# World Builder's Handbook - Suggestions and opinions welcome

Hi Geir,
I just joined the forums and saw this post.
I have been working on this project for my own purposes, on and off for over a year.
I have been working through a great deal of material, as well as figuring out how to include/support earlier versions of Traveller.
I started with astronomy texts and support from friends who are studying this (benefits of living in a university city)
The article in JTAS 6 about how the traveller hexagonal map is a 2d mapping projection of 3d space (a great deal of the original article was left out due to space considerations and it being boring to non math types) was part of my project.
I have been automating the process I came up with as well, but, everything started with die rolling mechanics (including proper odds of haveing systems appear, based upon stellar density)
With the knowledge of a hexagon on a traveller map, being a cubic parsec, ie ~34.64 cubic light years, a single hex has more than enough room for multiple barycentres (a series of far systems, if using CT/MT terms) with each barycentre having the possiblity of containing one or more stars.
Then the stars have multiple zones, based upon temperature etc (simple black body emmision) and each zone can have multiple orbits.
So, if you are interested, reach out to me and I can provide you with my material.
I also included BioDensity/BioDiversity/BioComplexity for detailing biospheres.
I am currently working out the process of how to convert existing CT/MT/T5/MGT2 stated systems into

I've been trying to balance 'real' vs. 'game' systems for I won't even admit to how long, but since about when classic book 6 came out. To keep with playability and compatibility, a lot of what is 'correct' needs to be slimmed down - barycenters was I thing I wanted to do, but no, it's not possible to solve the n-body problem with a spreadsheet, so it had to get cut back to orbits, which I am modifying (or paying more attention to fractional orbits - which was always there), but I have to keep them for compatibility. Same with multiple stars in a hex. T5 allows up to 8 in a star system and I sued that, but its still a system a hex and a 2D space.

I did 'borrow' and modify the Bio stuff from the v1 Tools of Frontier living, which are fairly workable (but, sorry Colin, I sort of went my own way a little)

I've been trying to balance 'real' vs. 'game' systems for I won't even admit to how long, but since about when classic book 6 came out. To keep with playability and compatibility, a lot of what is 'correct' needs to be slimmed down - barycenters was I thing I wanted to do, but no, it's not possible to solve the n-body problem with a spreadsheet, so it had to get cut back to orbits, which I am modifying (or paying more attention to fractional orbits - which was always there), but I have to keep them for compatibility. Same with multiple stars in a hex. T5 allows up to 8 in a star system and I sued that, but its still a system a hex and a 2D space.

I did 'borrow' and modify the Bio stuff from the v1 Tools of Frontier living, which are fairly workable (but, sorry Colin, I sort of went my own way a little)
N-Body mechanics are not something to attempt to solve on modern pc's unless you want to watch the sun expand into a red giant while doing so.
No, I gave up on any attempt at "stable" orbital mechanics and made the assumption that what ever is generated is assumed to eventually become unstable but, not within the timeframes of the players/game setting.
ie what is listed is what is there at the time of mapping, but, that could change. Whole adventures could be based around that simple statement.

So, I split the hex into 27 zones, on a 3x3 grid, each zone is slightly larger than a cubic light year. but easy to think of it as 27 cubic light years.
Barycentres are "gravity depressions" which could be anything of any size, large enough to affect things within 10% of a light year from its centre.
Theorectically, you can have a gravity depression caused by multiple interacting gravatational wavefronts, without any local mass causing the effect. This can be like a lagrange point in the middle of nowhere (or other effects as well) The white paper and the math it was based upon is pretty new and I don't know how reviewed it is, but, it was quite interesting.

Depending upon the stellar density in the region, you first determine IF a barycentre exists, then you determine how many based upon density.
For example, earths solar system is in a bubble of low density, but the region outside that bubble has a higher density of matter.
Then, you roll for the positions for each barycentre and what is found there. (1d3, rolled 3 times, gives xyz)

Once you find what is at each barycentre, you go through the steps for populating that.
For example, if you find you are dealing with a standard class of stars, you know by the lookup table, it's mass, diametre etc. You also know the various zones and the average position of the first orbit. The table also lists the die roll for number of orbits.
I went with random vs fixed orbit distances. Each orbits, eccentricity, delination are all rolled for. This tells you the solar zones the orbit occupies as a orbit can cross zones for part of its orbit.
There are different planet types, etc., all rolled for. I used alot of highly modified material from MT WBH and T5 Book 3 but all brought up to date.
Most of this is setup to use profiles ala older versions of traveller but with expanded details that can be worked out in advance or on the fly.
So, yea, I worked alot of it out, along with an expanded version of explanator - I am currently doing up the svg graphics to simulate the output on computer screen for handouts.
I am not a wordsmith, so I never thought about typing it up for others, but, there is quite a bit of material there for you to mine if you wish.
best regards
Dalton

At least keep everything about the original (Megatraveller) WBH!

