在增强现实中计算与墙尺寸对应的图像尺寸并平滑拖动
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我正在创建一个应用程序，从库中选择图像并使用ARKit垂直平面检测将其放置在墙上。我也能够正确地缩放它，但拖动不是预期的。另外，我也对图像大小感到困惑。我想它就像假设墙壁是10英尺而我想要放置3 * 2英尺的图像。我引用了很多链接和docs.Below是渲染和添加地点图像的代码：
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for
anchor: ARAnchor)
if nodeWeCanChange == nil
guard let planeAnchor = anchor as? ARPlaneAnchor else return
let width = CGFloat(planeAnchor.extent.x)
let height = CGFloat(planeAnchor.extent.z)
nodeWeCanChange = SCNNode(geometry: SCNPlane(width: width,
height: height))
nodeWeCanChange?.position = SCNVector3(planeAnchor.center.x, 0,
planeAnchor.center.z)
nodeWeCanChange?.transform = SCNMatrix4MakeRotation(-Float.pi / 2.0, 1.0, 0.0, 0.0)
nodeWeCanChange?.geometry?.firstMaterial?.diffuse.contents = UIColor.white
DispatchQueue.main.async(execute:
node.addChildNode(self.nodeWeCanChange!)
self.zIndex = (self.nodeWeCanChange?.simdPosition.z)!)
func placeImage(image : UIImage)
guard let pointsPerInch = UIScreen.pointsPerInch else
return
let pixelWidth = (image.size.width) * (image.scale)
let pixelHeight = (image.size.height) * (image.scale)
let inchWidth = pixelWidth/pointsPerInch
let inchHeight = pixelHeight/pointsPerInch
let widthInMetres = (inchWidth * 2.54) / 100
let heightInMeters = (inchHeight * 2.54) / 100
let photo = SCNPlane(width: (widthInMetres), height: (heightInMeters))
nodeWeCanChange?.geometry = photo
nodeWeCanChange?.geometry?.firstMaterial?.diffuse.contents = image`
@objc func handleTap(_ gestureRecognize: ThresholdPanGesture)
// Function that handles drag
let position = gestureRecognize.location(in: augentedRealityView)
var foundNode:SCNNode? = nil
do
if gestureRecognize.state == .began
print("Pan state began")
//let hitTestOptions = [SCNHitTestOption: Any]()
let hitResult: [SCNHitTestResult] = (self.augentedRealityView?.hitTest(gestureRecognize.location(in: self.augentedRealityView), options: nil))!
guard let firstNode = hitResult.first else
return
print("first node =\(firstNode.node)")
if firstNode.node.isEqual(nodeWeCanChange)
foundNode = nodeWeCanChange
print("node found")
else if (firstNode.node.parent?.isEqual(nodeWeCanChange))! print("node found")
else return print("node not found")
latestTranslatePos = position
if gestureRecognize.state == .changed
let deltaX = Float(position.x - latestTranslatePos.x)/700
let deltaY = Float(position.y - latestTranslatePos.y)/700
nodeWeCanChange?.localTranslate(by: SCNVector3Make(deltaX, -deltaY , zIndex))
latestTranslatePos = position
print("Pan State Changed")
if gestureRecognize.state == .ended
print("Done moving object")
let deltaX = Float(position.x - latestTranslatePos.x)/700
let deltaY = Float(position.y - latestTranslatePos.y)/700
nodeWeCanChange?.localTranslate(by: SCNVector3Make(deltaX, -deltaY , zIndex))
latestTranslatePos = position
foundNode = nil
`
任何人都可以帮助我，我错过了什么？
答案
这里有两个问题...... ^ __________ ^。
关于规划你的qazxsw poi，最简单的方法是使用qazxsw poi，尽管你可以很容易地修改下面的例子。
假设你的内容被放置在SCNNode上并且你想在飞机上移动它然后你可以做这样的事情（假设你也选择了touches作为你的ARPlaneAnchor）在我的例子中将是图片：
SCNNode或者，您可以尝试以下方法：
nodeToDrag关于你的尺寸，你不清楚你想要做什么。但是这里有一个小例子，评论应该有所帮助：
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?)
//1. Get The Current Touch Point
guard let currentTouchPoint = touches.first?.location(in: self.augmentedRealityView),
//2. Get The Existing ARPlaneAnchor
let hitTest = augmentedRealityView.hitTest(currentTouchPoint, types: .existingPlane).first else return
//3. Convert To World Coordinates
let worldTransform = hitTest.worldTransform
//4. Set The New Position
let newPosition = SCNVector3(worldTransform.columns.3.x, worldTransform.columns.3.y, worldTransform.columns.3.z)
//5. Apply To The Node
nodeToDrag.simdPosition = float3(newPosition.x, newPosition.y, newPosition.z)
您还可以创建一个辅助函数，例如：
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?)
//1. Get The Current Touch Point
guard let currentTouchPoint = touches.first?.location(in: self.augmentedRealityView),
//2. Get The Existing ARPlaneAnchor
let hitTest = augmentedRealityView.hitTest(currentTouchPoint, types: .existingPlane).first else return
//3. Convert To Local Coordinates
nodeToDrag.simdPosition.x = Float(hitTest.localTransform.columns.3.x)
nodeToDrag.simdPosition.y = Float(-hitTest.localTransform.columns.3.z)
您可以根据锚点的范围来缩放图片，例如：
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor)
//1. Check We Have An ARPlaneAnchor
guard let planeAnchor = anchor as? ARPlaneAnchor else return
//2. Get The Approximate Width & Height Of The Anchor
let width = CGFloat(planeAnchor.extent.x)
let height = CGFloat(planeAnchor.extent.z)
//3. Create A Dummy Wall To Illustrate The Vertical Plane
let dummyWall = SCNNode(geometry: SCNPlane(width: width, height: height))
dummyWall.geometry?.firstMaterial?.diffuse.contents = UIColor.black
dummyWall.opacity = 0.5
dummyWall.eulerAngles.x = -.pi/2
node.addChildNode(dummyWall)
//4. Create A Picture Which Will Be Half The Size Of The Wall
let picture = SCNNode(geometry: SCNPlane(width: width/2, height: height/2))
picture.geometry?.firstMaterial?.diffuse.contents = UIColor.white
//5. Add It To The Dummy Wall (As We Dont Assign A Position It Will Be Centered Automatically At SCNVector3Zero)
dummyWall.addChildNode(picture)
//6. To Prevent Z-Fighting Move The Picture Forward Slightly
picture.position.z = 0.0001
更新：
既然你无法让这个例子起作用，并且现在对你的要求更加具体，那么这里是一个完全有效的例子（需要稍加调整），但它应该足以让你指向正确的方向：
//--------------------------
//MARK: - CGFloat Extensions
//--------------------------
extension CGFloat
/// Desired Scale Factor
enum Scalar
case Quarter
case Third
case Half
case ThreeQuarters
case FullSize
var value: CGFloat
switch self
case .Quarter: return 0.25
case .Third: return 0.33
case .Half: return 0.5
case .ThreeQuarters: return 0.75
case .FullSize: return 1
/// Returns A CGFloat Based On The Desired Scale
///
/// - Parameter size: Scalar
/// - Returns: CGFloat
func scaledToSize(_ size: Scalar) -> CGFloat
return self * size.value
希望能帮助到你...
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