World building using ArcGIS

[loogie]

Nothing better then using 20000 software for your roleplaying needs.
Sorry for the lack of pictures or screen shots at the moment, but i'm at school and don't have the project here

As i've stated in other threads, i'm in the process of creating a new realm.. start of which, i'm creating a world... Right now, i've come up with some basics for the mainland, and am planning to use ArcGIS to add the features in the world, so that they are geographically sound. I don't know how much everyone knows about Geomatics and analysis here in the guild, so i'll try to expain what I can...

First, to make most of my ideas work, i need to start with a DEM or Digital Elevation Model... what i've used for this is something people are firmiliar with here... Bryce... more admittedly I'm a novice at bryce, so i used photoshop to create a bump map, and added it into a bryce terrain... which i then exported as a USGS DEM. Playing around with the values so they made sense, i did things like added erosion, noise, smoothed etc... and the final product looks pretty good.

From there i imported it into ArcGIS as a raster. from here i can make contours and such, which i did, and found out that where the land meets the ocean (grey meets black) the countours were very square and ugly.. the contour above that looked quite good, so i preformed a calculation to lower the raster by 100.. (subtract 100 from the values)

after this, i had to make a polygon of the landmass (using the rasters contour) and made it a raster, then preformed multiply with the lowered raster (basically, the polygon raster had a value of 1 for land, 0 or everything else... and when multiplied with the lowered raster, it ends up with all the same values inside the polygon, and a zero everywhere else... (this is used to subtract everything below 0.

This is all i have done so far, but i have various plans for other things.

Rivers and watersheds
ESRI has a nice hydrology setup, which can allow me to find out what direction water will flow on every pixel in the raster... from that information we can then find where water would gather and run (rivers) on the entire raster... and when you give a point anywhere on the raster, you can extrapolate the watershed that point would fall under... this means i can create rivers on the world, using the DEM, instead of guess where they should be.

Climate
Climate is a bit more tricky, and has to start with placing points around the map with temperatures... A bit of guesswork here, and will be as detailed as you want to make it... but remember this is a fake place, so any "errors" don't have to be errors at all... from the points you can interpolate into a raster, and create a base climate for your entire map...

Plants and Animals
Plants can be found quite easily, using some simple analysis... basically, start with taking the slope and aspect of the DEM raster.. this gives you the steepness of the land, and the direction it faces... after that, its creativity... decide what your plants require to grow (some other facets and samples like soil types and such may need to be created, much like the temperature, but it is recommended to be more detailed)... with this information like for instance "cliff ferns require Xslope, and have to be south facing, on rocky soil and a temperate climate"... From the rasters we've created, we can preform an analysis to find areas that have all these attributes... giving you the areas this plan would thrive... from ther you can subtract any areas you wish (and add any areas) coming up with your final product... Same goes with animals, but you can also use the plants you create for their survival as well.

from that information, you can more easily create cities and regions, and populate your city in a human sense more completely. I believe using GIS software to figure out all this information is quite usefull, and creates a cohesive product, instead of finding conflicting ideas at a later date due to human error. The main thing to remember, is its fantasy... so nothing is an error, but being a geographer, i like my worlds to be as realistic as possible.

I hope this gives you an idea of what Geomatics and GIS can do for your roleplaying needs (and in the real world) any other ideas and suggestions would be much appreciated!

[Sigurd]

So the preamble sounds good.....











Lets see some maps

[GlennZilla]

I had a VERY limited experience with GIS back when I worked for the Water Resources Board. They used it to not only map the entire state but also estimate water flowing into and out of a watershed. They even used it to simulate the flow of water throughout an aquifer based on the geology of the area.

As a Graphic Designer I mostly used it to get eye catching maps for the various publications. It's an extremely powerful tool and I am anxious to see your results.

[priggs]

That's a very interesting use of ArcGIS! I like that you aren't guessing, but actually using physical geographical analyses to create the world. You could also use cost distance/ shortest path analyses between cities to create roads and paths. Cost distance could also be used to locate cities close to water and timber resources. And viewshed analyses to create watch towers with warning fires and/or burial or religious locations (for example, there was a study way back that found burial cairns to be related to the amount of open ocean visible and (if I remember correctly) visibility to each other, but I may be remembering incorrectly).

[ravells]

You should put this in as a suggestion to Torq's Guild Map project!

[Redrobes]

Hi Loogie,

This will be interesting to see what results you come up with. Many of the things you mention have been talked about (not so much on this site tho) especially the watersheds and the calculations of water flow.

I am part of a small group doing much the same thing but for Middle Earth. I remember one of the team mentioning ArcGIS - I think it might have been SeerBlue but I could be wrong. Anyway - the point of this project is to create a DEM of middle earth to a high degree of accuracy to the numerous reference maps and also try to conform to real geography as much as possible. You can take a look at the progress here - www.me-dem.org

I like what your saying with the ideas about calculating RPG stuff from physical properties. I was mentioning this a while back in another thread - here you can check out the whole thread for a little more but these musings were a little bit of a distraction from the general map discussion.

Well, I am in anticipation of some nice pics

[su_liam]

Given the economic impact of a tool like ArcGIS, I'm impressed by the work, but might not find it altogether useful. Except for the, always fun, "gee whiz," factor. A good Bonehead Guide tutorial on the use of GRASS for things like this would be most appreciated, however .

Keep up the good work, though, and be sure to send pictures.

[loogie]

Well here are some real quick ones... first, the export of the world from photoshop... theres some editing i needed to do to get things just right, but since this was already a jpg, i figured its easier then exporting in bryce.

the second is a screen from ArcScene, showing the continent in 3d, blue background just so you see everything better...

and finally, an screen from ArcMap, after i ran the flow direction and flow accumulation tool, you can see the rivers are coming along nicely. Lakes however will be a bit of a question... i'll have to use the flow accumulations to find out where water runs without going anywhere, and basically work out how much water and therefor how high the lake will be...

[loogie]

lol i found grass earlier this month downloaded it and... well.. didn't touch a thing after that.. i have no idea how to use it, but if i got the basics down, and this type of analysis was available, i'd be happy to

[su_liam]

I was hoping someone who had a basic grounding in using at least one GIS program might be able to help me figure out how to use this thing. It seems promising as hell and you can't beat the price, but I can't even figure out how to load a raster.

The quick starts I've found seem to assume a basic grounding in GIS.