我正在尝试扫描参考图像，然后在打印的参考图像上方显示图像本身。 “虚拟”图像尺寸应与打印尺寸相同。
我的想法：获取打印的参考图像的大小，然后将SCNNode中的图像缩放至该大小（或将SCNNode缩放至此大小？）
但是：1->如何获取打印图像的大小，2->用于缩放SCNNode，我也需要此节点的大小。如何获得？
import UIKit
import SceneKit
import ARKit
import AVKit
import AVFoundation
class ViewController: UIViewController, ARSCNViewDelegate {
@IBOutlet var sceneView: ARSCNView!
private var planeNode: SCNNode?
private var imageNode: SCNNode?
private var animationInfo: AnimationInfo?
private var currentMediaName: String?
private var scrollView: UIScrollView!
override func viewDidLoad() {
super.viewDidLoad()
let scene = SCNScene()
sceneView.scene = scene
sceneView.delegate = self
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
// Load reference images to look for from "AR Resources" folder
guard let referenceImages = ARReferenceImage.referenceImages(inGroupNamed: "AR Resources", bundle: nil) else {
fatalError("Missing expected asset catalog resources.")
}
// Create a session configuration
let configuration = ARWorldTrackingConfiguration()
// Add previously loaded images to ARScene configuration as detectionImages
configuration.detectionImages = referenceImages
// Run the view's session
sceneView.session.run(configuration)
let tap = UITapGestureRecognizer(target: self, action: #selector(handleTap(rec:)))
//Add recognizer to sceneview
sceneView.addGestureRecognizer(tap)
}
//Method called when tap
@objc func handleTap(rec: UITapGestureRecognizer){
let location: CGPoint = rec.location(in: sceneView)
let hits = self.sceneView.hitTest(location, options: nil)
if !hits.isEmpty{
let tappedNode = hits.first?.node
if tappedNode != nil && tappedNode?.name != nil{
let stringArr = tappedNode?.name?.components(separatedBy: "-")
let name = stringArr! [0]
let size = stringArr! [1].components(separatedBy: ",")
let width = Float(size [0])
let height = Float(size [1])
loadReferenceImage(tappedNode: tappedNode!, name: (name), width: width!, height: height!)
}
}
}
private func playVideo() {
guard let path = Bundle.main.path(forResource: "video", ofType:"m4v") else {
debugPrint("video.m4v not found")
return
}
let player = AVPlayer(url: URL(fileURLWithPath: path))
let playerController = AVPlayerViewController()
playerController.player = player
present(playerController, animated: true) {
player.play()
}
}
func loadReferenceImage(tappedNode: SCNNode, name: String, width: Float, height: Float){
print("TAP")
print(name)
let currentNode = tappedNode.parent
if let image = UIImage(named: "col" + name){
let childNodes = currentNode?.childNodes
for node in (childNodes)!{
node.removeFromParentNode()
}
let newImage = UIImage(named: "col" + name)
let newnode = SCNNode(geometry: SCNPlane(width: CGFloat(width), height: CGFloat(height)))
newnode.geometry?.firstMaterial?.diffuse.contents = newImage
newnode.scale = SCNVector3(x: 10, y: 10, z: 10)
currentNode?.removeAnimation(forKey: "spin_around")
let rotation = SCNVector3((currentNode?.eulerAngles.x)!-0.95,(currentNode?.eulerAngles.y)!,(currentNode?.eulerAngles.z)!)
currentNode?.eulerAngles = rotation
//SIZE??????
let nodex = currentNode?.scale.x
let nodey = currentNode?.scale.y
let nodez = currentNode?.scale.z
let factorx = width / nodex!
let factory = height / nodey!
currentNode?.addChildNode(newnode)
}
}
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
guard let imageAnchor = anchor as? ARImageAnchor else {
return
}
// 1. Load scene.
let planeScene = SCNScene(named: "art.scnassets/plane.scn")!
let planeNode = planeScene.rootNode.childNode(withName: "planeRootNode", recursively: true)!
// 2. Calculate size based on planeNode's bounding box.
let (min, max) = planeNode.boundingBox
let size = SCNVector3Make(max.x - min.x, max.y - min.y, max.z - min.z)
// 3. Calculate the ratio of difference between real image and object size.
// Ignore Y axis because it will be pointed out of the image.
let widthRatio = Float(imageAnchor.referenceImage.physicalSize.width)/1.2
let heightRatio = Float(imageAnchor.referenceImage.physicalSize.height)/1.2
let width = imageAnchor.referenceImage.physicalSize.width
let height = imageAnchor.referenceImage.physicalSize.height
let prefix = "-"
let imageSize = width.description + "," + height.description
let targetName = imageAnchor.referenceImage.name! + prefix + imageSize
// Pick smallest value to be sure that object fits into the image.
let finalRatio = [widthRatio, heightRatio].min()!
