How to create realistic mountain ranges?

OnlyBone

Hello guys,
I am currently trying to create a mountain range for my terrain project (using Instant Terra, but if you are using other software please share your approach still!) but I am struggeling with getting it to look belivable.  What I am aiming for is something resembeling this:


The closest I have gotten is this:


As you can see, the erosion it self is actually pretty much alright, but since I am working off of basic noise strictly, the hill placement seems very illogical. 
In the first picture, every large scale ridge follows a very defined path, and their neighbouring ridges follow more or less parallel. Additionally there are very few, if at all, "landlocked" pockets, but every vallye "flows" from one to another.
In contrast to this, with my attempt, each "ridge" is more like a standalone mountain, and the valleys created are pretty much never interconnected with one another but rather form lakes/pits.

How do you guys would try and achieve that look, without resorting to real world data?

Klunk

what's the issue with real world data ?

Alex_J

if you wont use real world heightmaps from terrain party then you probably ought to study real world geography and then you can paint a basic heightmap to lay in the general shape, or if that app lets you manually draw elevation do so. Basically define the high ground and from there you can do water simulations to erode the valleys.

You probably just need a lay persons understanding of geography to lay in the largest forms in a believable way and then let the erosion sims do the rest.

what you've shown wouldnt read as unrealistic to me because in the middle of a mountain range it is perfectly possible to have some standalone mountains. You can study the scale of major terrain features on google earth. it will be different from one mountain range to another. So the measure of kilometers from one side of valley to the other in say, the Dolomites might be a very different scale compared to the Andes or the Himalaya or the Rockies. And the average size of base of the mountain, and if you have one continious ridge versus more solo peaks, etc.

i have been using world creator which allows you to use a brush to paint in the major shapes, if you want. probably most of the terrain apps allow something similar, or you could start by importing a heightmap which you could author in photoshop or similar. But using real world heightmap is the best thing to do in any case i could imagine.

OnlyBone

Klunk said:

what's the issue with real world data ?

There is nothing wrong with it per se, but since my Terrain isnt based off of Something found in the real world i figured it would be easier to do them from Scratch and Tailor them to my needs.
Here is the original Forum Post i Made over at ITs own forum to give you a little context to the Terrain i am trying to create https://www.wysilab.com/forum/index.php?topic=363.0 but i havent gotten any responses there.
Currently in mobile so i cant provide more Pictures unfortunately

Alex_J

you could try overlay details from real heightmap on top of your hand painted one. This way you get the basis for erosion channels but can scale and rotate it to fit with your desired larger shape. Then use the programs simulations to add the finishing details

Benjammin

Consider that your erosion is caused by water - where does all the water go? I can see you've got the suggestion of some lakes in there, but unless there's underground drainage, those lakes would get higher and higher until they spilled over the lowest hills and carved channels. 

Can't help you with how to achieve that in your software, sorry

OnlyBone

I feel like what Alex has said will be what I am going to need to resort to, but there must be a way to recreate these hills artificially or not? The problem with erosion in Instant Terra seems to be that it isnt made for large scale erosion but rather to add detail to an already set layout of major terrain features, instead of creating those through erosion.
Here are some examples of different erosion computations repeated serveral times to try and create the effect Benjammin described.

Base terrain:

Multiscale Erosion:

Hydraulic Erosion:

Thermal Erosion:

Thanks everyone for the suggestions so far!

@Alex_J could you maybe show me how you do it in World creator? Maybe there is something I can transfer to IT..

Alex_J

I have not used world creator for a minute, but it looks like newer version they've added some sculpting brushes:

https://www.youtube.com/watch?v=FhrNne70yII&list=PL-T0P8fE0hYrulft9PLKV90UxxfH0AH-m&index=9

i think similar was there previously in versions i used, but it was more basic.

But you can essentially do the same thing with your heightmap in photoshop, it will just take some more back and forth. I'd bet instaterra probably has tools for sculpting or heightmap editing but you'd have to look it up, I am not familiar with it.

Basically if you paint heavy white for your largest terrain features, then you can cutup real world heightmaps for the smaller details and composite it in photoshop or similar. You might be able to do the compositing right in the terrain editor, just search what sort of heightmap editing tools it has.

So long as you get the basic scale of terrain features, the simulation should take care of all the details.

the way these things work is that they are just editing a heightmap, and then the heightmap is used to displace the terrain which gives you the visualization. So as long as you understand how that works you'll be better able to get the result you want.

OnlyBone

Okay, IT has similar capabilities, they are Just Not as convinient to use Like shown in the video. And I do know what heightmaps are and how they work, I also already tried painting them by hand but it Always feels very artificial and I am never quite happy with how they Look in General. Maybe i Just have to git gud with Gimp i guess...
I Just thought that since These Programms were made specifically for Terrain creation, they would already have Tools that Take Care of that.

Benjammin

Try giving the tool something to work with besides a flat plane.
Define these sorts of shapes, whether by sculpting in the tool or drawing in GIMP/PS. Don't even think about them looking natural or correct. Then apply all your noises and erosion to that. 
If you were building terrain for a game environment, you need to define paths and play spaces anyway. Also bear in mind its never going to be 100% accurate because nature is doing it with atoms, over millions of years. You don't have that kind of time or resolution
Unless you're making a flight sim, a lot of realism issues disappear when you're at character scale. 

OnlyBone

Benjammin said:

If you were building terrain for a game environment, you need to define paths and play spaces anyway. Also bear in mind its never going to be 100% accurate because nature is doing it with atoms, over millions of years. You don't have that kind of time or resolution
Unless you're making a flight sim, a lot of realism issues disappear when you're at character scale. 

Well, whilst Im not building a map for a flight sim, you still have an aviation element to it. Its supposed to be for ArmA Reforger and its going to be fairly large at 32km x 32km, so players will definately fly over the map. But yeah, I guess I am going to have to experiement more with hand painted stuff..
Thanks for all the suggestions so far!