I want to generate a completely new world that is not like the standard one.

Edited March 23, 20205 yr by GreatWolf

For 1.15? I doubt there's any tutorials of world generation yet since 1.15 is relatively new. You should take a look at how vanilla minecraft does it. 

1 hour ago, GreatWolf said:

I want to generate a completely new world that is not like the standard one.

@GreatWolf, what do you mean with world, a new dimension or a biome? For a Biome see this: 

 

Else see my or TurtyWurty‘s github.

2 hours ago, DragonITA said:

@GreatWolf , что ты имеешь в виду под миром, новым измерением или биомом? Для биома см. Это: 

 

Еще посмотрите мой или TurtyWurty's Github .

 

Creating a completely new world without standard biomes. For example, create greenery after an atomic strike (that is, generate a world with new blocks and possibly buildings)

7 hours ago, GreatWolf said:

 

Creating a completely new world without standard biomes. For example, create greenery after an atomic strike (that is, generate a world with new blocks and possibly buildings)

You need then Dimension, else a new World would be too complicated. Yes, you can make a custom Dimension with custom Biomes. If you want to make a World in the Space for example the world would be limited. I am sure that mods such Spacecraft and etc use Dimensions with custom Biomes, for making so that you think it was a new world. If you want to make mini planets in the sky or space, then this is more structure and others thing.

7 hours ago, GreatWolf said:

For example, create greenery after an atomic strike (that is, generate a world with new blocks and possibly buildings)

I not thin this is possible, but you can or teleport the player in this Dimension and then say it was a new World, or try to replace all structures, blocks, mobs, dimensions and biomes with your, but this was the same as reload the entire game, so let‘s say you go into the world, after 15 min (not for me, but here are players that it was so) you want to play minecraft, but then you re-need to wait, but this time 25 min (depends on what you want to add in your new Dimension). This is what i mean, if it was false so say it me.

I think what you may be looking for is a new WorldType.

If I were looking, I'd start by looking at the net.minecraft.world.WorldType class.