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View Full Version : [WIP] Please critique the continental landforms



Master TMO
02-13-2012, 01:48 PM
I've come up with another script idea to test out. This world started out as a standard Fractal Terrains 3 randomly generated map, with no manual tweaking. The script is an attempt to fix FT's normal result of continents with central mountain ranges.

Please take a look at this and see if the landmasses look reasonably plausible. There has been no manual modifications made, all with scripts and standard menu options (and a simple selection modification in Photoshop). Please feel free to point out anything you think doesn't look realistic. I freely admit that there was no attempt to define continental plates. I have no doubt there are plenty of issues with it.

42207

Thanks in advance for any feedback.

Master TMO
02-21-2012, 09:09 AM
Hmm... Apparently, while we have a very active River Police Squad, we have yet to develop a Continent Police Squad. :P

For my own critique, I think that, due to the way the script runs, the mountain ranges enclose too much of the continents. They tend to go all the way around the edge, rather than being just on 1 or 2 sides of it.

bartmoss
02-21-2012, 02:06 PM
The continent looks good for a random script, but I don't buy it as "this could be earth". You are right, the continents are too "enclosed" by mountain ranges.

Master TMO
02-22-2012, 05:23 PM
A couple of modifications to the script, and it looks much better. I am not sure if it has reached 'believable' levels yet though...

Feedback would be most welcome. What looks wrong about it? Much obliged!

I can see it still has some issues with areas where the inland lakes had been, but those are okay. Fixing those wasn't the primary goal of the script. More believable mountain ranges was.

42437

Master TMO
02-23-2012, 01:48 AM
This version is probably easier to see the various elevations. It does not have the editing the color map above does - no incise flow, filling basins (multiple times), smoothing (multiple multiple times), and rivers. This is the map just after the script finishes.
42450

And, for comparison, here is the original base map, with no changes. I am flipping back and forth between the two, and can't quite decide if I'm happy with how it works, or disappointed it didn't do more.
42451

I should probably run it through more paces before deciding. Bounce it against a few more random worlds, see if it works right or not.

(PS - It's a good thing I previewed the post before submitting... the images were in the wrong order. ;) )

Lukc
02-23-2012, 03:13 AM
Well, you have the classic problem of fractal terrains - they don't look like there have been plate tectonics going on. Otherwise they look ok, if'n you're asking me :)

If you want plate tectonics, though ... different kettle of phish. :)

Master TMO
02-23-2012, 07:21 AM
I was aiming for a way to get at least closer to a semi-plausible layout, from fractal to plate. What the script does is play with the roughness factor, starting low from the coast and rising upward to a peak, and then lowering again back to the low. The idea was that it would put the mountain ranges at the edges, and plains in the center. The first script took that too literally, and you can see the mountain ranges completely enclosing the continents on all sides. The second script is actually almost exactly the same as the first, but the starting selection is changed, so that it is related to the shape of the landmasses, but not identical, throwing the edges off-kilter enough so that it isn't obvious what's going on.

Some of the good points of this second version are visible up north: a lot of the land got flattened out, and in the upper left is an isolated straight mountain range. There are also a couple of other areas where the ranges were separated from the main mountain range.

You can see a few rifts in the sea bed where the script operated. I don't worry about making the sea bed realistic, so I consider those an acceptable side-effect of Progress. :)

Also, I just realized that the selection I used for this run did not have the lakes taken out of it, so it technically wasn't quite correct. I've run it again, and this time am running a fill basins to get rid of the visual confusion of those lakes. I won't do a full production on it though, just enough to clear it out and make it easier to see how it is.

And I do appreciate y'all putting up with me and my continual experimentation. Most of them don't turn out the way I want, but I figure if it was that easy, someone would have done it a long time ago. :D

atpollard
02-23-2012, 09:33 AM
The continents lack a center. Earth's examples ... North America, South America, Africa, Australia, Asia, Europe and Antarctica ... all have a distinct 'center' around which you can draw a circle or ellipse and select most of the area of the continent. Sure bits and points stick out, but there is a distinct, roughly round 'center'.

North America: centered on the Great Plains.
South America: the Amazon bulge in the north.
Africa: The northern bulge centered on the southern Sahara.
Europe: Centered on the German-Swiss border.
... you get the idea.

