Controllers

Controllers are the machine brains. A placed controller checks the blocks around itself, forms a matching structure, and runs process recipes for that structure.

How controllers work

The controller uses its world position as the origin.
It scans known structures that reference that controller ID.
If the blocks around it match a structure layout, the controller becomes formed.
Once formed, it checks matching process recipes.
A recipe can run when all inputs exist, all outputs have room, and all conditions pass.

The controller GUI reports whether a structure is formed and which structure was detected.

Creating a controller

Create JSON files in:

config/mm/controllers/

Minimal example:

{
  "type": "mm:machine",
  "id": "my_controller",
  "name": "My Controller"
}

Field	Meaning
`type`	Controller type. For normal machines use `mm:machine`.
`id`	Unique controller path. `my_controller` becomes the generated controller block/item id `mm:my_controller`.
`name`	Default English display name. Translation key: `block.mm.<id>`.

Parallel-processing fields

Controllers can define default parallel-processing behaviour:

{
  "type": "mm:machine",
  "id": "my_controller",
  "name": "My Controller",
  "parallelProcessingDefault": false,
  "maxParallelRecipes": -1,
  "recipeSelectionMode": "default"
}

Field	Default	Meaning
`parallelProcessingDefault`	`false`	Whether recipes for this controller run in parallel by default.
`maxParallelRecipes`	`-1`	Controller-level parallel cap. `-1` means use the global config value. Non-negative values are capped internally at `100`.
`recipeSelectionMode`	`default`	Recipe scheduling mode used when multiple recipes are runnable. See below.

Recipe selection mode

Controllers normally scan matching recipes in their existing order. For machines with many recipes that share one port, such as sieves, a fairer selection mode can stop one input type from dominating the machine.

{
  "type": "mm:machine",
  "id": "big_sieve",
  "name": "Big Sieve",
  "recipeSelectionMode": "round_robin_input_item"
}

Mode	Meaning
`default`	Current/default behavior. Recipes are checked in the normal rotating scan order.
`avoid_same_recipe`	Prefer not to start the exact same recipe twice in a row when another runnable recipe exists.
`round_robin_input_item`	Prefer the least-recently-used consumed item input among currently runnable recipes. Useful for machines where gravel/sand/dust-style inputs should be kept balanced.

round_robin_input_item falls back to any runnable recipe if only one input type is available, so it should not stall a machine just because the next preferred input is missing.

ID usage

The generated controller block id is exactly mm:<id>. For example, id: "my_controller" generates mm:my_controller, not mm:my_controller_controller.

When another file references this controller, use the full ID:

"controllerIds": "mm:my_controller"

or:

"controllerIds": ["mm:my_controller", "mm:another_controller"]