But also as you seem to be implying add in the Exotic Atmospheres JTAS supplement info.

Also I think it would be good to give some ideas on biospheres global and local: e.g
For orbits and the like don't get drawn into the rabbit hole of trying to simulate a system's evolution, orbits and dynamics - Traveller has always correctly been about emulating systems; creating a description that feels correct as a snapshot, not creating models that can be run in a supercomputer. I keep seeing people trying to replace the Scout 6 or WBH models with "accurate up-to-date" modelling based on current planetary system evolution theories because they feel that the model is "wrong" and quiet frankly it is a Category Mistake to go from emulation to simulation and believe that it is inherently better. If orbits are inconsistent with observations go the emulation route and add some variance that sometimes gives observed values.

Travellers will probably never be dwelling in freefall long enough for gravity and planetary motion to ever be any significant factor in any case.

At least keep everything about the original (Megatraveller) WBH!

But also as you seem to be implying add in the Exotic Atmospheres JTAS supplement info.

Also I think it would be good to give some ideas on biospheres global and local: e.g
For orbits and the like don't get drawn into the rabbit hole of trying to simulate a system's evolution, orbits and dynamics - Traveller has always correctly been about emulating systems; creating a description that feels correct as a snapshot, not creating models that can be run in a supercomputer. I keep seeing people trying to replace the Scout 6 or WBH models with "accurate up-to-date" modelling based on current planetary system evolution theories because they feel that the model is "wrong" and quiet frankly it is a Category Mistake to go from emulation to simulation and believe that it is inherently better. If orbits are inconsistent with observations go the emulation route and add some variance that sometimes gives observed values.

Travellers will probably never be dwelling in freefall long enough for gravity and planetary motion to ever be any significant factor in any case.
Yeah, the problem with simulation is that you need to run iterations, and Traveller is all about point in time. I've been down this road for a long time, doing this on computers as earlier as commodore basic, and even then I got into a loop (okay, so maybe I'm just a crappy programmer). But yeah, at some point you have to say "close enough" and move on. One thing in the back of my head is the issue of habitable planets around red dwarfs - maybe/maybe not, but for Traveller purposes, the answer has to be yes, or else there are too many habitable worlds and bad maps. In the end, its an RPG, a 45-year-old one at that - that fact that it's still a viable game is good enough.

I do deal with energy (well temperature), probably to excess. And life complexity, but not the kingdoms and classes at all. I want to got there, but I think that becomes another book - something like an evolved Animal Encounters fronted by flora and fauna creation rules. I have ideas, but not enough pages available, so maybe next book...

So here's the thing. If you did everything in the book so far (I'm up to 170 pages covering systems generation, then detailed SAH and then detailed PGL and all the ancillary stuff - starport, TL, culture, economics, military) it would take all day to do one system. Or a computer program, or a bunch of scripts.

There's a T5 concept MOARN - Map Only As Really Necessary - that needs to apply to worldbuilding. If the Travellers are just passing through, maybe UWP is all you'll ever need for a system. If you want to dive deep on a world for a particular aspect, I'm trying to make it so you don't have to dive deep for everything else, but just for the parts you need. A bit tricky and I've already tripped over a couple of examples where the DMs have made me go back and do more work. I'm trying to avoid that sort of thing, even at the cost of some 'realism'.

I may have mentioned in this thread that Orbits as a concept have to stay for compatibility and so does a 2-D simplified system. A real orbit has 6 parameters, but I'm intentionally only using 2 - semi-major axis (Orbits or AU or km, take your pick) and eccentricity; I mention inclination as an aside, but don't go into specifics on purpose. This is not realistic, but it's good enough for most temperature determination. Nothing prevents people from computing the other parameters and implementing them in their game, but that level of detail doesn't meet the 'Necessary' criteria. My goal for the relationship to 'real science' is to avoid creating rules that contradict reality or create clearly impossible results - I'm also hoping what I write doesn't fall so short of the actual science to be in the category 'Not even wrong'.