Your continents are too 'stringy' - more like large irregular islands - with too many internal areas lower than sea level. (The number of places below sea level - excluding the oceans - is staggeringly few on the real Earth.)

Once you have a central continental mass, Earth seems to have mountains around one or more edges of that mass - almost at random how many sides have mountains. One algorithm for all continents (without some randomization factor) will probably have limited success at creating 'realistic' continents.

I hope that this helps.
Arthur

Master TMO
02-23-2012, 09:32 PM
It does help, thanks. Part of the cleaning up process on a world involves filling in all those interior seas, but I just hadn't put that work into those particular maps. Doing so won't really fix the issue you point out, of course. ;) But it will look a tiny bit better.

Master TMO
02-23-2012, 11:56 PM
Ah, just realized an issue with the color scheme I used in those images, that is probably confusing things - the altitude color scale is relative. White is the highest altitude on the surface. Whether it's 32000 feet, or 10000 feet. So two different maps will have most likely have the same elevation shown as two different colors.

gwiley
02-24-2012, 01:13 PM
For myself, I like the 2nd one better. I do not have a problem with the mountain ranges. Earth plate tectonics would have an ancient continent that splits and wanders. And, of course, they "fit" together. But that is here and elsewhere, perhaps different. I would expect more land mass unless it is more of a water world than Earth.

I like the darker colors and that they are different shades. I did not associate it with elevation. Perhaps because you have only a few variations. I would add more shades as the color scheme suggests every place is almost the same. I would add more mountains but I am a tectonics freak.

Two things bother me:
- the color of the oceans - too uniform even though you have depths well done. Your trenches are almost stand alone - usually I think of them as being close to continents.
- the rivers (does this make me an honorary river police?) - at a continental scale, rivers look more straight - yours are too straight for my taste. again, the uniform color bothers me.

Otherwise, the script you are using makes a very nice map.

Regards,
Gary

Master TMO
02-24-2012, 08:50 PM
The nice thing about Fractal Terrains is that I can swap out color palettes with the click of a button. And I have a very bad habit of just swapping around schemes and posting maps here with no explanation of what the colors mean. :?

The primary goal of the script was to try for a more realistic set of mountain ranges, towards the edges of the landmasses rather than in the center where fractal generators tend to put them. The sea is underplayed because it's completely secondary. I am more concerned with the surface. The trenches were, in fact, a completely accidental side-effect of the script. Also, the rivers are standard Fractal Terrains output to show the slope and direction of the land.

The second color scheme was one that I might use for a finished world, since I had put some work into it just to show what a processed version of the script output might look like. The first and third were primarily to show the elevations.

Thanks for your feedback, I appreciate it! I can very easily get carried away with my own ideas, so I like to let other people fact-check me and bring me back to reality occasionally. :D

Robulous
02-27-2012, 03:47 PM
Well, you have the classic problem of fractal terrains - they don't look like there have been plate tectonics going on. Otherwise they look ok, if'n you're asking me :)

If you want plate tectonics, though ... different kettle of phish. :)

I agree about FT and plate tectonics - of course not all worlds would necessarily have tectonics, Venus and Mars don't, but then they're not habitable.

Is there any other software that would help model continental plates? I have an FT world model which I have drawn plates onto, but it would be cool if there's a tool I can use to play around with them.

Master TMO
02-27-2012, 04:55 PM
I agree about FT and plate tectonics - of course not all worlds would necessarily have tectonics, Venus and Mars don't, but then they're not habitable.

Is there any other software that would help model continental plates? I have an FT world model which I have drawn plates onto, but it would be cool if there's a tool I can use to play around with them.

None that I am aware of. There have been a few mentions on here of people trying to build tools that start at modelling them, but none have finished that I know of. I have an Excel sheet (http://www.cartographersguild.com/showthread.php?15487-WIP-Tectonic-Plate-building&p=162223&viewfull=1#post162223) of my own that tries to divide a sphere up into random plates. It's not very well tested yet, and has been running for the last 24 hours now, trying to output a 4096x2048 image of a world with 17 plates on it. I had the thought the other day of combining that project with this script and seeing what kind of results I got.