ZMJJKK123-hub Custom World Generation
This content applies only to Java Edition. This article covers datapack-controlled custom worlds (see "Custom" for JSON-driven worlds, and "Custom/Java Edition before 1.13" for legacy world types).
Custom world generation lets datapacks change how worlds generate.
World presets and dimensions
World presets and dimensions control which dimensions a world has. Every dimension defines its chunk generator (noise, debug, or flat); noise generators additionally define noise settings, biomes, and biome distribution. See the world preset definition format and dimension definition format.
Noise settings
Noise settings define the shapes of terrain and noise caves plus the blocks attached during terrain generation; used via the dimension's noise generator. See noise settings.
Density functions
Density functions provide coordinate-dependent values to the noise router of noise settings. See density functions.
Noise
Noise produces coordinate-dependent values, referenced by density functions or surface rules. See noise.
Biomes
Biomes are regions within a dimension with unique features, carvers, climate, mob spawning, ambience, and colors. See the biome definition format.
Carvers
Carvers carve caves and canyons. Note: noise caves come from noise settings, not carvers. See the carver definition format.
Features
Features are decorative block structures generated per chunk after terrain. See configured features and placed features.
Structures
Structures (structure features) generate structures; jigsaw structures offer extensive customization. See structure templates, structure definitions, structure sets, template pools, and processor lists.
Surface builders (removed)
Since 21w41a, surface blocks are controlled by noise settings. Surface builders were removed from Java Edition.