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  "documentType" : "symbol",
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  "identifier" : "/documentation/ARKit/ARPlaneAnchor/center",
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  "title" : "center"
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# center

The center point of the plane relative to its anchor position.

```
var center: simd_float3 { get }
```

## Discussion

When ARKit first detects a plane, the resulting [`ARPlaneAnchor`](/documentation/ARKit/ARPlaneAnchor) object has a [`center`](/documentation/ARKit/ARPlaneAnchor/center) value of `(0,0,0)`, indicating that the translation portion of the anchor’s [`transform`](/documentation/ARKit/ARAnchor/transform) value locates the plane’s center point.

As scene analysis and plane detection continues, ARKit may determine that a previously detected plane anchor is part of a larger real-world surface, increasing the [`extent`](/documentation/ARKit/ARPlaneAnchor/extent) width and length values. The plane’s new boundaries may not be symmetric around its initial position, so the [`center`](/documentation/ARKit/ARPlaneAnchor/center) point changes relative to the anchor’s (unchanged) [`transform`](/documentation/ARKit/ARAnchor/transform) matrix.

Although the type of this property is <doc://com.apple.documentation/documentation/simd/vector_float3>, a plane anchor is always two-dimensional, and is always positioned in only the x and z directions relative to its [`transform`](/documentation/ARKit/ARAnchor/transform) position. (That is, the y-component of this vector is always zero.)

---

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