There's a T5 concept MOARN - Map Only As Really Necessary - that needs to apply to worldbuilding. If the Travellers are just passing through, maybe UWP is all you'll ever need for a system. If you want to dive deep on a world for a particular aspect, I'm trying to make it so you don't have to dive deep for everything else, but just for the parts you need. A bit tricky and I've already tripped over a couple of examples where the DMs have made me go back and do more work. I'm trying to avoid that sort of thing, even at the cost of some 'realism'.
I dislike that concept, and when playing in a VTT setting, find it actually takes away from game play.
With today's home computers being able to generate everything from the various dwarf planets orbiting in the outer reaches of a systems oort cloud, to generating a full branch of the local stellar arm, players want to be able to look at it as a fast wiki entry.
Trying to generate that on the fly, slows down game play and if you are trying to wing it, it ends up having players asking all sorts of questions that they could have answered with a quick reference to a wiki or printed pdf. (most likely a pdf on a smart phone.)
If a procedural approach is designed, before the week is out, you will have developers building it for thier own use and to share with others.
IF this was not the case, noone would care about the Travellermap, nor would they have all sorts of planetary map software.
While most players will never roll a single die to create a world, all of them will read about the different stars, planets, nebula and dream dreams of galactic empires with wild frontiers. The original WBH was packed full of reference tables and formula's, while just being an extension of the system presented in the core MT rules, but, it is one of the most beloved books for those who have it.
Most players will use an auto-generating program - I wrote my own and use it for my stuff, along with a javascript version of explanator that generates full text library data entries for the systems, worlds and everything encountered within that is marked as "explored" (you want to have secrets the players need to find)
So, with orbits, you want to provide all six parametres, even though you ignore them for temperature generation so that the players imagination and suspension of disbelief is maintained. With Barycentres, you don't calculate it, you place it and then set a system around it (even if it happens to sit within the boundary of one of the stars) you don't care about the actual mechanics as you are not building a simulation, but a model that can pass the muster of an old grey beard who wants to look up a term in wikipedia.
Elite dangerous has all the appearance of space engine without any of the underlying physics - just enough to let players enjoy the game.
So, lots of small die rolls and die modifiers, who cares, that is what software is for.
Having enough detail so that it feels like an actual survey team has entered the system and that you have a computer giving the players the details - that is magic.
Don't like formulas, use lookup tables, don't like pages of lookup tables, provide them as downloadable csv files so the book is not all tables.
Or put them into a separate book that is all tables (better idea as then you can read what a table means in one book while having the other book open to the table in question)/
So, details and mechanics are key - I created a spreadsheet to test out stellar density formulas before writing them down, knowing full well that anyone reading the work would do little more than give it a cursory glance and a developer would make it irrelevant, but, the fact that the tables are there, give weight to the work if for little more than to feel like this is as close to real science as you can get in an rpg.
It is your book, your production. From my standpoint, I will buy it as I am a completionist at heart, but, you have the opportunity to make this even better than the original MT WBH. It's up to you.

