Processor Conditions - Lithostitched

Processor conditions provide conditional logic for structure processing, allowing processors to execute only when certain conditions are met. They are used primarily with the Condition Processor.

Condition Interface

All processor conditions implement the ProcessorCondition interface:

public interface ProcessorCondition {
    boolean test(
        WorldGenLevel level,
        Data data,
        StructurePlaceSettings settings,
        RandomSource random
    );
    
    record Data(
        BlockPos pos,           // Structure placement position
        BlockPos pivot,         // Structure pivot point
        StructureBlockInfo relative,  // Block in template coordinates
        StructureBlockInfo absolute   // Block in world coordinates
    ) {}
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.ProcessorCondition:1

All Of

Returns true only if all child conditions return true.

Type ID

lithostitched:all_of

Java Interface

public record AllOf(List<ProcessorCondition> conditions) 
    implements ProcessorCondition {
    
    @Override
    public boolean test(WorldGenLevel level, Data data, 
                       StructurePlaceSettings settings, RandomSource random);
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.AllOf:1

JSON Format

{
  "type": "lithostitched:all_of",
  "conditions": [
    {
      "type": "lithostitched:random_chance",
      "chance": 0.5
    },
    {
      "type": "lithostitched:matching_blocks",
      "blocks": "#minecraft:planks",
      "match_type": "input"
    }
  ]
}

Fields

conditions

array

required

List of conditions that must all be true

Behavior

Evaluates conditions in order
Short-circuits on first false result (remaining conditions are not tested)
Returns true if all conditions return true
Returns true if the list is empty

Example

{
  "type": "lithostitched:all_of",
  "conditions": [
    {
      "type": "lithostitched:random_chance",
      "chance": 0.3
    },
    {
      "type": "lithostitched:matching_blocks",
      "blocks": ["minecraft:stone"],
      "match_type": "location"
    }
  ]
}

Only proceeds if random chance passes AND the block at the location is stone.

Any Of

Returns true if at least one child condition returns true.

Type ID

lithostitched:any_of

Java Interface

public record AnyOf(List<ProcessorCondition> conditions) 
    implements ProcessorCondition {
    
    @Override
    public boolean test(WorldGenLevel level, Data data,
                       StructurePlaceSettings settings, RandomSource random);
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.AnyOf:1

JSON Format

{
  "type": "lithostitched:any_of",
  "conditions": [
    {
      "type": "lithostitched:matching_blocks",
      "blocks": ["minecraft:dirt"],
      "match_type": "location"
    },
    {
      "type": "lithostitched:matching_blocks",
      "blocks": ["minecraft:grass_block"],
      "match_type": "location"
    }
  ]
}

Fields

conditions

array

required

List of conditions where at least one must be true

Behavior

Evaluates conditions in order
Short-circuits on first true result (remaining conditions are not tested)
Returns true if any condition returns true
Returns false if the list is empty

Example

{
  "type": "lithostitched:any_of",
  "conditions": [
    {
      "type": "lithostitched:matching_blocks",
      "blocks": "#minecraft:logs",
      "match_type": "input"
    },
    {
      "type": "lithostitched:matching_blocks",
      "blocks": "#minecraft:planks",
      "match_type": "input"
    }
  ]
}

Matches if the input block is either a log or planks.

Matching Blocks

Tests if a block matches a set of blocks and optional state properties.

Type ID

lithostitched:matching_blocks

Java Interface

public record MatchingBlocks(
    HolderSet<Block> blocks,
    StatePropertiesPredicate properties,
    BlockType matchType
) implements ProcessorCondition {
    
    @Override
    public boolean test(WorldGenLevel level, Data data,
                       StructurePlaceSettings settings, RandomSource random);
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.MatchingBlocks:1

JSON Format

{
  "type": "lithostitched:matching_blocks",
  "blocks": "#minecraft:planks",
  "properties": {
    "conditions": [
      {
        "name": "waterlogged",
        "values": ["true"]
      }
    ]
  },
  "match_type": "input"
}

Fields

blocks

string | array

required

Block tag (prefixed with #) or list of block IDs to match against

properties

StatePropertiesPredicate

default:"{}"

Optional state property requirements. Uses Minecraft’s StatePropertiesPredicate format.

match_type

string

default:"input"

Which block to test:

input - The block from the structure template (relative coordinates)
location - The block currently at the world location (absolute coordinates)

Block Type Enum

public enum BlockType {
    INPUT("input", data -> data.relative().state()),
    LOCATION("location", data -> data.absolute().state());
}

Source: dev.worldgen.lithostitched.worldgen.processor.enums.BlockType:1

Behavior

Tests if the specified block matches the block set
Optionally tests block state properties
Can test either the template block or the world block

Examples

Simple Block Match

{
  "type": "lithostitched:matching_blocks",
  "blocks": ["minecraft:oak_planks", "minecraft:spruce_planks"],
  "match_type": "input"
}

Tag Match with Properties

{
  "type": "lithostitched:matching_blocks",
  "blocks": "#minecraft:stairs",
  "properties": {
    "conditions": [
      {
        "name": "facing",
        "values": ["north", "south"]
      }
    ]
  },
  "match_type": "input"
}

World Block Match

{
  "type": "lithostitched:matching_blocks",
  "blocks": ["minecraft:water"],
  "match_type": "location"
}

Checks if there’s water at the placement location in the world.

