ARKit 检测平面之间的交叉点
ARKit detecting intersection between planes
我正在使用 ARKit（带有 Scene Kit）并试图找到一种方法来获取 ARReference 图像和 Horizontal ARPlaneDetection 之间的交集，以便在检测到的图像正前方的表面上显示 3D 角色，例如, 在红圈内生成见下图
目前我能够让角色在检测到的图像前面生成，但是，角色漂浮在空中而不是站在表面上。
let realWorldPositon = SCNVector3Make(anchor.transform.columns.3.x, anchor.transform.columns.3.y, anchor.transform.columns.3.z)
let hitTest = self.sceneView.scene.rootNode.hitTestWithSegment(from: self.sceneView.scene.rootNode.worldPosition, to: realWorldPositon, options: nil)
overlayNode.position = SCNVector3Make((hitTest.first?.worldCoordinates.x)!, 0, (hitTest.first?.worldCoordinates.z)!)
self.sceneView.scene.rootNode.addChildNode(overlayNode)
如有任何帮助，我们将不胜感激，谢谢！
我认为您使用 hitTestWithSegment 函数来检测 ARImageAnchor 和 ARPlaneAnchor 之间的交集是正确的。
我没有试图解释我尝试回答的每一步，而是提供了完整注释的代码，因此它应该是相当自我解释的。
我的例子运行得相当好（虽然它肯定不完美）并且肯定需要一些调整。
例如，您需要更准确地确定从 ARReferenceImage 到 ARPlaneAnchor 等的距离
我可以将模型（口袋妖怪）放置在正确的水平并且非常靠近 ARReferenceImage 的前面，尽管它需要调整。
话虽如此，我认为这将是您开始精炼代码并获得更准确结果的一个相当好的基础。
然而，值得注意的是，我刚刚启用了一个 ARPlaneAnchor 来检测（只是为了简单起见）并且假设您将检测图像标记前面的平面。
我没有考虑旋转或类似的东西。当然，基于您提出的方案；它还假定您的图像将放在桌子或其他平面上。
无论如何，这是我的答案（希望它应该是不言自明的）：
import UIKit
import ARKit
//-----------------------
//MARK: ARSCNViewDelegate
//-----------------------
extension ViewController: ARSCNViewDelegate{
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
//1. If We Have Detected Our ImageTarget Then Create A Plane To Visualize It
if let currentImageAnchor = anchor as? ARImageAnchor {
createReferenceImagePlaneForNode(currentImageAnchor, node: node)
allowTracking = true
}
//2. If We Have Detected A Horizontal Plane Then Create One
if let currentPlaneAnchor = anchor as? ARPlaneAnchor{
if planeNode == nil && !createdModel{ createReferencePlaneForNode(currentPlaneAnchor, node: node) }
}
}
func renderer(_ renderer: SCNSceneRenderer, didUpdate node: SCNNode, for anchor: ARAnchor) {
//1. Check To See Whether An ARPlaneAnchor Has Been Updated
guard let anchor = anchor as? ARPlaneAnchor,
//2. Check It Is Our PlaneNode
let existingPlane = planeNode,
//3. Get The Geometry Of The PlaneNode
let planeGeometry = existingPlane.geometry as? SCNPlane else { return }
//4. Adjust It's Size & Positions
planeGeometry.width = CGFloat(anchor.extent.x)
planeGeometry.height = CGFloat(anchor.extent.z)
planeNode?.position = SCNVector3Make(anchor.center.x, 0.01, anchor.center.z)
}
func renderer(_ renderer: SCNSceneRenderer, updateAtTime time: TimeInterval) {
//1. Detect The Intersection Of The ARPlaneAnchor & ARImageAncho
if allowTracking { detectIntersetionOfImageTarget() }
}
}
//---------------------------------------
//MARK: Model Generation & Identification
//---------------------------------------
extension ViewController {
/// Detects If We Have Intersected A Valid Image Target
func detectIntersetionOfImageTarget(){
//If We Havent Created Our Model Then Check To See If We Have Detected An Existing Plane
if !createdModel{
//a. Perform A HitTest On The Center Of The Screen For AnyExisting Planes
guard let planeHitTest = self.augmentedRealityView.hitTest(screenCenter, types: .existingPlaneUsingExtent).first,
let planeAnchor = planeHitTest.anchor as? ARPlaneAnchor else { return }
//b. Get The Transform Of The ARPlane Anchor
let x = planeAnchor.transform.columns.3.x
let y = planeAnchor.transform.columns.3.y
let z = planeAnchor.transform.columns.3.z
//b. Create The Anchors Vector
let anchorVector = SCNVector3(x,y, z)
//Perform Another HitTest From The ImageAnchor Vector To The Anchors Vector
if let _ = self.augmentedRealityView.scene.rootNode.hitTestWithSegment(from: imageAnchorVector, to: anchorVector, options: nil).first?.node {
//a. If We Havent Created The Model Then Place It As Soon As An Intersection Occures
if createdModel == false{
//b. Load The Model
loadModelAtVector(SCNVector3(imageAnchorVector.x, y, imageAnchorVector.z))
createdModel = true
planeNode?.removeFromParentNode()
}
}
}
}
}
class ViewController: UIViewController {
//1. Reference To Our ImageTarget Bundle
let AR_BUNDLE = "AR Resources"
//2. Vector To Store The Position Of Our Detected Image
var imageAnchorVector: SCNVector3!
