Sometimes I just want a quick method to generate terrain for a planet. Being a simple and fast procedure, it comes with the cost of the world not being as detailed or realistic as othe rmore intricate methods, so keep that in mind; in any case, let me show some examples of planets
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Attachment 137787
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Cartograph Guild.png
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Cartograph Guild.png

This method allows us to get some basic continents with some 'mountain ranges' added into the mix, some even getting near the coasts. Far from being realistic, but it is a quick method, meaning you can more easily attempt different results if you don't like the final one. Finally, I will apply the method as in a way to generate terrain for the whole round planet, but you can adapt it for more local maps, if you will.

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STEP 1
Given that the idea is to generate a whole planet, I like to work with 2x1 maps. I will use dimensions of 3000x1500 here. Once you have your blank canvas, first thing is to go:
Filter -> Noise -> Spherical Fractal Noise
We'll use the Ridged Multifractal type, with Replace operation (those are set by default when you start the program).
In the octaves setting, I usually click the "BL" button next to it and leave the value it picks; I'm not sure, but I think Wilbur take into account the dimensions of your map in order to pick a good enough value for detail here? In any case, for a 3000x1500, it sets the value 9.5507.
I like to change the values for Sphere Radii to 1, all of the three dimensions.
Finally, come up with a random seed for RandSeed. Different seeds will give you different planets. I will be using 7515685 here, just for the sake of clarity.
And that's it for this first step! Just hit ok, and you should have something like this:
Cartograph Guild.png

STEP 2
This generated Ridged Multifractal will be the basis for our montain ranges. it might not look like for now, but this function already generated some nice ridges for us... we just need to "uncover" them out of this mess. Best way I know to do it? Exponents. Lots and lots of exponents. So, go:
Filter -> Mathematical -> Exponent...
Given that all your land will be above sea level after step 1, this is the only parameter you need to care here. Now, setting this parameter to 10 will give you a nice result in one single go... you will see that most of the map is flattened, leaving only some altitudes around some ridges. The higher you set that parameter, the more evidenced these ridges will be. I want them to be evidenced, but I also want the surrounding terrains to contribute to the final result too, so a parameter of 8 or 10 seems to be a nice middle-ground between the extremes. After you're finished, you should end up with something like:
Cartograph Guild.png
Now, let's just change some parameters of our current terrain before we add another pass of noise. This is what we'll do:
Filter -> Mathematical -> Span of 0 to 3

STEP 3
Time to add our new spherical noise
Filter -> Noise -> Spherical Fractal Noise
This type, we'll be using the Hetero Terrain type, and we'll change the Operation to Add. We can leave other parameters as they are (octaves set to BL, sphere radii set to 1). But we can also throw a some variety into the mix. We can do this in two different ways: we can either set a new RandSeed for this noise function, OR we can simply change the Sphere Center parameters. In my case, I'll leave the RandSeed the same value (7515685), and will change the Y parameter in the sphere center from -10 to 10. You can choose any combination of numbers here, just like my choice of seed, I'm just telling you my specific numbers for clarity.
And that's it for this step, really. Just add a Hetero Terrain, change some generation parameters (seed or sphere center) for more variety. Hit ok and you should end up with:
Cartograph Guild.png

STEP 4
We're almost finished; let's just do some final tweaks in order to make our map easier to work (at least in my opinion...).
I like to do another span:
Filter -> Mathematical -> Span of 0 to 1, this time
And now, I do small steps of
Filter -> Mathematical -> Offset(Add) with a parameter of "-0.1".
I just repeat the offset over and over, while juding the results, until I get a nice mix of oceans and dry land. In general, they tend to appear between the 4th or 5th pass, but I like to check them step-by-step anyway, you never know... a lot of the times my favourite stop are "between" steps here, though; in cases like this:
Edit -> Fade to Prior is your friend. This function basically "blends" your current terrain with the terrain in the last step. I will do one with a 0.5 amount.
Now, let's do some scaling :
Mathematical -> Scale, single value of 15000 (I actually used 30000 for the examples above, maybe that was a bit too much). The final resut is:
Cartograph Guild.png

And there you have it. It's rough and not very realistic, but it's quick and hopefully easy. It's all a matter of exploring different seeds and parameters to check the results.