AdjacentRecipe

What is AdjacentRecipe

AdjacentRecipe sits between a fully shaped recipe and a fully shapeless recipe.

Like a shapeless recipe, items may be placed anywhere in the crafting grid with no fixed positional constraints. Unlike a shapeless recipe, the directions in which neighbouring items may appear are restricted by RelationType:

• CROSS — No item may have a diagonally adjacent neighbour (↖ ↗ ↙ ↘ are forbidden).
• DIAGONAL — No item may have a cross-adjacent neighbour (↑ ↓ ← → are forbidden).
• BOTH — All eight surrounding directions are permitted; no directional constraint is applied.

Every item must have at least one neighbour within distance 1. Placements where any item is isolated (distance ≥ 2 from all others) do not match.

Note

AdjacentRecipe only supports CRecipe.Type.SHAPELESS.

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Static Methods

checker(relationType: AdjacentRecipe.RelationType): CRecipePredicate

Returns the core CRecipePredicate that enforces the directional constraint for the given relationType.

This predicate is added to the recipe automatically during construction. You do not normally need to call it directly.

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Constructor

class AdjacentRecipe @JvmOverloads constructor(
    override val name: String,
    matters: List<CMatter>,
    val relationType: RelationType = RelationType.BOTH,
    customPredicates: List<CRecipePredicate>? = null,
    override val results: List<ResultSupplier>? = null
) : CRecipe

Parameter	Default	Description
name	—	Unique identifier for the recipe
matters	—	List of ingredients; placement order within the grid is unconstrained
relationType	BOTH	Adjacency rule applied to every placed item
customPredicates	null	Additional predicates evaluated before the adjacency check
results	null	List of ResultSupplier instances that produce the craft output

The adjacency predicate (checker(relationType)) is always appended to predicates automatically.

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AdjacentRecipe.RelationType

Defines which neighbouring directions are permitted between placed items.

Value	Forbidden directions	Permitted directions
CROSS	↖ ↗ ↙ ↘ (diagonal)	↑ ↓ ← → (cross)
DIAGONAL	↑ ↓ ← → (cross)	↖ ↗ ↙ ↘ (diagonal)
BOTH	— (none)	All 8 directions

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Usage Examples

In the diagrams below, # represents a placed item and _ represents an empty slot (excerpt from the top-left of a 6×6 grid).

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CROSS

Items must not have any diagonally adjacent neighbour (↖ ↗ ↙ ↘).

Matching placements

val recipe = AdjacentRecipe(
    name        = "cross_line",
    matters     = listOf(
        CMatterImpl.of(Material.STONE),
        CMatterImpl.of(Material.STONE),
        CMatterImpl.of(Material.STONE),
    ),
    relationType = AdjacentRecipe.RelationType.CROSS,
)

# # # _    ← horizontal line; items are only left/right adjacent, no diagonal neighbours → matches
_ _ _ _
_ _ _ _

# _ _ _
# _ _ _    ← vertical line; items are only up/down adjacent → matches
# _ _ _

Non-matching placements

# _ _ _    ← (0,0) and (1,1) are diagonally adjacent
# # _ _    ← the L-shape corner creates a diagonal pair → forbidden for CROSS → no match
_ _ _ _

# _ _ _    ← (0,0) and (1,1): diagonal pair, even with only 2 items → no match
_ # _ _
_ _ _ _

---

DIAGONAL

Items must not have any cross-adjacent neighbour (↑ ↓ ← →).

Matching placements

val recipe = AdjacentRecipe(
    name        = "diagonal_line",
    matters     = listOf(
        CMatterImpl.of(Material.STONE),
        CMatterImpl.of(Material.STONE),
        CMatterImpl.of(Material.STONE),
    ),
    relationType = AdjacentRecipe.RelationType.DIAGONAL,
)

# _ _ _    ← diagonal line going down-right; items are only diagonally adjacent → matches
_ # _ _
_ _ # _

_ _ # _    ← diagonal line going down-left → matches
_ # _ _
# _ _ _

Non-matching placements

# # _ _    ← (0,0) and (1,0) are cross-adjacent (left/right) → forbidden for DIAGONAL → no match
_ _ _ _
_ _ _ _

# _ _ _    ← (0,0)–(1,1) is diagonal (OK), but (1,1)–(2,1) is cross-adjacent → no match
_ # # _
_ _ _ _

---

BOTH

All 8 surrounding directions are permitted; no directional constraint is applied. However, every item must still have at least one neighbour at distance 1.

Matching placements

val recipe = AdjacentRecipe(
    name        = "both_example",
    matters     = listOf(
        CMatterImpl.of(Material.STONE),
        CMatterImpl.of(Material.STONE),
    ),
    relationType = AdjacentRecipe.RelationType.BOTH,
)

# # _ _    ← cross-adjacent → matches
_ _ _ _

# _ _ _    ← diagonally adjacent → matches
_ # _ _

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Maximum Item Count

The table below shows the maximum number of items that can be placed in a 6×6 grid for each RelationType.

RelationType	Maximum	Example pattern
CROSS	18	Fill all rows in even-numbered columns (x = 0, 2, 4)
DIAGONAL	18	Fill cells where both x and y are even, or both are odd
BOTH	36	No constraint — all 36 cells are valid

If matters exceeds this limit and isValidRecipe() is called, an error is returned together with a visual placement pattern for reference.