Placement Systems

Placement Systems

Placement systems control where structures spawn in the world. Moogs Structure Lib provides AdvancedRandomSpread, an enhanced version of Minecraft's random spread placement with additional features.

Overview

Moogs Structure Lib uses moogs_structures:advanced_random_spread as its primary placement type. It extends vanilla random spread with:

• Super exclusion zones
• Minimum distance from spawn
• Enhanced spacing control
• Frequency reduction methods

AdvancedRandomSpread

Required Fields

type

Type: String
Example: "moogs_structures:advanced_random_spread"

Must always be "moogs_structures:advanced_random_spread" for Moogs Structure Lib structures.

salt

Type: Integer
Example: 203698201

Unique identifier for this structure set. Affects which chunks are selected for structure placement. Each structure set should have a unique salt.

Tip: Use large random numbers. Avoid reusing salts across different structure sets.

spacing

Type: Integer (0 to Integer.MAX_VALUE)
Example: 34

Average number of chunks between structure attempts. Higher values mean rarer structures.

Important:

• Must be greater than separation
• Internally multiplied by 1.65 by Moogs Structure Lib
• 1 chunk = 16 blocks

Example: spacing: 34 means structures attempt to spawn approximately every 34 chunks (544 blocks), but internally becomes ~56 chunks (896 blocks).

separation

Type: Integer (0 to Integer.MAX_VALUE)
Example: 26

Minimum number of chunks between structures. Ensures structures don't spawn too close together.

Important:

• Must be less than spacing
• Internally multiplied by 1.65 by Moogs Structure Lib
• If spacing <= separation, structures cannot spawn properly!

Example: separation: 26 means structures must be at least 26 chunks (416 blocks) apart, internally ~43 chunks (688 blocks).

Optional Fields

locate_offset

Type: Vec3i (Array of 3 integers)
Example: [0, 0, 0] or [8, 0, 8]

Offset for the /locate command. Adjusts where the locate command points when finding this structure.

Default: [0, 0, 0]

Example:

{
  "locate_offset": [8, 0, 8]
}

This offsets the locate command by 8 blocks in X and Z.

frequency

Type: Float (0.0 to 1.0)
Example: 1.0

Spawn frequency multiplier. Lower values reduce spawn chance.

Default: 1.0 (100% spawn chance)

Example:

• 1.0 - Normal spawn rate
• 0.5 - 50% spawn rate (half as common)
• 0.1 - 10% spawn rate (very rare)

frequency_reduction_method

Type: String
Example: "DEFAULT"

Algorithm used for frequency reduction. Inherited from vanilla Minecraft's RandomSpreadStructurePlacement.

Default: "DEFAULT"

Note: This is an advanced feature. Most users should use the default value.

exclusion_zone

Type: Exclusion Zone Object
Example: See below

Standard exclusion zone from vanilla Minecraft. Prevents structures from spawning near other structure sets.

Example:

{
  "exclusion_zone": {
    "chunk_count": 10,
    "other_set": "minecraft:villages"
  }
}

Prevents spawning within 10 chunks of villages.

super_exclusion_zone

Type: Super Exclusion Zone Object
Example: See below

Enhanced exclusion zone unique to Moogs Structure Lib. More powerful than standard exclusion zones.

Structure:

{
  "super_exclusion_zone": {
    "other_set": "#namespace:tag_name",
    "chunk_count": 5,
    "allowed_chunk_count": 10
  }
}

Fields:

• other_set - Structure set tag or array of structure sets to avoid
• chunk_count - Exclusion radius in chunks
• allowed_chunk_count - Optional override for allowed distance

Example from MVS:

{
  "super_exclusion_zone": {
    "chunk_count": 3,
    "other_set": "#mvs:common_avoid"
  }
}

Prevents spawning within 3 chunks of any structure in the #mvs:common_avoid tag.

How it works:

• Checks if any structure from other_set exists within chunk_count chunks
• If found, prevents placement
• If allowed_chunk_count is specified and larger than chunk_count, allows placement only if structures exist within allowed_chunk_count range

spread_type

Type: String
Example: "LINEAR"

Distribution type for structure placement.

Options:

• "LINEAR" - Linear distribution (default)
• "TRIANGULAR" - Triangular distribution

Default: "LINEAR"

Note: Most users should use "LINEAR". "TRIANGULAR" creates a different distribution pattern but is rarely needed.

min_distance_from_world_origin

Type: Integer (0 to Integer.MAX_VALUE)
Example: 800

Minimum distance in blocks from world spawn (0, 0) before structures can spawn. Useful for rare structures that should only appear far from spawn.

Example:

{
  "min_distance_from_world_origin": 1000
}

Structures will only spawn at least 1000 blocks from spawn.

