Download https://github.com/paramat/levels/archive/master.zip
Code https://github.com/paramat/levels
For Minetest 0.4.11 stable or later
Depends default
Licenses: Code WTFPL
Use in a singlenode mapgen world.
A very simple demonstration of how to create multiple levels of floatlands (y = 512 and up), a surface realm, and a lava underworld (y = -512) by using a 3D noise mapgen with a carefully manipulated density gradient.
You may spawn underground so disable damage before starting a world, then enable freemove and switch 'noclip' if necessary to fly up or down to the 3 realms.
In my 'flexrealm' mod the density gradient 'grad' was varied in 3D space to create spherical and cubic planets, dyson spheres, dyson cubes, tubeworlds, inverted and vertical realms. So the potential of this mapgen method is huge, the method is essentially to always calculate a density for each node:
Density = 3DdensityNoise + densityGradient
Then place stone when density > 0.
Most of my mapgens including watershed and riverdev are of this form so they could have the possibilities of this mod and flexrealm with minimal editing.
Density gradient is actually a 3D density field, 'field' being a scientific term meaning every point in 3D space has a value. In this mod the density field is only varied with y so it's called a 'gradient', in flexrealm it varies in all 3 dimensions.
For a good explanation of 3D noise mapgen (such as mgv5), see the article that was my introduction to lua mapgen, written by guess who http://c55.me/random/2011-07/noisestuff/
0.2.1
Added lux ore in underworld.
0.2.3
Towers to the floatlands. Grass, sand. Overgeneration and stability table system.
0.2.4
Added dirt nodes and surface detection that places a single layer of grass nodes.
0.2.6
Bugfixes.
^ Development screenshot
