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    "iPadOS: 11.0.0 -"
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  "documentType" : "symbol",
  "framework" : "ARKit",
  "identifier" : "/documentation/ARKit/ARFaceAnchor/BlendShapeLocation",
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  "title" : "ARFaceAnchor.BlendShapeLocation"
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# ARFaceAnchor.BlendShapeLocation

Identifiers for specific facial features, for use with coefficients describing the relative movements of those features.

```
struct BlendShapeLocation
```

## Discussion

The [`blendShapes`](/documentation/ARKit/ARFaceAnchor/blendShapes) dictionary provided by an [`ARFaceAnchor`](/documentation/ARKit/ARFaceAnchor) object describes the facial expression of a detected face in terms of the movements of specific facial features. For each key in the dictionary, the corresponding value is a floating point number indicating the current position of that feature relative to its neutral configuration, ranging from `0.0` (neutral) to `1.0` (maximum movement).

ARKit provides many blend shape coefficients, resulting in a detailed model of a facial expression; however, you can use as many or as few of the coefficients as you desire to create a visual effect. For example, you might animate a simple cartoon character using only the [`jawOpen`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/jawOpen), [`eyeBlinkLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeBlinkLeft), and [`eyeBlinkRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeBlinkRight) coefficients. A professional 3D artist could create a detailed character model rigged for realistic animation using a larger set, or the entire set, of coefficients.

> Note:
> In the naming of blend shape coefficients, the left and right directions are relative to the face. That is, the ``doc://com.apple.arkit/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeBlinkRight`` coefficient refers to the face’s right eye. ARKit views running a face-tracking session mirror the camera image, so the face’s right eye appears on the right side in the view.

## Topics

### Left Eye

[`eyeBlinkLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeBlinkLeft)

The coefficient describing closure of the eyelids over the left eye.

[`eyeLookDownLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookDownLeft)

The coefficient describing movement of the left eyelids consistent with a downward gaze.

[`eyeLookInLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookInLeft)

The coefficient describing movement of the left eyelids consistent with a rightward gaze.

[`eyeLookOutLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookOutLeft)

The coefficient describing movement of the left eyelids consistent with a leftward gaze.

[`eyeLookUpLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookUpLeft)

The coefficient describing movement of the left eyelids consistent with an upward gaze.

[`eyeSquintLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeSquintLeft)

The coefficient describing contraction of the face around the left eye.

[`eyeWideLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeWideLeft)

The coefficient describing a widening of the eyelids around the left eye.

### Right Eye

[`eyeBlinkRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeBlinkRight)

The coefficient describing closure of the eyelids over the right eye.

[`eyeLookDownRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookDownRight)

The coefficient describing movement of the right eyelids consistent with a downward gaze.

[`eyeLookInRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookInRight)

The coefficient describing movement of the right eyelids consistent with a leftward gaze.

[`eyeLookOutRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookOutRight)

The coefficient describing movement of the right eyelids consistent with a rightward gaze.

[`eyeLookUpRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeLookUpRight)

The coefficient describing movement of the right eyelids consistent with an upward gaze.

[`eyeSquintRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeSquintRight)

The coefficient describing contraction of the face around the right eye.

[`eyeWideRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/eyeWideRight)

The coefficient describing a widening of the eyelids around the right eye.

### Mouth and Jaw

[`jawForward`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/jawForward)

The coefficient describing forward movement of the lower jaw.

[`jawLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/jawLeft)

The coefficient describing leftward movement of the lower jaw.

[`jawRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/jawRight)

The coefficient describing rightward movement of the lower jaw.

[`jawOpen`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/jawOpen)

The coefficient describing an opening of the lower jaw.

[`mouthClose`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthClose)

The coefficient describing closure of the lips *independent of jaw position*.

[`mouthFunnel`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthFunnel)

The coefficient describing contraction of both lips into an open shape.

[`mouthPucker`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthPucker)

The coefficient describing contraction and compression of both closed lips.

[`mouthLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthLeft)

The coefficient describing leftward movement of both lips together.

[`mouthRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthRight)

The coefficient describing rightward movement of both lips together.

[`mouthSmileLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthSmileLeft)

The coefficient describing upward movement of the left corner of the mouth.

[`mouthSmileRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthSmileRight)

The coefficient describing upward movement of the right corner of the mouth.

[`mouthFrownLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthFrownLeft)

The coefficient describing downward movement of the left corner of the mouth.

[`mouthFrownRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthFrownRight)

The coefficient describing downward movement of the right corner of the mouth.

[`mouthDimpleLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthDimpleLeft)

The coefficient describing backward movement of the left corner of the mouth.

[`mouthDimpleRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthDimpleRight)

The coefficient describing backward movement of the right corner of the mouth.

[`mouthStretchLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthStretchLeft)

The coefficient describing leftward movement of the left corner of the mouth.

[`mouthStretchRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthStretchRight)

The coefficient describing rightward movement of the left corner of the mouth.

[`mouthRollLower`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthRollLower)

The coefficient describing movement of the lower lip toward the inside of the mouth.

[`mouthRollUpper`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthRollUpper)

The coefficient describing movement of the upper lip toward the inside of the mouth.

[`mouthShrugLower`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthShrugLower)

The coefficient describing outward movement of the lower lip.

[`mouthShrugUpper`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthShrugUpper)

The coefficient describing outward movement of the upper lip.

[`mouthPressLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthPressLeft)

The coefficient describing upward compression of the lower lip on the left side.

[`mouthPressRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthPressRight)

The coefficient describing upward compression of the lower lip on the right side.

[`mouthLowerDownLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthLowerDownLeft)

The coefficient describing downward movement of the lower lip on the left side.

[`mouthLowerDownRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthLowerDownRight)

The coefficient describing downward movement of the lower lip on the right side.

[`mouthUpperUpLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthUpperUpLeft)

The coefficient describing upward movement of the upper lip on the left side.

[`mouthUpperUpRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/mouthUpperUpRight)

The coefficient describing upward movement of the upper lip on the right side.

### Eyebrows, Cheeks, and Nose

[`browDownLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/browDownLeft)

The coefficient describing downward movement of the outer portion of the left eyebrow.

[`browDownRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/browDownRight)

The coefficient describing downward movement of the outer portion of the right eyebrow.

[`browInnerUp`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/browInnerUp)

The coefficient describing upward movement of the inner portion of both eyebrows.

[`browOuterUpLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/browOuterUpLeft)

The coefficient describing upward movement of the outer portion of the left eyebrow.

[`browOuterUpRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/browOuterUpRight)

The coefficient describing upward movement of the outer portion of the right eyebrow.

[`cheekPuff`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/cheekPuff)

The coefficient describing outward movement of both cheeks.

[`cheekSquintLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/cheekSquintLeft)

The coefficient describing upward movement of the cheek around and below the left eye.

[`cheekSquintRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/cheekSquintRight)

The coefficient describing upward movement of the cheek around and below the right eye.

[`noseSneerLeft`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/noseSneerLeft)

The coefficient describing a raising of the left side of the nose around the nostril.

[`noseSneerRight`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/noseSneerRight)

The coefficient describing a raising of the right side of the nose around the nostril.

### Tongue

[`tongueOut`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/tongueOut)

The coefficient describing extension of the tongue.

### Creating a Blend Shape Location

[`init(rawValue:)`](/documentation/ARKit/ARFaceAnchor/BlendShapeLocation/init(rawValue:))

Creates a blend shape location.


---

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