Actions

Custom actions are registered in startup_scripts/ and invoked from Origins JSON data files.

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Registration Methods

Method	Callback Signature	JSON Type
registerEntityAction(id, cb)	(Entity, JsonObject) => void	origins_js:js_entity_action
registerBlockAction(id, cb)	(Level, BlockPos, Direction?, JsonObject) => void	origins_js:js_block_action
registerItemAction(id, cb)	(Level, Entity?, SlotAccess?, JsonObject) => void	origins_js:js_item_action
registerBiEntityAction(id, cb)	(Entity, Entity, JsonObject) => void	origins_js:js_bientity_action

The id must match between the JavaScript registration and the JSON data.

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JSON Format

Every action type uses the same JSON structure:

{
    "type": "origins_js:js_entity_action",
    "id": "my_action_id",
    "params": { "key": "value" }
}

• type — must be one of the values in the table above
• id — matches the first argument of register*
• params — optional JsonObject passed to the callback

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Entity Action

OriginsJS.registerEntityAction("heal_half", (entity, params) => {
    if (entity.isLiving()) entity.heal(entity.getMaxHealth() / 2);
});

{
    "type": "origins:action_on_callback",
    "entity_action_gained": {
        "type": "origins_js:js_entity_action",
        "id": "heal_half"
    }
}

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Block Action

OriginsJS.registerBlockAction("set_air", (world, pos, direction, params) => {
    world.setBlock(pos, Blocks.AIR.defaultBlockState(), 3);
});

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Item Action

OriginsJS.registerItemAction("damage_item", (world, entity, slotAccess, params) => {
    if (slotAccess != null) {
        slotAccess.get().hurt(1, world.random, null);
    }
});

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Bi-entity Action

OriginsJS.registerBiEntityAction("copy_effects", (actor, target, params) => {
    if (actor.isLiving() && target.isLiving()) {
        actor.getActiveEffects().forEach(effect => {
            target.addEffect(new net.minecraft.world.effect.MobEffectInstance(effect));
        });
    }
});