They are brushes, and they're actually all placed above the water level. They just happen to be so large that they can extend into the water. You can test this out yourself; go in the system editor and set the water height for a moon to 100. You might be surprised to find that the craters disappear.
Is the rule (no brushes below sea level) based on the origin point of the brush, if not, what? And would it be possible to have one simply extend below the origin point to make seaside cliffs?
Yes and no. The problem with having one extend below the origin is that you won't necessarily get a flat base to the cliffs. It could cause a number of problems. I talked about that a bit in the cliffs discussion, the top left / top right quadrants here demonstrate: I actually already have this problem with the mod (thankfully it isn't too severe though), because it uses a brush that extends a little ways below the origin as well (it was the best I could find from the files though).
Does the terrain generation allow you to choose different brushes based on the height of the terrain? If it did, that would allow you to have different cliff brushes and pick and choose them based on what is needed for that specific terrain height.
You could prevent cliffs from ever being stuck in the ground. Take the height at the center of the brush, then choose a brush for the appropriate height, and place it. You shouldn't have anymore unwanted dents in the ground. (If the system allowed you to do it that way, that is...)
Interesting, in that point then, just curious dude, are you able to change the colour of lava itself? or even add bloom to it? this is something I've been asking for quite some time now on the forums with the usual non informative reply's since last year from uber strangely enough when it comes to the lava planets. Is it possible for you to enable that kind of lighting? or get close to that sort of terrain around the lava with this mod? I think this has been talked about already in this thread when you're talking about having the brush not able to go below sea level but wasn't sure if this also refered to the lava? see this picture I wouldn't call cliffs so much as more like lava pools in the middle of terrain.
Why this has to be a mod is beyond me, this should be a basic terrain feature. I'm hoping it's only because they haven't got around to making it yet.
According to them, it is only because they haven't gotten around to it yet. (though apparently they were working on it)
So the planet loads up in my editor just fine, but when I load it on the server it just spawns a planet with bumps and just ground textures. It doesn't load the lava or cliffs or other features. Am I doing something wrong.
The system does not allow that, and I seriously doubt that could work. Again, it depends mostly on the slope of the terrain at and around the location; not the absolute height of the terrain at that location. Brushes can't be placed below the water level; this is true regardless of whether there really is water. As for altering lava; when I was talking about lighting, I was referencing the lighting settings for a planet (the sun's light intensity and colour, the ambient light's intensity and colour, etc). I haven't looked into how the lava self-illum settings are defined, but I might.
You'll need a high height range to get large cliffs. Try around 85. This is because the current terrain height algorithm and the cliffs don't really play all that well together; you can't have flat ground with large cliffs, since you need a large height range for large cliffs and at large height ranges the height map will be very wavy / bumpy. There are 2 mods; a client-side one for the system editor, and a server mod part. Sounds to me you only have the client side / system editor part.
Would you mind giving an example of one of your planets? If you still have them saved. (Their settings)
There are 2 mods.json files; one for server mods, one for client mods. You're certain it's reference in the server_mods mods.json file?
I usually have water height around 40, height range around 85-100. Temperature depends on what kind of forest I want the most of (warmer = jungle).