<!--
{
  "availability" : [
    "iOS: 18.0.0 -",
    "iPadOS: 18.0.0 -",
    "macOS: 15.0.0 -",
    "tvOS: 18.0.0 -",
    "visionOS: 2.0.0 -",
    "watchOS: 27.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Vision",
  "identifier" : "/documentation/Vision/QuadrilateralProviding",
  "metadataVersion" : "0.1.0",
  "role" : "Protocol",
  "symbol" : {
    "kind" : "Protocol",
    "modules" : [
      "Vision"
    ],
    "preciseIdentifier" : "s:6Vision22QuadrilateralProvidingP"
  },
  "title" : "QuadrilateralProviding"
}
-->

# QuadrilateralProviding

A protocol for objects that have a bounding quadrilateral.

```
protocol QuadrilateralProviding : BoundingBoxProviding
```

## Topics

### Getting the normalized points

[`var bottomLeft: NormalizedPoint`](/documentation/Vision/QuadrilateralProviding/bottomLeft)

The coordinates of the lower-left corner of the quadrilateral.

[`var bottomRight: NormalizedPoint`](/documentation/Vision/QuadrilateralProviding/bottomRight)

The coordinates of the lower-right corner of quadrilateral.

[`var topLeft: NormalizedPoint`](/documentation/Vision/QuadrilateralProviding/topLeft)

The coordinates of the upper-left corner of the quadrilateral.

[`var topRight: NormalizedPoint`](/documentation/Vision/QuadrilateralProviding/topRight)

The coordinates of the upper-right corner of the quadrilateral.

## Relationships

### Inherits From

[`BoundingBoxProviding`](/documentation/Vision/BoundingBoxProviding)

### Conforming Types

[`BarcodeObservation`](/documentation/Vision/BarcodeObservation)

[`DetectedDocumentObservation`](/documentation/Vision/DetectedDocumentObservation)

[`RecognizedTextObservation`](/documentation/Vision/RecognizedTextObservation)

[`RectangleObservation`](/documentation/Vision/RectangleObservation)

[`TextObservation`](/documentation/Vision/TextObservation)

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)