Not

Inverts the result of a child condition.

Type ID

lithostitched:not

Java Interface

public record Not(ProcessorCondition condition) 
    implements ProcessorCondition {
    
    @Override
    public boolean test(WorldGenLevel level, Data data,
                       StructurePlaceSettings settings, RandomSource random);
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.Not:1

JSON Format

{
  "type": "lithostitched:not",
  "condition": {
    "type": "lithostitched:random_chance",
    "chance": 0.3
  }
}

Fields

condition

ProcessorCondition

required

The condition to invert

Behavior

Returns true if the child condition returns false
Returns false if the child condition returns true

Example

{
  "type": "lithostitched:not",
  "condition": {
    "type": "lithostitched:matching_blocks",
    "blocks": "#minecraft:air",
    "match_type": "location"
  }
}

Returns true if the location is NOT air.

Position

Tests block position using Minecraft’s position rule tests.

Type ID

lithostitched:position

Java Interface

public record Position(PosRuleTest predicate, PosAnchor anchor) 
    implements ProcessorCondition {
    
    @Override
    public boolean test(WorldGenLevel level, Data data,
                       StructurePlaceSettings settings, RandomSource random);
    
    public enum PosAnchor {
        STRUCTURE_START,  // Relative to structure origin
        PIECE             // Relative to piece origin
    }
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.Position:1

JSON Format

{
  "type": "lithostitched:position",
  "predicate": {
    "type": "minecraft:axis_aligned_linear_pos",
    "axis": "y",
    "min_dist": 0,
    "max_dist": 5
  },
  "anchor": "structure_start"
}

Fields

predicate

PosRuleTest

required

Minecraft position rule test. Common types:

minecraft:axis_aligned_linear_pos - Tests distance along an axis
minecraft:linear_pos - Tests linear distance from anchor

anchor

string

default:"structure_start"

Position anchor point:

structure_start - Tests relative to structure origin
piece - Tests relative to piece origin

Behavior

Uses Minecraft’s PosRuleTest system
Tests block positions relative to an anchor point
Useful for applying effects only in certain areas of a structure

Examples

Height Range

{
  "type": "lithostitched:position",
  "predicate": {
    "type": "minecraft:axis_aligned_linear_pos",
    "axis": "y",
    "min_dist": 0,
    "max_dist": 10
  },
  "anchor": "structure_start"
}

Matches blocks within 10 blocks vertically from structure start.

Radial Distance

{
  "type": "lithostitched:position",
  "predicate": {
    "type": "minecraft:linear_pos",
    "min_dist": 5,
    "max_dist": 15
  },
  "anchor": "piece"
}

Matches blocks 5-15 blocks from the piece origin.

Random Chance

Randomly passes with a specified probability.

Type ID

lithostitched:random_chance

Java Interface

public record RandomChance(float chance) 
    implements ProcessorCondition {
    
    @Override
    public boolean test(WorldGenLevel level, Data data,
                       StructurePlaceSettings settings, RandomSource random);
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.RandomChance:1

JSON Format

{
  "type": "lithostitched:random_chance",
  "chance": 0.3
}

Fields

chance

float

required

Probability of passing (0.0 to 1.0). 0.0 = never, 1.0 = always.

Behavior

Generates a random float between 0 and 1
Returns true if the random value is less than chance
Uses the RandomSource provided to the test method

Examples

50% Chance

{
  "type": "lithostitched:random_chance",
  "chance": 0.5
}

10% Chance

{
  "type": "lithostitched:random_chance",
  "chance": 0.1
}

True

Always returns true.

Type ID

lithostitched:true

Java Interface

public record True() implements ProcessorCondition {
    @Override
    public boolean test(WorldGenLevel level, Data data,
                       StructurePlaceSettings settings, RandomSource random);
}

Source: dev.worldgen.lithostitched.worldgen.processor.condition.True:1

JSON Format

{
  "type": "lithostitched:true"
}

Behavior

Always returns true
Useful as a placeholder or default condition
Can be used to unconditionally execute a processor branch

List Shorthand

Processor conditions support a shorthand syntax where a list of conditions is automatically wrapped in all_of:

[
  {
    "type": "lithostitched:random_chance",
    "chance": 0.5
  },
  {
    "type": "lithostitched:matching_blocks",
    "blocks": "#minecraft:planks"
  }
]

This is equivalent to:

