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# Entity.WriteOptions

A set of options that control how RealityKit writes entities to a reality file.

```
struct WriteOptions
```

## Overview

Use [`Entity.WriteOptions`](/documentation/RealityKit/Entity/WriteOptions) to tune the tradeoff between export speed, file size, and runtime
cost when you save a scene to a `.reality` file.

Pass a value of this type to [`write(to:options:)`](/documentation/RealityKit/Entity/write(to:options:)) or [`write(to:options:)`](/documentation/RealityKit/Entity/ConfigurationCatalog/write(to:options:))
as an array literal containing one or more option values.

```swift
let combinedOptions: Entity.WriteOptions = [
    .preferFastExport,
    .preferSmallTextureFiles(quality: .standard)
]
```

## Expediting Reality File Exports

The [`preferFastExport`](/documentation/RealityKit/Entity/WriteOptions/preferFastExport) reduces the time required to write
a reality file but produces a larger file on disk.

## Reducing Texture File Size

The [`preferSmallTextureFiles(quality:)`](/documentation/RealityKit/Entity/WriteOptions/preferSmallTextureFiles(quality:)) method returns options
that instruct RealityKit to encode textures using smaller file representations,  at the cost of longer
load times and higher memory usage. Specify a
[`Entity.WriteOptions.TextureQuality`](/documentation/RealityKit/Entity/WriteOptions/TextureQuality) level to control the tradeoff between visual fidelity
and file size.

## Topics

### Configuring export options

[`static var preferFastExport: Entity.WriteOptions`](/documentation/RealityKit/Entity/WriteOptions/preferFastExport)

Expedite the reality file export when possible.

[`static func preferSmallTextureFiles(quality: Entity.WriteOptions.TextureQuality) -> Entity.WriteOptions`](/documentation/RealityKit/Entity/WriteOptions/preferSmallTextureFiles(quality:))

Reduce textures’ file size while preserving its dimensions.

[`struct TextureQuality`](/documentation/RealityKit/Entity/WriteOptions/TextureQuality)

A texture quality level.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Equatable`](/documentation/Swift/Equatable)

[`ExpressibleByArrayLiteral`](/documentation/Swift/ExpressibleByArrayLiteral)

[`Sendable`](/documentation/Swift/Sendable)

[`Hashable`](/documentation/Swift/Hashable)

---

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