//3. Variables To Allow Tracking & To Determine Whether Our Model Has Been Placed
var allowTracking = false
var createdModel = false
//4. Create A Reference To Our ARSCNView In Our Storyboard Which Displays The Camera Feed
@IBOutlet weak var augmentedRealityView: ARSCNView!
//5. Create Our ARWorld Tracking Configuration
let configuration = ARWorldTrackingConfiguration()
//6. Create Our Session
let augmentedRealitySession = ARSession()
//7. ARReference Images
lazy var staticReferenceImages: Set<ARReferenceImage> = {
let images = ARReferenceImage.referenceImages(inGroupNamed: AR_BUNDLE, bundle: nil)
return images!
}()
//8. Scrren Center Reference
var screenCenter: CGPoint!
//9. PlaneNode
var planeNode: SCNNode?
//--------------------
//MARK: View LifeCycle
//--------------------
override func viewDidLoad() {
super.viewDidLoad()
//1. Get Reference To The Center Of The Screen For RayCasting
DispatchQueue.main.async { self.screenCenter = CGPoint(x: self.view.bounds.width/2, y: self.view.bounds.height/2) }
//2. Setup Our ARSession
setupARSessionWithStaticImages()
}
override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() }
//---------------------------------
//MARK: ARImageAnchor Vizualization
//---------------------------------
/// Creates An SCNPlane For Visualizing The Detected ARImageAnchor
///
/// - Parameters:
/// - imageAnchor: ARImageAnchor
/// - node: SCNNode
func createReferenceImagePlaneForNode(_ imageAnchor: ARImageAnchor, node: SCNNode){
//1. Get The Targets Width & Height
let width = imageAnchor.referenceImage.physicalSize.width
let height = imageAnchor.referenceImage.physicalSize.height
//2. Create A Plane Geometry To Cover The ARImageAnchor
let planeNode = SCNNode()
let planeGeometry = SCNPlane(width: width, height: height)
planeGeometry.firstMaterial?.diffuse.contents = UIColor.white
planeNode.opacity = 0.5
planeNode.geometry = planeGeometry
//3. Rotate The PlaneNode To Horizontal
planeNode.eulerAngles.x = -.pi/2
//4. The Node Is Centered In The Anchor (0,0,0)
node.addChildNode(planeNode)
//5. Store The Vector Of The ARImageAnchor
imageAnchorVector = SCNVector3(imageAnchor.transform.columns.3.x, imageAnchor.transform.columns.3.y, imageAnchor.transform.columns.3.z)
let fadeOutAction = SCNAction.fadeOut(duration: 5)
planeNode.runAction(fadeOutAction)
}
//-------------------------
//MARK: Plane Visualization
//-------------------------
/// Creates An SCNPlane For Visualizing The Detected ARAnchor
///
/// - Parameters:
/// - imageAnchor: ARAnchor
/// - node: SCNNode
func createReferencePlaneForNode(_ anchor: ARPlaneAnchor, node: SCNNode){
//1. Get The Anchors Width & Height
let width = CGFloat(anchor.extent.x)
let height = CGFloat(anchor.extent.z)
//2. Create A Plane Geometry To Cover The ARImageAnchor
planeNode = SCNNode()
let planeGeometry = SCNPlane(width: width, height: height)
planeGeometry.firstMaterial?.diffuse.contents = UIColor.white
planeNode?.opacity = 0.5
planeNode?.geometry = planeGeometry
//3. Rotate The PlaneNode To Horizontal
planeNode?.eulerAngles.x = -.pi/2
//4. The Node Is Centered In The Anchor (0,0,0)
node.addChildNode(planeNode!)
