A template pool is a group of structure pieces of jigsaw structures. A structure piece is a structure template, a placed feature, or a combination of multiple other pieces. During generation, pieces are randomly selected from the pool. Template pools are configured using JSON files stored within a data pack in the folder data/<namespace>/worldgen/template_pool or a addon at <root BP>/worldgen/template_pools.
Java Edition:
- [NBT Compound / JSON Object] The root tag.
- [String] fallback: One (an [String] ID) — Used for terminating pieces (such as the end of a village road) or as fallback if structures in this pool can't generate. (Note that empty pool elements don't trigger this, they just generate nothing.)
- [NBT List / JSON Array] elements: A list of elements to randomly select from.
- [NBT Compound / JSON Object]: An element.
- [Int] weight: How likely this element is to be chosen when using this pool. Value between 1 and 150 (inclusive).
- [NBT Compound / JSON Object] element: A pool element.
- [String] element_type: The type of the pool element. See Template pool § Pool elements.
- [String] projection: Can be
rigid to place a fixed structure (like a house), or terrain_matching to match the terrain height (like a village road).
- Additional fields depending on [String] element_type. See Template pool § Pool elements.
Bedrock Edition:
- [NBT Compound / JSON Object] The root tag.
- [String] format_version: [more information needed]
- [NBT Compound / JSON Object] minecraft:template_pool
- [NBT Compound / JSON Object] description
- [String] identifier: The identifier used for this template pool.
- [String] fallback: One (an [String] ID) — Used for terminating pieces (such as the end of a village road) or as fallback if structures in this pool can't generate. (Note that empty pool elements don't trigger this, they just generate nothing.)
- [NBT List / JSON Array] elements: A list of elements to randomly select from.
- [NBT Compound / JSON Object]: An element.
- [Int] weight: How likely this element is to be chosen when using this pool. Value between 1 and 150 (inclusive).
- [NBT Compound / JSON Object] element: A pool element.
- [String] element_type: The type of the pool element. See Template pool § Pool elements.
- [String] projection: Can be
rigid to place a fixed structure (like a house), or terrain_matching to match the terrain height (like a village road).
- Additional fields depending on [String] element_type. See Template pool § Pool elements.
A pool element represents a single piece of a jigsaw structure.
This piece places a single structure template. The jigsaw blocks in the template are used for connections and the size of the template determines the bounding box of the piece. The template gets processed using a processor list.
- [NBT Compound / JSON Object]: The element
- [String] element_type:
minecraft:single_pool_element
- [String] projection: See above.
- [String] location: One structure template (an [String] ID) — The template to place
- [String][NBT Compound / JSON Object][NBT List / JSON Array] processors: One processor list (an [String] ID, or a new [NBT Compound / JSON Object][NBT List / JSON Array] processor list definition) — The processors that should modify the template.
- [String] override_liquid_settings[JE only]: Overrides the
liquid_settings value in structure definition for this particular element. See Jigsaw_structure#Data_values.
[more information needed]
This is a legacy version of the single pool element that doesn't place any air blocks in the template, instead keeping the original block of the world.
- [NBT Compound / JSON Object]: The element
- [String] element_type:
minecraft:legacy_single_pool_element
- [String] projection: See above.
- [String] location: One structure template (an [String] ID) — The template to place
- [String][NBT Compound / JSON Object][NBT List / JSON Array] processors: One processor list (an [String] ID, or a new [NBT Compound / JSON Object][NBT List / JSON Array] processor list definition) — The processors that should modify the template.
This piece places a placed feature. The bounding box of the piece is 1×1×1 blocks. The piece gets connected to its parent piece as if it had a jigsaw block that faces downwards with the name minecraft:bottom[JE only]. In bedrock the name can be anything and no target name is required for the parent jigsaw block.
Feature will always attempt to spawn if jigsaw joint is set to rollable. If joint is set to aligned, then a feature will attempth to spawn only when structure rotation upon generation is corresponding to jigsaw orientation in next cases: 0°=up_south, 90°=up_east, 180°=up_north, 270°=up_west.
- [NBT Compound / JSON Object]: The element
- [String] element_type:
minecraft:feature_pool_element
- [String] projection: See above.
- [String] feature: One placed feature (an [String] ID, or a new [NBT Compound / JSON Object] placed feature definition) — The feature to place.
This piece places multiple pool elements in sequence. The first element is connected using a jigsaw block, further elements are placed with their starting point at (0,0,0) of the bounding box of the first element using the same rotation. If an element fails to generate, then it and all further elements are discarded. The bounding box of the piece is the smallest box that contains all element bounding boxes. This piece cannot generate any further child pieces.
- [NBT Compound / JSON Object]: The element
- [String] element_type:
minecraft:list_pool_element
- [String] projection: See above.
- [NBT List / JSON Array] elements: A list of elements to choose from.
- [NBT Compound / JSON Object]: A pool element.
This piece doesn't place anything.
- [NBT Compound / JSON Object]: The element
- [String] element_type:
minecraft:empty_pool_element
- [String] projection: See above. [JE only]
