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# RealityRenderer.CameraOutput.RelativeViewport

Structure defining a viewport for rendering with a camera.

```
struct RelativeViewport
```

## Overview

The units are relative to output texture size.
To map normalized-device coordinates to the whole texture:

```swift
viewport = RealityRenderer.CameraOutput.RelativeViewport(originX: 0.0, originY: 0.0, width: 1.0, height: 1.0)
```

Assigning values more than 1.0 to [`width`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/width)
or [`height`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/height)
stretches the viewport in horizontal and vertical directions.

Assigning values less than 0.0 to [`originX`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/originX)
or [`originY`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/originY)
shifts the viewport into negative X and negative Y directions.

## Topics

### Initializers

[`init(originX: Double, originY: Double, width: Double, height: Double)`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/init(originX:originY:width:height:))

### Instance Properties

[`var height: Double`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/height)

[`var originX: Double`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/originX)

[`var originY: Double`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/originY)

[`var width: Double`](/documentation/RealityKit/RealityRenderer/CameraOutput/RelativeViewport/width)

---

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