To install my mod, build the source code at:

zip package:

https://gitlab.com/h2mm/minetest/-/arch ... inbrot.zip
GitLab branch:

https://gitlab.com/h2mm/minetest/tree/terrainbrot.

After that you can see the "terrainbrot" as one option. Windows users can download the (currently outdated) build

here.

Warning! The settings are currently subject of change. If you download a new version of terrainbrot, reset the settings to default.
This mapgen is based on the "fractal" mapgen. It iterates a rational function and uses perlin noise to generate stuff endlessly. Its variety is very huge. It can generate anything from flat lands to insane mountains. It also generates rivers. Some areas are full of rivers, other areas contain no rivers at all. Some rivers are straight, other rivers are curly.

It is not supposed to be a realistic terrain. I focused that on being simple and using a lot of variety. However, there are many places those look very realistic. I think, it might be also a good fantasy world.

Some

screenshots: https://imgur.com/a/HSv5oCN
A short explanation of how it works:

Terrainbrot is an iterative complex number fractal like the Mandelbrot set. The formula is z -> R1(z) + R2(c) where R1 and R2 are rational functions. The default settings use rational functions of rank 10. The complex number z is created from the X- and Z-coordinates, but how does it involve the Y-coordinate? In each step, the travelled distance is calculated. After that, the number z is scaled according to the travelled distance and the Y-coordinate. I tried also other ways of involving the Y-coordinate and this one seems the best.

This makes quite good terrain but it's still more or less limited to the unit disc because the farther points always diverge. The complex number z is generated by two perlin noises. They have the same parameters, only the seed is different. And that's not all. The coeficients of the rational functions are also generated by perlin noises. In the default settings, the rank of these rational functions is 10. The rank of the polynoms on the top is 10, the rank of the polynoms on the bottom is 8. The upper polynoms have 11 coeficients, the lower polynoms have 9 coeficients. Each coeficient has both real and imaginary part. There are totally 80 parameters and one perlin noise for each. Again, the noise parameters are the same, just the seed is different.

Rivers are generated by escape-angle. If the point hits the correct angle in its last iteration and is in the correct distance, it is a river point. There are some minor tweaks to prevent the rivers from flowing out of its banks but it still happens sometimes.

All screenshots are from one world. The seed is no longer valid but the look hasn't changed. It's hard to find a world in which all interesting stuff can be seen. I have found at least some of them in this world.

License LGPLv2.1+

Changelog:

2018-06-21 Initial version

2018-07-16 Improved speed

2018-07-19 Added Cavebrot

2018-09-03 Fixed spawnpoint bug

Video: https://youtu.be/XireVf2cwOM
If you lack the reality, go on a trip or find a job.