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how do you chart space in your sci-fi games?


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I've been very interested in doing a sandbox solitaire (1 player) game of exploring unknown space.

I'm using MG Traveller v2 and GURPS Space to fill in more details.
MGT2 has the hex maps and uses the rimward, coreward, spinward and trailing which confuses me. If you think of planets spinning around a star/sun you can think of grooves on a vinyl record yes? If so the confusing part then spinward and trailing gets reversed depending on your viewpoint. If I'm looking down on the record it spins clockwise but if I were to look "up" at from "below" it would then be counter-clockwise.

the hex maps are fine in that they give you a flat reference but how do I know where something is actually at in a 3d space in each hex?

Or am I making to much of this in that travel would be: punch in planet or waypoint and hit go, much like a gps in an aircraft?

I guess what I'm looking for is a more detailed representation of space itself and the more I get into it the more mind-boggling it gets.

Anonymous GM

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Mindjammer does it with three dimensional cubes nested within each other representing space sectors, which is more true to life but also seems practically impossible to actually use at a table. The hex mapping thing is much less realistic, but seems like it's a necessary concession to actually being able to manage it without needing to build software to do it.


Silent Spirits
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I wouldn't worry about try to make it more detailed and physically realistic to be honest. I personally think it's more useful in game terms to detail a network with the different lines between the stars representing travel times since I think most of what players want to know revolves around "how long does it take to get here?". Diaspora is a good example of the basic concept!


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So far as I have seen, there's no good paper-based way to represent this.

Some computer displays are pretty decent at it, with 3D-rotation controls and zoom-in-out features.

Otherwise... holo-display ftw!

edit: but as you allude in the OP ... this may not be actually a substantial issue... ? You liken it to plugging GPS into an airplane, and I think that's apt, particularly for Traveller-esque Jump drives - they are Point-A to Point-B and the intervening space is AFAIK largely irrelevant; even direction doesn't matter much except for how "everything that's a long ways off that-a-way" is closer to one another than any of them are to "stuff that's hereabouts" ... Jump/Wormhole/Etc has a way of rendering realspace / physical-proximity issues kind of irrelevant.

Of course, if you have a StarTrek-esque "Warp Drive" where you pass through (and potentially interact with) all the points along your path of travel,,, That's different! Then those maps get much more relevant.
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Colin Fredericks

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Sufficiently Advanced doesn't map space. In most settings you wormhole directly from planet to planet without leaving atmosphere. In the remaining one, you are broadcast from world to world at light speed, and the GM just lets you know how long you were in transit if it's important.


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Whenever people are looking at bogging down a game in details, they should ask themselves: What purpose is this serving? How is this making the game better? Are there better ways of doing this?

Why do you need a visual representation of 3d space in a 2d plane(hexmap)? You can have that 2d data listed out in charts/tables. You can use something like the original 2300 NSL and have X,Y,Z coordinates for everything. Then those coordinates can easily be translated into distances, which are easily translated into travel times. You don't need a 3d map, you just need those 3 axis data points, and you can knock yourself (and your player) out with that. Several folks online have gone through and made 3d models of the 2300 NSL and while they're nifty to look at, I'd never want to try to use them as a usable 'map'.

So you could go that route or you can decide that going through all that doesn't really add much narrative value, and plop down a 2d map and call it a day.


a.k.a. Mr. Meat Popcicle
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I used to use graph paper, orient a "north"/"coreward" then I used separate pieces that I stacked on each other to represent z. I labeled the x,y,z coordinates on the page, and it's orientation. Like page one might have been x (0-30), y (0-42), z (1) because my graph paper was 30 sq. horizontal, and 42 sq. vertical. But that was too cumbersome at the table, and even with the physical representations my players had a tough time visualizing locations. Eventually I switched to information tables for the coordinates, and this 3d distance calculator I Googled. Now I know that if Earth is at 0,0,1 and Adventure Planet X3 is at 17,6,2. If I think to myself "Hmm one unit is one lightyear", then based on those numbers I plug it into the calculator and boom I know it's ~18.05 ly from Earth.


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Even if you had a hologram projector to give you a completely accurate 3-D map, it's unlikely the player would actually use it to work out which star was closer to them, or which route was shortest. It's much easier to just calculate whatever values you think will be important and put them in a table, like real maps do with travel times between cities. If you want an illustration that gives some idea of the scale, just pick a viewpoint and do a 2-D map. Or pick two viewpoints at right angles, and do two 2-D maps.

Colin Fredericks

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Also: if your drive is fast and habitable planets are few and far between, it may be useful to know that the Milky Way is proportionately thinner than a penny. Hex maps are potentially not that bad if important things in your galaxy are fairly sparse.

The Wyzard

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I use a hex-map to keep track of where star systems are in relation to each other. That's the interesting part of travel time.

For in-system travel, I don't keep track of where things are within that three-dimensional space. I ginned up a system for it once and it was way too involved. You just need to figure out how long it takes to get from point A to point B, which you can do via some random factors plus something really basic like "inner system" or "outer system."

Getting from one inner-system orbital body to another is reasonably quick. Getting from a planet to its own moon is a very short jaunt. Getting from the in-system to the outer system orbital bodies takes a while.

If you can use an FTL drive inside the system, then travel times may be negligible.
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