Fractal random map generator

GregorR · Post by **GregorR** » October 2nd, 2005, 7:21 am

I've made a little fractal map generator (well, OK, modified one to spit out Wesnoth map files

) that I thought would be handy.

Basically, a program called worldgen outputs relatively realistic GIANT Wesnoth-style maps, then a program called chunk takes little segments out of it. That way, you can create one big consistant map for a campaign, then use little bits of it for scenarios. Or, of course, you could just make one map and use only one chunk *shrugs*

It doesn't put any villages etc on the map, that's up to you. It makes a pristene, pre-human pre-elf pre-dwarf pre-orc pre-other-sorts-of-civilization world

It also creates a .gif file (legacy from the original program), which makes a handy reference.

Enjoy, and please post comments

GregorR · Post by **GregorR** » October 2nd, 2005, 7:38 am

Of course, everybody loves screenshots, and I didn't post any, so here they are ...

It's the included example world, and a few selected areas from it in the Wesnoth editor.

scott · Post by **scott** » October 2nd, 2005, 10:54 am

Wow. Is that last one a wesnoth map?

ryn · Post by **ryn** » October 2nd, 2005, 12:14 pm

scott: the way I understand it, exa is the whole world of which exa_a and exa_b are pieces. Therefore, no.

Elvish_Pillager · Post by **Elvish_Pillager** » October 2nd, 2005, 2:01 pm

Why are there always forests between hills and grass?

Disto · Post by **Disto** » October 2nd, 2005, 2:09 pm

There aren't though....

Post by **Jormungandr** » October 2nd, 2005, 3:54 pm

This is pretty cool. Do you have any plans to expand it with either more command-line parameters, or to use more terrain types (I note swamps are lacking)?

And I'm pleased to see that the editor can actually load a 1000x1000-hex map without choking too horribly.

Post by **Dave** » October 2nd, 2005, 6:07 pm

Elvish Pillager wrote:Why are there always forests between hills and grass?

Yeah it looks like it's a simple height map with mountains > hills > forest > grass > sand > shallow > deep

I think if you're starting with a height map (and almost all map generation does start like this) it's best to just divide into mountains > hills > grass > shallow > deep and then worry about things like vegetation and snow afterwards using a different approach.

That's the way Wesnoth's current map generation algorithm does it.

The main nice thing about this map generator is that it does use a fractal algorithm. I think it'd be good to make that an option for the current generator -- to use a fractal height map generator rather than the 'hills' approach that is currently used.

David

GregorR · Post by **GregorR** » October 2nd, 2005, 7:00 pm

scott wrote:Wow. Is that last one a wesnoth map?

It's a .gif file representing a /huge/ Wesnoth-style map.

Elvish Pillager wrote:Why are there always forests between hills and grass?

As mentioned by others, it's a heightmap, so it's a pretty strange algorithm to make forests out of. There aren't always, but when there are it's because I translated "higher" into "forest"

Jormungandr wrote:This is pretty cool. Do you have any plans to expand it with either more command-line parameters, or to use more terrain types (I note swamps are lacking)?

And I'm pleased to see that the editor can actually load a 1000x1000-hex map without choking too horribly. Razz

Yes, of course. This is just a proof-of-concept. It would be nice to make one that diverged a bit from the pure 'heightmap" style, and hence could support other terrains, etc.

And no, the editor can't load a 1000x1000-hex map, that's why I made the chunk program

Anyway, I personally think that the nice thing about this is that it generates a very large map, so you could easily, for example, have one scenario on just an island, and then later come back and have a siege of that island on a larger map that also includes some of the mainland.

Anyar · Post by **Anyar** » October 2nd, 2005, 7:04 pm

GregorR wrote: And no, the editor can't load a 1000x1000-hex map, that's why I made the chunk program

Oh, it can. Took about a minute to load on my ibook. Hmm... I might try a 2000x2000 map...

Tomsik · Post by **Tomsik** » October 2nd, 2005, 7:22 pm

I think you can load as big map as long you have enough RAM.

Post by **Jormungandr** » October 2nd, 2005, 7:44 pm

tomsik wrote:I think you can load as big map as long you have enough RAM.

That's what it looks like to me, at least. Loading said 1000x1000 map took a minute or two, and about 300M of RAM on my machine.

Though, if you do this (and I can't think of a reason why you would want to, other than general curiosity) and then try to edit the map, the editor hangs for a while (as it recalculates transitions?).

Post by **Dave** » October 2nd, 2005, 8:02 pm

Yeah, it seems the transitions engine isn't very scalable to huge maps.

GregorR · Post by **GregorR** » October 2nd, 2005, 11:13 pm

Here's version 1.1. Now, rather than each level representing one terrain, each level has several different types of terrains, then it "grows" them to be consistant. It's not great ... but it's significantly better.

Also, for the lazy, it lets you add villages (optionally).

By the way, is there any way to turn a Wesnoth map file into a (possibly gargantuan) image file of the map?

Also, does anybody know of a C pseudo-random number generating function that's both decent and Free Software (GPL, MIT, whatever). It would be nice to put the randomizer in the program itself, so the same random seed will generate the same map on GNU/Linux, Windows, Mac OS X, Solaris, etc, etc, etc.

Post by **Quensul** » October 2nd, 2005, 11:33 pm

GregorR wrote:By the way, is there any way to turn a Wesnoth map file into a (possibly gargantuan) image file of the map?

Not sure if this is what you want, but Wercator is in a usable state - it can take a BfW map and render an ink-and-parchment version; see my signature for the thread in the forums, or go to http://gs295.sp.cs.cmu.edu/brennan/wercator/ for a web version. If you're planning on doing really huge files, I would recommend (1) only rendering the ink (i.e. no parchment, no frame) and postprocessing the parchment in, and (2) installing it locally, but see the forum thread and/or the Downloads page of the Wercator site for caveats. If you do want to render monstrous large maps via the Web interface, please run them after normal business hours (US Eastern time), since it's my office machine.

GregorR wrote:Also, does anybody know of a C pseudo-random number generating function that's both decent and Free Software (GPL, MIT, whatever). It would be nice to put the randomizer in the program itself, so the same random seed will generate the same map on GNU/Linux, Windows, Mac OS X, Solaris, etc, etc, etc.

Well, there's the GSL - it has a wide variety of random number generators available. I've been pretty happy with it for numerical simulation foo.