{
  "type": "lithostitched:all_of",
  "conditions": [
    {
      "type": "lithostitched:random_chance",
      "chance": 0.5
    },
    {
      "type": "lithostitched:matching_blocks",
      "blocks": "#minecraft:planks"
    }
  ]
}

Source: ProcessorCondition.java:24

Usage with Condition Processor

Processor conditions are primarily used with the Condition Processor:

{
  "processor_type": "lithostitched:condition",
  "random_mode": {
    "mode": "per_block"
  },
  "if_true": {
    "type": "lithostitched:all_of",
    "conditions": [
      {
        "type": "lithostitched:random_chance",
        "chance": 0.2
      },
      {
        "type": "lithostitched:matching_blocks",
        "blocks": "#minecraft:planks",
        "match_type": "input"
      }
    ]
  },
  "then": [
    {
      "processor_type": "minecraft:block_rot",
      "integrity": 0.5
    }
  ],
  "else": []
}

This applies block decay only to planks with a 20% chance.

Complex Condition Examples

Weathering Based on Height and Block Type

{
  "type": "lithostitched:all_of",
  "conditions": [
    {
      "type": "lithostitched:position",
      "predicate": {
        "type": "minecraft:axis_aligned_linear_pos",
        "axis": "y",
        "min_dist": 10,
        "max_dist": 999
      },
      "anchor": "structure_start"
    },
    {
      "type": "lithostitched:matching_blocks",
      "blocks": ["minecraft:copper_block"],
      "match_type": "input"
    },
    {
      "type": "lithostitched:random_chance",
      "chance": 0.7
    }
  ]
}

Either Condition with Exclusions

{
  "type": "lithostitched:all_of",
  "conditions": [
    {
      "type": "lithostitched:any_of",
      "conditions": [
        {
          "type": "lithostitched:matching_blocks",
          "blocks": "#minecraft:logs",
          "match_type": "input"
        },
        {
          "type": "lithostitched:matching_blocks",
          "blocks": "#minecraft:planks",
          "match_type": "input"
        }
      ]
    },
    {
      "type": "lithostitched:not",
      "condition": {
        "type": "lithostitched:matching_blocks",
        "blocks": ["minecraft:water"],
        "match_type": "location"
      }
    }
  ]
}

Matches logs or planks, but only if there’s no water at the location.

Registration

Processor conditions are registered in Lithostitched.java:197-205:

public static void registerCommonProcessorConditions(
    BiConsumer<String, MapCodec<? extends ProcessorCondition>> consumer
) {
    consumer.accept("all_of", AllOf.CODEC);
    consumer.accept("any_of", AnyOf.CODEC);
    consumer.accept("matching_blocks", MatchingBlocks.CODEC);
    consumer.accept("not", Not.CODEC);
    consumer.accept("position", Position.CODEC);
    consumer.accept("random_chance", RandomChance.CODEC);
    consumer.accept("true", True.CODEC);
}

Worldgen Modifiers

Structures & Templates

Surface & Terrain

Features & Placement

Blocks & State

​Condition Interface

​All Of

​Type ID

​Java Interface

​JSON Format

​Fields

​Behavior

​Example

​Any Of

​Type ID

​Java Interface

​JSON Format

​Fields

​Behavior

​Example

​Matching Blocks

​Type ID

​Java Interface

​JSON Format

​Fields

​Block Type Enum

​Behavior

​Examples

​Simple Block Match

​Tag Match with Properties

​World Block Match

​Not

​Type ID

​Java Interface

​JSON Format

​Fields

​Behavior

​Example

​Position

​Type ID

​Java Interface

​JSON Format

​Fields

​Behavior

​Examples

​Height Range

​Radial Distance

​Random Chance

​Type ID

​Java Interface

​JSON Format

​Fields

​Behavior

​Examples

​50% Chance

​10% Chance

​True

​Type ID

​Java Interface

​JSON Format

​Behavior

​List Shorthand

​Usage with Condition Processor

​Complex Condition Examples

​Weathering Based on Height and Block Type

​Either Condition with Exclusions

​Registration

Build docs developers (and LLMs) love

Condition Interface

All Of

Type ID

Java Interface

JSON Format

Fields

Behavior

Example

Any Of

Type ID

Java Interface

JSON Format

Fields

Behavior

Example

Matching Blocks

Type ID

Java Interface

JSON Format

Fields

Block Type Enum

Behavior

Examples

Simple Block Match

Tag Match with Properties

World Block Match

Not

Type ID

Java Interface

JSON Format

Fields

Behavior

Example

Position

Type ID

Java Interface

JSON Format

Fields

Behavior

Examples

Height Range

Radial Distance

Random Chance

Type ID

Java Interface

JSON Format

Fields

Behavior

Examples

50% Chance

10% Chance

True

Type ID

Java Interface

JSON Format

Behavior

List Shorthand

Usage with Condition Processor

Complex Condition Examples

Weathering Based on Height and Block Type

Either Condition with Exclusions

Registration