Shape of the VS Universe

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Zeog
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Shape of the VS Universe

Post by Zeog »

I am in the process of building some improved mapping tools for VS (mainly better visualization of statistical data). There I wondered what shape the VS universe has and whether or not it is feasible to project it down onto a 2D map. So I did some analyses:

There are currently 5702 systems in 58 sectors with a maximum extension of 1940.846233 x 2154.009431 x 1003.328731 (size in x,y,z-direction) in to me unknown units -- maybe light years. Sol was chosen as the origin of the coordinate system.

Attached is a plot of the spacial system distribution (projections).

What ones can see clearly in those plots is, that centered around Sol there is a sphere of great system density surrounded by another one of lesser density. The rest of the universe is a rather boxy structure of quite low but homogenious system density. Beyond that the universe is empty (apart from a few single solar systems in the remaining part of the box structure).

A 2D mapping for such a system distribution is clearly not feasible. Personally, I don't find the current shape of the universe to be very appealing.

I have heard that the VS universe is basd upon real solar system data, is that true? If that's is the case, there is the chance of extending the map, since today there are many more known positions of stars (speaking of some hundred-thousands). I know of the 2dF-Galaxy-Redshift-Survey listing already millions of galaxies.

Are there thoughts of making the entire VS universe generated procedurally? That could provide a more homogenious distribution and an arbitrary (virtually infinite) size, or at large scale a real galaxy like structure featuring sprial arms and all that (which I would really love to have). I have once played around with Perlin noise and some well chosen functions to make such a galaxy shaped, cloud-like structure featuring spiral arms, a core region etc.
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jackS
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Post by jackS »

Interesting. It's intended to be 3200x3200xWhatever. Clearly something was a bit awry in the generation or, ( though I find the former more likely) with your analysis. There are, however, 64 sectors - of this I am quite certain - here they are, in fact, as currently named.

Code: Select all

RBL-1   	RBL-2         RBL-3	  Eeyenjylk	RBL-4	      RBL-5	    RBL-6	      RBL-7
RBL-8   	Gohthuhthuh	Uulmm	  Aeneth	   Uumghemm	   Eeruu	    RBL-9	      RBL-10
RBL-11  	Alleethuh     Ouulneh	Gohallruu	Mahgoh	     Thuhtmaah	RBL-12	     RBL-13
RBL-14  	Iyn           Maeell	 Eilthut	  Eilgohall	  Miyeeldah	Ibzazz	     Zzyqqh
Thanatos	Rust      	 Solace	 Redemption  Ingatwa	    Ahbz	     Pzzaztahber	Bzzeen
Diaspora	Torkelsen 	 Magellan  Crucible	 Bribztkaber	Bztutpt	  Aantlbzz	   Aantutpt
Vormund 	Vega     	  Sol	    Beckett	  Izzptipt	   Bzzahbtktk  Ibpzez	     Ahbzeentk
Rhubarb 	Plymouth	   Baja	   Caldera	  Tutbzzaz	   Eebzpt	   Ohzzz	      Ailzzptpt
The blob around Sol is the only place where real star data is being used. This will eventually be expanded. The expanse of the map itself is not currently scheduled for increase, so, no spiral structure is going to be visible on this scale.

It would be interesting for you to also plot the density of the reachable star systems. You should note a much greater dropoff in the density around Sol relative to the rest of the map.

I would appreciate it if both tools were made available to the developers before we next regenerate the game map.
Zeog
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Post by Zeog »

Concerning those missing sectors: I found only 58 of them because the remaining 6 are not listed in the current (downloaded last week) CVS milky_way.xml, namely:

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RBL-1   RBL-3   RBL-4
RBL-6   RBL-7   RBL-14
Could you check the number of star systems? Since the extension of the universe is clearly not 3200x3200x??, there might have been an error in the creation process of the universe data. Is there a different version of milky_way.xml?

The extremum values of coordinates found:

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coordinate                 x            y            z
min. coordinate value  -489.254299 -1715.482681  -479.003428
max. coordiante value  1451.591934   438.52675    524.325303
size                   1940.846233  2154.009431  1003.328731
I'm now going to start doing the analysis for reachable systems only. These are caracterized by having a jump point, right? I'll also try a connection analysis to find out whether or not there are two or more regions that are internally connected, but disconnected from each other.