I dislike that concept, and when playing in a VTT setting, find it actually takes away from game play.
With today's home computers being able to generate everything from the various dwarf planets orbiting in the outer reaches of a systems oort cloud, to generating a full branch of the local stellar arm, players want to be able to look at it as a fast wiki entry.
Trying to generate that on the fly, slows down game play and if you are trying to wing it, it ends up having players asking all sorts of questions that they could have answered with a quick reference to a wiki or printed pdf. (most likely a pdf on a smart phone.)
If a procedural approach is designed, before the week is out, you will have developers building it for thier own use and to share with others.
IF this was not the case, noone would care about the Travellermap, nor would they have all sorts of planetary map software.
While most players will never roll a single die to create a world, all of them will read about the different stars, planets, nebula and dream dreams of galactic empires with wild frontiers. The original WBH was packed full of reference tables and formula's, while just being an extension of the system presented in the core MT rules, but, it is one of the most beloved books for those who have it.
Most players will use an auto-generating program - I wrote my own and use it for my stuff, along with a javascript version of explanator that generates full text library data entries for the systems, worlds and everything encountered within that is marked as "explored" (you want to have secrets the players need to find)
So, with orbits, you want to provide all six parametres, even though you ignore them for temperature generation so that the players imagination and suspension of disbelief is maintained. With Barycentres, you don't calculate it, you place it and then set a system around it (even if it happens to sit within the boundary of one of the stars) you don't care about the actual mechanics as you are not building a simulation, but a model that can pass the muster of an old grey beard who wants to look up a term in wikipedia.
Elite dangerous has all the appearance of space engine without any of the underlying physics - just enough to let players enjoy the game.
So, lots of small die rolls and die modifiers, who cares, that is what software is for.
Having enough detail so that it feels like an actual survey team has entered the system and that you have a computer giving the players the details - that is magic.
Don't like formulas, use lookup tables, don't like pages of lookup tables, provide them as downloadable csv files so the book is not all tables.
Or put them into a separate book that is all tables (better idea as then you can read what a table means in one book while having the other book open to the table in question)/
So, details and mechanics are key - I created a spreadsheet to test out stellar density formulas before writing them down, knowing full well that anyone reading the work would do little more than give it a cursory glance and a developer would make it irrelevant, but, the fact that the tables are there, give weight to the work if for little more than to feel like this is as close to real science as you can get in an rpg.
It is your book, your production. From my standpoint, I will buy it as I am a completionist at heart, but, you have the opportunity to make this even better than the original MT WBH. It's up to you.
I didn't say you couldn't do a complete system, I just said I don't want to make it mandatory. The extras are nice, but Traveller is still a tabletop RPG and computers need to be supporting tools (I used a spreadsheet with lookups to create most of the robots and would still be at it if I did it by hand) but if you can't play it with a few D6, it's not Traveller anymore, but Traveller derived. I sympathize with your point of view, and I will try to fit in everything to make it possible to do a complete detailed system if that's the direction you want to take it, but I don't want to make it a mandatory path. Since I mention all six parameters, I can add simple guidelines four the other four. Barycenters just won't work for anything other than the simplest cases without computer aid, and I'm betting the rules of thumb will work just as well in more cases than a set of formulas based on theory, but I'll look at it again next pass.

Agreed! I like a Top Down approach. You should be able to 1. Create a UWP only. 2. Using the UWP expand that to basic system info. 3. Using Basic System Info detail any world you want to excruciating detail...

So here's the thing. If you did everything in the book so far (I'm up to 170 pages covering systems generation, then detailed SAH and then detailed PGL and all the ancillary stuff - starport, TL, culture, economics, military) it would take all day to do one system. Or a computer program, or a bunch of scripts.

There's a T5 concept MOARN - Map Only As Really Necessary - that needs to apply to worldbuilding. If the Travellers are just passing through, maybe UWP is all you'll ever need for a system. If you want to dive deep on a world for a particular aspect, I'm trying to make it so you don't have to dive deep for everything else, but just for the parts you need. A bit tricky and I've already tripped over a couple of examples where the DMs have made me go back and do more work. I'm trying to avoid that sort of thing, even at the cost of some 'realism'.

I may have mentioned in this thread that Orbits as a concept have to stay for compatibility and so does a 2-D simplified system. A real orbit has 6 parameters, but I'm intentionally only using 2 - semi-major axis (Orbits or AU or km, take your pick) and eccentricity; I mention inclination as an aside, but don't go into specifics on purpose. This is not realistic, but it's good enough for most temperature determination. Nothing prevents people from computing the other parameters and implementing them in their game, but that level of detail doesn't meet the 'Necessary' criteria. My goal for the relationship to 'real science' is to avoid creating rules that contradict reality or create clearly impossible results - I'm also hoping what I write doesn't fall so short of the actual science to be in the category 'Not even wrong'.
Haven’t heard of MOARN before, but I do love the concept after your explanation!

A game does not need a complete real-time simulated universe if it all takes place in one single building.

Brilliant design philosophy!

Haven’t heard of MOARN before, but I do love the concept after your explanation!

A game does not need a complete real-time simulated universe if it all takes place in one single building.

Brilliant design philosophy!
MOARN works great, unless you are running a sandbox game, in which case it fails spectacularly.