// 4. Set transform from imageAnchor data.
planeNode.transform = SCNMatrix4(imageAnchor.transform)
// 5. Animate appearance by scaling model from 0 to previously calculated value.
let appearanceAction = SCNAction.scale(to: CGFloat(finalRatio), duration: 0.4)
//test
appearanceAction.timingMode = .easeOut
// Set initial scale to 0.
planeNode.scale = SCNVector3Make(0 , 0, 0)
//rotate y
let spin = CABasicAnimation(keyPath: "rotation")
spin.fromValue = NSValue(scnVector4: SCNVector4(x: 0, y: 1, z: 0, w: 0))
spin.toValue = NSValue(scnVector4: SCNVector4(x: 0, y: 1, z: 0, w: Float(CGFloat(2 * Double.pi))))
spin.duration = 4
spin.repeatCount = .infinity
planeNode.addAnimation(spin, forKey: "spin_around")
// Add to root node.
sceneView.scene.rootNode.addChildNode(planeNode)
// Run the appearance animation.
planeNode.runAction(appearanceAction)
planeNode.name = targetName
let nodes = planeNode.childNodes
for node in nodes{
node.name = targetName
}
self.planeNode = planeNode
self.imageNode = node
}
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor, updateAtTime time: TimeInterval) {
guard let imageNode = imageNode, let planeNode = planeNode else {
return
}
// 1. Unwrap animationInfo. Calculate animationInfo if it is nil.
guard let animationInfo = animationInfo else {
refreshAnimationVariables(startTime: time,
initialPosition: planeNode.simdWorldPosition,
finalPosition: imageNode.simdWorldPosition,
initialOrientation: planeNode.simdWorldOrientation,
finalOrientation: imageNode.simdWorldOrientation)
return
}
// 2. Calculate new animationInfo if image position or orientation changed.
if !simd_equal(animationInfo.finalModelPosition, imageNode.simdWorldPosition) || animationInfo.finalModelOrientation != imageNode.simdWorldOrientation {
refreshAnimationVariables(startTime: time,
initialPosition: planeNode.simdWorldPosition,
finalPosition: imageNode.simdWorldPosition,
initialOrientation: planeNode.simdWorldOrientation,
finalOrientation: imageNode.simdWorldOrientation)
}
// 3. Calculate interpolation based on passedTime/totalTime ratio.
let passedTime = time - animationInfo.startTime
var t = min(Float(passedTime/animationInfo.duration), 1)
// Applying curve function to time parameter to achieve "ease out" timing
t = sin(t * .pi * 0.5)
// 4. Calculate and set new model position and orientation.
let f3t = simd_make_float3(t, t, t)
planeNode.simdWorldPosition = simd_mix(animationInfo.initialModelPosition, animationInfo.finalModelPosition, f3t)
planeNode.simdWorldOrientation = simd_slerp(animationInfo.initialModelOrientation, animationInfo.finalModelOrientation, t)
//planeNode.simdWorldOrientation = imageNode.simdWorldOrientation
guard let currentImageAnchor = anchor as? ARImageAnchor else { return }
}
func refreshAnimationVariables(startTime: TimeInterval, initialPosition: float3, finalPosition: float3, initialOrientation: simd_quatf, finalOrientation: simd_quatf) {
let distance = simd_distance(initialPosition, finalPosition)
// Average speed of movement is 0.15 m/s.
let speed = Float(0.15)
// Total time is calculated as distance/speed. Min time is set to 0.1s and max is set to 2s.
let animationDuration = Double(min(max(0.1, distance/speed), 2))
// Store animation information for later usage.
animationInfo = AnimationInfo(startTime: startTime,
duration: animationDuration,
initialModelPosition: initialPosition,
finalModelPosition: finalPosition,
initialModelOrientation: initialOrientation,
finalModelOrientation: finalOrientation)
}
}
答案 0 :(得分：1)
为此，我认为首先需要通过
获取Pixels的{{1}}中的大小
将大小值乘以scale属性中的值以获得 图片的像素尺寸。
这样的例子就像这样：
UIImage在guard let image = UIImage(named: "launchScreen") else { return }
let pixelWidth = image.size.width * image.scale
let pixelHeight = image.size.height * image.scale
print(pixelWidth, pixelHeight)
中制作时，我的图片大小为3072 x 4099，当我在控制台中记录结果时，尺寸也相同。
现在，这里最棘手的部分是将像素计算为可以在Adobe Illustrator中使用的大小，记住不同的设备具有不同的PPI（ARKit）密度。
在我的示例中，我将使用Pixels Per Inch的PPI（即401）。
iPhone7Plus现在我们有了以米为单位的图像大小，创建一个具有该大小的 //1. Get The PPI Of The iPhone7Plus
let iphone7PlusPixelsPerInch: CGFloat = 401
//2. To Get The Image Size In Inches We Need To Divide By The PPI
let inchWidth = pixelWidth/iphone7PlusPixelsPerInch
let inchHeight = pixelHeight/iphone7PlusPixelsPerInch
//3. Calculate The Size In Metres (There Are 2.54 Cm's In An Inch)
let widthInMetres = (inchWidth * 2.54) / 100
let heightInMeters = (inchHeight * 2.54) / 100
很简单，例如：
SCNNode希望有帮助...
P.S：这可能有助于您获取屏幕的PPI（marchv/UIScreenExtension）