Structure Spawn Loader

This mod provides the ability for datapacks and other modifications to use JSON files to add mob spawning to creature generation lists for various structures.

Basic Operating Principle

When a structure contains at least one mob spawn entry (added by the game itself, another mod, or through this utility), then within the bounds of that structure for the corresponding creature category (monsters, animals, ambient, etc.), the structure's spawn list will be used instead of the biome's standard spawn list.

JSON File Format

JSON files with spawn settings should be located at the path: data/namespace/structure_spawn_loader/path.json

Each file must contain two mandatory fields:

• "structure" - structure type identifier
• "spawner" - object with spawn parameters

Files missing these fields will be ignored, allowing to disable entries from other mods or datapacks by overriding them with an empty object {}.

Spawner Parameters

In the "spawner" object, the following settings are available:

• "type" - creature type identifier for spawning
• "weight" - relative weight of this entry compared to others (common monsters have a weight of 100)
• "minCount" and "maxCount" - determine the size of the spawning creature group (most mobs use 4-4, endermen 1-4, witches and zombie villagers 1-1)

Naming Recommendations

For convenience, the following naming scheme is recommended:

• namespace - mod or datapack identifier
• path - structuremod/structure/entitymod/entity for adding creature entitymod:entity to structure structuremod:structure

Usage Example

File: data/examplemod/structure_spawn_loader/minecraft/village/minecraft/evoker.json

Developer Support

Mod developers can use this library through Cursemaven in their development environment. A data provider for generating spawn JSON files is also provided.