's very close to what a proper projection for that extent would show, but in the middle, for extents like whole continents, it looks off. It also massively distorts the sizes of features: It shows Greenland as being the size of Africa for instance. Any other projection that's any use for a full globe will produce horrible results for most smaller extents

If you want to do this properly, I'd recommend developing a base map with minimal styling to be reprojected as needed. A vector GIS format would be best, but you would have to use GIS tools for that. That's more tools to learn, but you'd be using the tools specifically designed for the job. You could project the base map as needed far a particular map, then style and add details. This is roughly how real world maps are made. A GIS is a complex tool with a LOT of capabilities, though you'd only need to learn how to draw in and edit vector features ("digitizing") and convert between projections. Failing that, a very simple map with flat colours can be run through a tool like G.Projector and then be styled.

As a rough analogy, if you know how to use a circular saw and need to cut a curve, you can rough it out and then file and sand it down to a curve with a lot of work (Do it right with just graphics tools), or you can learn to use a bandsaw and then just cut the curve directly (Use GIS tools), or you can approximate a convex curve with several straight cuts and hope you don't need any concave curves (Fake it with Graphics tools).

They are all valid options. If you just want a rough, not to scale map works, draw one, it worked for what few maps were drawn in the middle ages. If a picture that looks like a proper map to you, works for you, fine. If that's all you need, go with it. (Though I admit I cringe at global maps in platee carre with no polar distortion and both compass roses and scale bars) If you want a real map that works, you either have to learn what that means, and then either do a fair bit of work using just graphics tools, or learn the tools built for doing this. This doesn't remotely require going out and getting a degree in geography or diploma in GIS, but it does require learning the basics, and doing more work and thought than just drawing things.

[nemesis702]

After a long period of editing on the wiki, I'm back to review the suggestions and comments so far.

I got a lot of help and inspiration for creating a believable map from this thread here.

Thank you for the quick reference. The scaling suggestions are very useful. It is nice also so get some definitive suggestions based on personal experience.

On my Arden Campaign map I used the "known" World of the empire... concentrate on important capitols and coast cities and ports, try to imagine what the natural, cultural and travelable borders of the area your group inhabit.

Well, I would prefer my players asking "what's over that mountain?" and not "what's on that other continent?"

I had been considering giving out map information in this method previously. It is a good idea for the purpose of giving a PC perspective, but half of my problem has been giving the players, not the characters, the reference they would like. The world is fairly well mapped out in game. Magic isn't really something we had as an advantage IRL. I am obscuring some information as well though. This is a good idea for in game, less metropolitan cities though.

In geography/cartography jargon "large scale" means "things are drawn large" not "large area covered". A map of a whole planet is has a large "extent", but in order to fit into any kind of reasonable sized map, it needs a very small scale. Also, the ecology is not consistent at a particular latitude, oceans and their currents can affect temperatures, and ecology is at least as much influenced by moisture as by temperature: Bangladesh is at the same latitude as the Sahara.

Any suggestion for a fair mix of both scale and extent then? It does not need to be the whole map, but I would like at least a transcontinental concept. The comment on ecology has more to do with the progression and migration of people. For a quick example, the Mesopotamian cultures found it very easy to grow crops that were native to their area in Europe due to a supportable climate there. This was much more difficult for certain crops during the colonization of sub Saharan during imperialism.

...in a global map, something is going to be stretched, squashed, or inflated.

How large do you feel a map can be to minimize this effect so that the change is roughly 10% or so? (arbitrary number)

If you want to do this properly, I'd recommend developing a base map with minimal styling to be reprojected as needed. A vector GIS format would be best, but you would have to use GIS tools for that. That's more tools to learn, but you'd be using the tools specifically designed for the job. You could project the base map as needed far a particular map, then style and add details. This is roughly how real world maps are made.

Could you link to any pages explaining this more in depth? Are there any free/cheaper GIS programs you have tried?

Thanks to all contributors so far. I'll continue to check for updates every few days.