MOARN works great, unless you are running a sandbox game, in which case it fails spectacularly.
For a sandbox, 'More' is 'Necessary'.
Okay, so that makes it entirely tautological. And me a wiseass.
But the point is for the system to be flexible enough to handle the amount of detail that you want to put into it. You definitely have to do more work to prepare a sandbox, or else your players need to be patient while you say 'hold on a second' (or wing it and write it down later).
I'm still pushing through to finish the first draft, and I had to put in a disclaimer that to do the social (PGL, St, TL and ancillary) stuff you have to at least roll through a full UWP to avoid getting into a loop. So there's no way not to make that necessary (ok, the minimum is actually: 'there's something in that hex', but THAT would fail miserably in a sandbox).

Have you ever seen games that use the hexcrawl model? The new T2000 is a good example.

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The notion that bereft of detailed rules for everything including barycenters and oort cloud compositions, most players will create their own maps and detailed simulations is simply not true. Maybe if your gaming table includes five doctoral students from the MIT astrophysics department. And even then, I question how much actual roleplaying time occurs at a table obsessed with such minute details. Players just want a playable game and fully appreciate the efforts made in Book 6, the WBH and their descendants.

Trying to appease every aspect of the hardcore crowd is going down a rathole that simply cannot be satisfied and still come out with a usable book. A playable 200-page book swells into a less usable 250-page book. The vast majority of players will be forced to skip over the six pages on barycenters, four pages on orbital eccentricity and three pages on oort clouds every time they just wanted to find out if the gas giant they jumped to was "large" or "small." A book that puts an emphasis on details that are not needed for 99% of players fails to serve its audience. Products have to be written with the user in mind; not the niche user, but the majority user.

Were this an online open-source software project, it could be created so that individuals could add their wishlists to it, but it isn't. It's an RPG book for a game focused on roleplaying with friends at the gaming table. Yes, the solo player, making characters, ships and detailed systems is part of the audience, but these books are written primarily with the gaming table audience in mind.

Geir's attempts to add some accuracy and make existing Imperial Atlas UWPs fit into the modern game as best as possible is all we need. Heck, this book will be a vast improvement on previous attempts. Geir knows his users and is writing this book to serve the vast majority of their needs.

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Here's an alpha (very alpha) version (image) of a Class IV survey form (let's see how attachments work with this new forum). Thing is, 30+ years ago, a paper form made sense. Now, not so much. So a tradeoff between making things fit on one page and extensible fields, is a little silly, but this mockup is a Word table (with tables within tables - lost three points of Sanity already).

(Before you ask, the Class III form covers the whole system, but it's too ugly too post right now)

Here's an alpha (very alpha) version (image) of a Class IV survey form (let's see how attachments work with this new forum). Thing is, 30+ years ago, a paper form made sense. Now, not so much. So a tradeoff between making things fit on one page and extensible fields, is a little silly, but this mockup is a Word table (with tables within tables - lost three points of Sanity already). View attachment 701
That looks amazing! I love all of the information that is involved!

Very boring, empty, but cleaner than my first attempt at the Class III Survey form for the whole system.

I like these forms. One thing I ask you to consider about every entry - how does that effect the player characters and the adventure?

Sure, listing Eccentricity is cool, but so what? is there something explaining what a high eccentricity means to the characters? If not, is it really worth including? THANKS

I sort of did it that way, there are small (which include Uranus and Neptune) Medium (Jupiter and Satrun) and large - superjovians to 13 Mj, which is the brown dwarf cut-off. I also added two atmosphere classes for oversized 'terrestrials' G, and H, helium-dominated and hydrogen dominated, so a world of size C+ could have an H atmosphere and be a mini-Neptune. All this is draft one (still ongoing) I'll need to work through it a few times to iron out how it works in practice rather than theory.
There is also a category of "super-Earths" that are basically tiny Gas Giants - more atmosphere than planet, but only a couple earth radii. That same sized world, located closer to the star, is a terrestrial Super-Earth. Tough to do Transitional worlds like that though...

I like these forms. One thing I ask you to consider about every entry - how does that effect the player characters and the adventure?

Sure, listing Eccentricity is cool, but so what? is there something explaining what a high eccentricity means to the characters? If not, is it really worth including? THANKS
Greater time variability travelling between planets. That can very much effect the player characters, specially if they have a medical emergency or someone is chasing them. Also this would come in very handy in the Pirates of Drinax campaign. Yay piracy! lol

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