Combined machine recipes (experimental)

MachineRecipeSpec describes positional item/fluid inputs and outputs, a recipe type ID, and processing ticks. Each section is limited to 16 entries. Recipes require an input and an output, with duration 1..1,728,000 ticks. Lists are immutable. FluidIngredient accepts an exact fluid ID or a fluid tag and a positive amount. Quantities use SDK units: 81,000 units per bucket, not millibuckets.

MachineFluidPlan checks immutable tank snapshots without consuming anything. It returns missing-input, output-blocked, or ready with proposed replacement tanks. Inputs and outputs map to separate positional tanks. Tags are resolved by the owning runtime's supplied predicate. Existing output fluids cannot be mixed, and capacity checks avoid integer overflow. A blocked result retains the original tanks.

Registration

var type = context.recipes().registerMachineType("washing", 1);
context.workbenches().register("washer", WorkbenchSpec.builder("Washer", type)
    .persistentMachine(storage, List.of("coolant"), List.of("effluent"))
    .build(), craft -> { });

Register the persistent block first. Storage needs inputSlots + 1 inventory slots and all named tanks. The current menu supports 1–5 positional item inputs and one stored item output; each fluid section supports up to 16 positional tanks. Input and output tanks must be distinct. Larger item layouts permitted by the general recipe record are rejected by this loader and generator.

Data-pack format

Files live at data/<namespace>/enderfall_machine/<path>.json on every target. This is an SDK data-pack loader, not a vanilla crafting serializer or recipe-book entry. Higher-priority packs override the same resource; candidates are ordered by resource ID. DataGenerationContext.machineRecipe(id, spec) emits this format:

{
  "type": "example:washing",
  "duration_ticks": 60,
  "item_inputs": [{"item": "minecraft:amethyst_shard", "count": 1}],
  "fluid_inputs": [{"fluid": "minecraft:water", "amount": 81000}],
  "item_outputs": [{"item": "minecraft:prismarine_crystals", "count": 1}],
  "fluid_outputs": [{"fluid": "minecraft:water", "amount": 40500}]
}

Use tag instead of item or fluid for native tag matching. All four arrays are required, even empty fluid sections. One bucket is 81,000 SDK units (1,000 mB). Recipe layouts must match the machine's item and tank counts to be selected. Resources are limited to 64 KiB, nesting to 12, and discovery to 4,096 recipes. Invalid resources are logged and excluded. Recipes are cached per resource manager; replacing it on data-pack reload reloads the definitions. A changed definition hash or duration resets progress.

Processing

The timed processor validates items, remainders, fluid identity and output capacity before completion. Blocked outputs pause without consuming ingredients. Completion commits item, field and tank replacements together, then notifies viewers. Retained tank handles remain valid. Ingredients stay available to automation while working; removing them cancels progress. No offline catch-up or reservation occurs.

The first matching recipe wins even if blocked. Input slots need room for crafting remainders. Custom item components, chance outputs, shared input/output tanks and recipe-book integration are outside this feature. Real gameplay checks are still required for save/reopen, reload, blocked outputs and automation races.