# Masks

## Introduction

This page is currently being revised.

## Masks

**To learn about basic masks that WorldEdit offers please click** [**here**](https://worldedit.readthedocs.io/en/latest/usage/general/masks/)**.**

A mask is a restriction on an edit for when blocks are placed e.g. only replace blocks below stone. Global masks apply to all edits, brush masks apply to just the current brush.

## Syntax

### Blocks

Use the name or id of a block (e.g. `stone`).

### Multiple masks

Use `,`(OR) or `&`(AND) to separate multiple masks. e.g. `grass_block,$desert`

### Arguments

Mask arguments should be inside square brackets e.g. `#offset[0][5][3]`

## Setting a mask

###

Perm: `worldedit.global-mask` Desc: This command applies a mask(s) to all your WorldEdit actions globally. This command masks based on the destination blocks (i.e. the blocks in the world).

###

Perm: `worldedit.global-mask`\
Desc: The global source mask applies to all edits you do and masks based on the source blocks (e.g. the blocks in your clipboard)

###

Perm: `worldedit.brush.options.mask`\
Desc: Set the brush destination mask

###

Perm: `worldedit.brush.options.mask`\
Desc: Set the brush source mask

## Mask list

### #offset \<dx> \<dy> \<dz> \<mask>

**Desc**: Offset a mask

### % \<chance>

**Desc**: percentage chance

### #id

**Desc**: Restrict to initial id

### #existing

**Desc**: If there is a non air block

### #data

**Desc**: Restrict to initial data

### { \<min> \<max>

**Desc**: Restricts blocks to within a specific radius range of the initial block

### #surface

**Desc**: Restrict to surfaces (any solid block touching air)

### = \<expression>

**Desc**: expression mask

### ! \<mask>

**Desc**: Negate another mask

### $ \<biome>

**Desc**: in a specific biome. For a list of biomes use //biomelist

### #region

**Desc**: inside the provided selection

### \~ \<mask> \[min=1] \[max=8]

**Desc**: Adjacent to a specific number of other blocks

### / \<min> \<max>

**Desc**: Restrict to specific terrain angle\
The -o flag will only overlayExample: /\[0d]\[45d]\
Explanation: Allows any block where the adjacent block is between 0 and 45 degrees.\
Example: /\[3]\[20]\
Explanation: Allows any block where the adjacent block is between 3 and 20 blocks below

### #dregion

**Desc**: inside the player’s selection

### #xaxis

**Desc**: Restrict to initial x axis

### #liquid

**Desc**: If there is a solid block

### true

**Desc**: Always true

### false

**Desc**: Always false

### > \<mask>

**Desc**: above a specific block

### #wall

**Desc**: Restrict to walls (any block n,e,s,w of air)

### #zaxis

**Desc**: Restrict to initial z axis

### #yaxis

**Desc**: Restrict to initial y axis

### < \<mask>

**Desc**: below a specific block

### #simplex \<scale=10> \<min=0> \<max=100>\`

**Desc**: Use simplex noise as the mask

### #solid

**Desc**: If there is a solid block

### #surfaceangle\[min]\[max]\[depth] (material)

**Desc**: Replace the surface of blocks


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