Common use cases:

• Rare structures (crystals, cathedrals)
• End-game content
• Structures that should be discovered through exploration

Complete Examples

Basic Placement

{
  "type": "moogs_structures:advanced_random_spread",
  "salt": 203698201,
  "spacing": 34,
  "separation": 26
}

Simple placement with no special features.

With Exclusion Zone

{
  "type": "moogs_structures:advanced_random_spread",
  "salt": 766544243,
  "spacing": 31,
  "separation": 26,
  "super_exclusion_zone": {
    "chunk_count": 3,
    "other_set": "#mvs:common_avoid"
  }
}

Prevents spawning near common structures.

Rare Structure

{
  "type": "moogs_structures:advanced_random_spread",
  "salt": 469982354,
  "spacing": 112,
  "separation": 62,
  "min_distance_from_world_origin": 800
}

Very rare structure that only spawns far from spawn.

Reduced Frequency

{
  "type": "moogs_structures:advanced_random_spread",
  "salt": 123456789,
  "spacing": 50,
  "separation": 35,
  "frequency": 0.5
}

Structure spawns at 50% of normal rate.

With Locate Offset

{
  "type": "moogs_structures:advanced_random_spread",
  "salt": 987654321,
  "spacing": 40,
  "separation": 30,
  "locate_offset": [8, 0, 8]
}

Locate command points to structure center offset by 8 blocks.

Understanding Spacing and Separation

Spacing vs Separation

Spacing controls average distance:

• Low spacing (20-30) = Common structures
• Medium spacing (50-70) = Uncommon structures
• High spacing (100+) = Rare structures

Separation controls minimum distance:

• Should be 60-80% of spacing value
• Prevents structures from spawning too close
• Too high = structures become too rare

The 1.65x Multiplier

Moogs Structure Lib multiplies both spacing and separation by 1.65 internally. This means:

Your JSON:

{
  "spacing": 34,
  "separation": 26
}

Internal values:

• Spacing: 34 × 1.65 = 56.1 chunks
• Separation: 26 × 1.65 = 42.9 chunks

Why? This provides better structure distribution and prevents clustering. Also in the early days of MVS i wanted to make all the structures rarer without having to individually change all of the values... and its too late to go back now xD

Exclusion Zones Explained

Standard Exclusion Zone

Vanilla Minecraft exclusion zone:

{
  "exclusion_zone": {
    "chunk_count": 10,
    "other_set": "minecraft:villages"
  }
}

Prevents spawning within 10 chunks of villages.

Super Exclusion Zone

Moogs Structure Lib enhanced exclusion:

{
  "super_exclusion_zone": {
    "chunk_count": 5,
    "other_set": "#mvs:common_avoid",
    "allowed_chunk_count": 10
  }
}

Behavior:

1. Checks for structures in other_set within chunk_count chunks
2. If found, prevents placement
3. If allowed_chunk_count is specified:
   • If structures exist within allowed_chunk_count range, allows placement
   • Otherwise, prevents placement

Use case: Allow structures only when other structures are nearby (or prevent when nearby).

Common Patterns

Common Structures

{
  "spacing": 20,
  "separation": 15
}

Spawns frequently, close together.

Uncommon Structures

{
  "spacing": 50,
  "separation": 35
}

Moderate rarity, reasonable spacing.

Rare Structures

{
  "spacing": 100,
  "separation": 80,
  "min_distance_from_world_origin": 1000
}

Very rare, far from spawn.

Structures Avoiding Others

{
  "spacing": 30,
  "separation": 25,
  "super_exclusion_zone": {
    "chunk_count": 5,
    "other_set": "#namespace:avoid_tag"
  }
}

Prevents overlap with tagged structures.

Troubleshooting

Structures not spawning?

• Verify spacing > separation (critical!)
• Check salt is unique
• Verify structure set JSON syntax
• Check exclusion zones aren't too restrictive

Structures too common/rare?

• Adjust spacing (higher = rarer)
• Remember the 1.65x multiplier
• Test in new worlds

Structures spawning too close?

• Increase separation
• Use exclusion zones
• Check other structure sets

Exclusion zones not working?

• Verify structure set tags exist
• Check tag syntax
• Ensure chunk_count is appropriate
• Test exclusion zone logic

Best Practices

1. Unique Salts - Never reuse salts across structure sets
2. Spacing > Separation - Always ensure spacing is greater
3. Appropriate Values - Match spacing to structure rarity
4. Exclusion Zones - Use them to prevent overlap
5. Testing - Always test structure placement in new worlds
6. Documentation - Comment your placement values for future reference

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Next: Learn about NBT Files to understand where structure files go!