我可以使用ARKit 2获取眼睛的测量值
我正在开发一个项目，需要每只眼睛的大小和眼睛之间的距离使用ARKit和iPhone X上的真实深度相机以及Xcode 10 beta 4上的iOS 12 beta 4。
由于我是ARKit的新手，我在网上搜索的解决方案很少。 但是，我在Apple开发者门户网站上看到了一个演示代码 。 在该代码中，我尝试获取所需的值。
还提到了@rickster 的答案
我在ARSCNFaceGeometry和ARFaceAnchor上工作以获取少量值。
func update(withFaceAnchor anchor: ARFaceAnchor) { let faceGeometry = geometry as! ARSCNFaceGeometry faceGeometry.update(from: anchor.geometry) print("\nLook at Point :", anchor.lookAtPoint, "\nLeft :", anchor.leftEyeTransform, "\nRight :", anchor.rightEyeTransform) } 输出：
看点：float3（0.14502259,0.2905016,0.97809345）
左：simd_float4x4（[[0.99312633，-0.030915117，-0.11289084,0.0）]，[0.0,0.9644885，-0.26412484,0.0）]，[0.11704737,0.26230934,0.9578589,0.0）]，[0.03311049,0.028666705,0.028539032,1.0） ]]）
右：simd_float4x4（[[0.9830616，-0.047965277，-0.17688738,0.0）]，[0.0,0.96514606，-0.26171172,0.0）]，[0.18327524,0.25727874,0.94879806,0.0）]，[ – 0.032072492,0.028482603,0.028181288,1.0 ）]]）
问题
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如何翻译这些值以使用它并获得一些坐标？
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这段代码会帮助我实现每只眼睛的大小和眼睛之间的距离。 如果不是，那么我该怎么做才能进行测量？
你可以从变换中得到vector3：
var leftEyePosition = SCNVector3(leftTransform.columns.3.x, leftTransform.columns.3.y, leftTransform.columns.3.z) var rightEyePosition = SCNVector3(rightTransform.columns.3.x, rightTransform.columns.3.y, rightTransform.columns.3.z)
然后你可以像这样得到2 SCNVector3的距离。
let d = distance(float3(leftEyePosition), float3(rightEyePosition))
结果将以米为单位，因此您可能希望将d除以100
在ARKit 2 / Xcode 10 beta 6 / iOS 12中，“lookAtPoint”无效; 但是我能够得到“leftEyeTransform”和“rightEyeTransform”，然后可以使用这个代码计算眼间距离（在不同距离的两个人身上测试并用尺子validation！）：
func update(withFaceAnchor anchor: ARFaceAnchor) { let faceGeometry = occlusionNode.geometry as! ARSCNFaceGeometry faceGeometry.update(from: anchor.geometry) print("\nLook at Point:", anchor.lookAtPoint, "\nLeft:", anchor.leftEyeTransform, "\nRight:", anchor.rightEyeTransform) var leftEyePosition = SCNVector3(anchor.leftEyeTransform.columns.3.x, anchor.leftEyeTransform.columns.3.y, anchor.leftEyeTransform.columns.3.z) var rightEyePosition = SCNVector3(anchor.rightEyeTransform.columns.3.x, anchor.rightEyeTransform.columns.3.y, anchor.rightEyeTransform.columns.3.z) let d = distance(float3(leftEyePosition), float3(rightEyePosition)) print("\nInter-eye distance in centimeters: ", d * 100)
}
一些示例输出：
Look at Point: float3(0.0, 0.0, 0.0) Left: simd_float4x4([[0.9997796, -0.0031222918, 0.020761598, 0.0)], [0.0, 0.98888004, 0.14871553, 0.0)], [-0.020995062, -0.14868274, 0.98866206, 0.0)], [0.031608228, 0.031428084, 0.026632207, 1.0)]]) Right: simd_float4x4([[0.99887705, 0.007054036, -0.04684897, 0.0)], [0.0, 0.9888536, 0.14889139, 0.0)], [0.047377057, -0.1487242, 0.98774314, 0.0)], [-0.031623494, 0.03171173, 0.02669965, 1.0)]]) Inter-eye distance in centimeters: 6.32324
注意：
没有简单的方法来实际获得学生自己的大小。 有关更多信息，请参阅此StackOverFlow主题和Rickster提供的答案： 获取 ARKit中的大小
但是，使用leftEyeTransform和rightEyeTransforms眼睛之间的估计距离：
变换矩阵表示面部左眼和右眼的位置和方向。
您感兴趣的是这些包含我们需要的数据的第3列。
计算距离的一种简单方法是使用不需要任何额外扩展的GLK助手。
这样的例子可能看起来像这样：
//---------------------- //MARK ARSCNViewDelegate //---------------------- extension ViewController: ARSCNViewDelegate{ /// Creates A GLKVector3 From a Simd_Float4 /// /// - Parameter transform: simd_float4 /// - Returns: GLKVector3 func glkVector3FromARFaceAnchorTransform(_ transform: simd_float4) -> GLKVector3{ return GLKVector3Make(transform.x, transform.y, transform.z) } func renderer(_ renderer: SCNSceneRenderer, didUpdate node: SCNNode, for anchor: ARAnchor) { //1. Check We Have A Valid ARFaceAnchor guard let faceAnchor = anchor as? ARFaceAnchor else { return } //2. Get The Position Of The Left & Right Eyes let leftEyePosition = glkVector3FromARFaceAnchorTransform(faceAnchor.leftEyeTransform.columns.3) let righEyePosition = glkVector3FromARFaceAnchorTransform(faceAnchor.rightEyeTransform.columns.3) //3. Calculate The Distance Between Them let distanceBetweenEyesInMetres = GLKVector3Distance(leftEyePosition, righEyePosition) let distanceBetweenEyesInCM = distanceBetweenEyesInMetres/100 print("The Distance Between The Eyes Is Approximatly \(distanceBetweenEyesInCM)") } }
希望能帮助到你…