Generator options GUI
The generator options GUI allows configuring how new chunks are generated in the downloaded world.
The world seed is used by Minecraft to generate new chunks. See the Minecraft Wiki page on the seed. Note that this only matters with new chunks - you can use the downloaded world for most things without the seed*.
You can either manually type the seed in this box if you know it (or a server operator tells you), or if you have permission, you can use the /seed command to get the seed, in which case it will automatically be entered into this text box.
*Slime chunks, used for spawning slimes, depend on the seed to work, so slime farms will not work without the seed.
To make use of the seed in the downloaded world, you'll need to change the world generator. By default, World Downloader uses a custom superflat preset that only generates air, so that new chunks will not have irrelevant terrain from the wrong seed. You can use the generator button to cycle between several generators:
- Leave empty
- Empty chunks are generated using a custom superflat preset.
- Default
- The normal world generator is used, with biomes and such.
- Superflat
- The superflat world generator is used - an infinite flat area for building on. You can configure the preset.
- Large biomes
- Like default, but with larger biomes
- AMPLIFIED
- Tall, chaotic world with large mountains.
- Custom
- The custom world type from Minecraft 1.8. You can change a lot of generator properties here (the configuration GUI is accessible).
- Legacy (1.1)
- Minecraft 1.1's world generator. To be honest, I'm not entirely sure what the difference is - perhaps it has something to do with 1.1's lower world height.
You can also chose whether or not structures are generated. This effects mineshafts, strongholds, and villages, among other things.