The drop-off in density you want me to find is quite big already. The plots' color intensity and equi-denstity lines are plotted on a logarithmic scale! (The blue region features very few stars per pixel and the core region hundreds.)

Those tools I'm using, are not really tools. Currently it's merely a python script that does the data crunching by walking through the milky_way.xml-file and finally drawing three plots. It's a quick'n'dirty-kind of script, not really sophisticated. But I could send it to you guys if you want (after a little refinement of course ;-) ).
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Post by hellcatv »

maybe after you finish with this tool, you can generate data that's more akin to the universe jacks desired---and *also* contains information about the stars around us

:-)

make sure you're using the latest milky_way.xml

http://cvs.sourceforge.net/viewcvs.py/* ... l?rev=1.22
though that's 11 months old--probably just dandy

-Daniel
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http://vegastrike.sourceforge.net/
jackS
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Post by jackS »

Zeog wrote:
The drop-off in density you want me to find is quite big already. The plots' color intensity and equi-denstity lines are plotted on a logarithmic scale! (The blue region features very few stars per pixel and the core region hundreds.)
You misunderstood me - when you plot the reachable systems, the area around Sol will become much less dense while everything else will remain at similar density, hence a significant dropoff around Sol relative to the dropoff in other areas (although I'd be surprised if the density wasn't still much higher around Sol - we were quite sloppy in generating the map).
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Post by dandandaman »

Zeog wrote:Those tools I'm using, are not really tools. Currently it's merely a python script that does the data crunching by walking through the milky_way.xml-file and finally drawing three plots. It's a quick'n'dirty-kind of script, not really sophisticated. But I could send it to you guys if you want (after a little refinement of course ;-) ).
Sure, I'd still like to play around with it :-)

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Zeog
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Post by Zeog »

Dan.a, here are the two Python scripts I used.
The first one extractData.py parses milky_way.xml and extracts all data that I needed. I redirected its output to a file.
The second one simpleStat.py does a tiny analysis, i.e. min/max coordiates and the binning for those graphs. (You need the SciPy-package in order to use the graph routines. Therefore I commented them out.)

Futher, a more extended analysis (script is being debugged currently) indicates, what jackS already said. Of those 5702 systems found in the milky_way.xml there are 3267 isolated systems, i.e. having no jump connection to another system. They also have no faction assigned to them (so nobody is stuck :wink:). The remaining 2435 systems are all connected to at least one other star.
Some more info on initial system ownership:

Code: Select all

771 (32%) by rlaan      98 by shaper      23 by highborn   15 by ISO
705 (29%) by aera       37 by unadorned   20 by forsaken    6 by shmrn
199 ( 8%) by purist     31 by pirates     19 by luddites    1 by dgn
159 ( 7%) by LIHW       29 by mechanist   18 by confed      1 by merchant
149 ( 6%) by andolian   26 by uln         17 by klkk
111 ( 5%) by unknown
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Post by dandandaman »

Cool! Thankenyou muchly :-)

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Zeog
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Post by Zeog »

Alright, I can confirm that these 2435 systems are all being connected directly/indirectly to Sol, i.e. there is only one connection compound.
The sectors have a boxy shape. The jump line plot shows, that the connection within sectors and between sectors varies quite a bit. (I don't think it is worth the effort to quantify that, though :wink:)

Plots are attached.

For the next version of the VS universe I was thinking of another way to connect systems: I plan on jumplines between next neighbor systems. This results in doing a Delaunay triangulation. As a bonus you get a Voronoi tesselation almost for free. In 3D This requires some tricky math and will take me some time. But it will be very beautiful! Look here: in the context of fluid particles
(Different connection algorithms could additionally be included.)
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jackS
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Post by jackS »

Zeog wrote: The sectors have a boxy shape.
As mentioned before, we were sloppy :-(
Zeog wrote: For the next version of the VS universe I was thinking of another way to connect systems: I plan on jumplines between next neighbor systems. This results in doing a Delaunay triangulation. As a bonus you get a Voronoi tesselation almost for free. In 3D This requires some tricky math and will take me some time. But it will be very beautiful! Look here: in the context of fluid particles
(Different connection algorithms could additionally be included.)
That would be pretty, but I'm not certain that it's what we're really looking for - see the other thread discussing this. To summarize, unless I am not understanding your proposal, the deviation in degree for vertices is likely to be fairly low.
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