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Conduit

Prefab bindings

PrefabBindings is the parameter scope used during instantiation. Three sources combine, later overriding earlier: the prefab’s declared default params, instantiation-time overrides passed by the caller, and any sub-prefab rebindings. Coordinate expressions in the JSON ("@xMin", "@yFloor + 1") resolve against this map at instantiation, so one prefab template parameterises across dozens of call sites.

When to use it

Section titled “When to use it”
  • You’re calling Scene.instantiate and need to supply or override parameters.
  • You’re composing prefabs and want a sub-prefab to inherit + override the parent’s params.
  • You’re authoring a tool that introspects a prefab’s required params before instantiating it.

API

Section titled “API”
package me.zlex.conduit.prefab;


public final class PrefabBindings {
    public static PrefabBindings empty();
    public static PrefabBindings of(Map<String, Integer> values);


    public PrefabBindings put(String name, int value);
    public PrefabBindings putAll(Map<String, Integer> values);


    public int requireInt(String name);   // throws if missing
    public boolean has(String name);


    public Map<String, Integer> asMap();
    public PrefabBindings copy();
}

requireInt throws a clear error listing every known param, so missing-binding bugs surface immediately at instantiation rather than as silent zero-fill.

Example

Section titled “Example”
import me.zlex.conduit.prefab.Prefab;
import me.zlex.conduit.prefab.PrefabBindings;
import me.zlex.conduit.prefab.Scene;
import me.zlex.conduit.prefab.SceneStore;


public final class StagingBoxAt {


    public static Scene build(net.minecraft.server.level.ServerLevel level,
                              int cx, int cz, int half, int height) {
        Prefab.Id id = Prefab.Id.of("conduit", "default-staging-box");
        Prefab prefab = SceneStore.prefab(id);


        PrefabBindings bindings = PrefabBindings.empty()
                .putAll(prefab.params())                       // prefab defaults
                .put("xMin", cx - half).put("xMax", cx + half) // call-site overrides
                .put("zMin", cz - half).put("zMax", cz + half)
                .put("yFloor", 100).put("yCeiling", 100 + height);


        return Scene.instantiate(level, new net.minecraft.core.BlockPos(0, 0, 0),
                                 bindings, id, prefab, SceneStore.get());
    }
}

Notes

Section titled “Notes”
  • The combine order matters — load prefab defaults first, then layer overrides. putAll is just a shorthand for a sequence of puts.
  • A typo in a param name throws on the first element that references it — the error message lists the known keys, so the fix is usually obvious.
  • Sub-prefab references can rebind a subset; the rest fall through from the parent’s bindings.
Section titled “Related”