}
//-------------------
//MARK: Model Loading
//-------------------
/// Loads Our Model Based On The Resulting Vector Of Our ARAnchor
///
/// - Parameter worldVector: SCNVector3
func loadModelAtVector(_ worldVector: SCNVector3) {
let modelPath = "ARModels.scnassets/Scatterbug.scn"
//1. Get The Reference To Our SCNScene & Get The Model Root Node
guard let model = SCNScene(named: modelPath),
let pokemonModel = model.rootNode.childNode(withName: "RootNode", recursively: false) else { return }
//2.Add It To Our SCNView
augmentedRealityView.scene.rootNode.addChildNode(pokemonModel)
//3. Scale The Scatterbug
pokemonModel.scale = SCNVector3(0.003, 0.003, 0.003)
pokemonModel.position = worldVector
augmentedRealityView.scene.rootNode.addChildNode(pokemonModel)
}
//---------------
//MARK: ARSession
//---------------
/// Sets Up The AR Session With Static Or Dynamic AEImages
func setupARSessionWithStaticImages(){
//1. Set Our Configuration
configuration.detectionImages = staticReferenceImages
configuration.planeDetection = .horizontal
//2. Run The Configuration
augmentedRealitySession.run(configuration, options: [.resetTracking, .removeExistingAnchors])
//3. Set The Session & Delegate
augmentedRealityView?.session = augmentedRealitySession
self.augmentedRealityView?.delegate = self
}
}
希望它能为您指明正确的方向...
我正在使用 ARKit（带有 Scene Kit）并试图找到一种方法来获取 ARReference 图像和 Horizontal ARPlaneDetection 之间的交集，以便在检测到的图像正前方的表面上显示 3D 角色，例如, 在红圈内生成见下图
目前我能够让角色在检测到的图像前面生成，但是，角色漂浮在空中而不是站在表面上。
let realWorldPositon = SCNVector3Make(anchor.transform.columns.3.x, anchor.transform.columns.3.y, anchor.transform.columns.3.z)
let hitTest = self.sceneView.scene.rootNode.hitTestWithSegment(from: self.sceneView.scene.rootNode.worldPosition, to: realWorldPositon, options: nil)
overlayNode.position = SCNVector3Make((hitTest.first?.worldCoordinates.x)!, 0, (hitTest.first?.worldCoordinates.z)!)
self.sceneView.scene.rootNode.addChildNode(overlayNode)
如有任何帮助，我们将不胜感激，谢谢！
我认为您使用 hitTestWithSegment 函数来检测 ARImageAnchor 和 ARPlaneAnchor 之间的交集是正确的。
我没有试图解释我尝试回答的每一步，而是提供了完整注释的代码，因此它应该是相当自我解释的。
我的例子运行得相当好（虽然它肯定不完美）并且肯定需要一些调整。
例如，您需要更准确地确定从 ARReferenceImage 到 ARPlaneAnchor 等的距离
我可以将模型（口袋妖怪）放置在正确的水平并且非常靠近 ARReferenceImage 的前面，尽管它需要调整。
话虽如此，我认为这将是您开始精炼代码并获得更准确结果的一个相当好的基础。
然而，值得注意的是，我刚刚启用了一个 ARPlaneAnchor 来检测（只是为了简单起见）并且假设您将检测图像标记前面的平面。
我没有考虑旋转或类似的东西。当然，基于您提出的方案；它还假定您的图像将放在桌子或其他平面上。
无论如何，这是我的答案（希望它应该是不言自明的）：
import UIKit
import ARKit
//-----------------------
//MARK: ARSCNViewDelegate
//-----------------------
extension ViewController: ARSCNViewDelegate{
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
//1. If We Have Detected Our ImageTarget Then Create A Plane To Visualize It
if let currentImageAnchor = anchor as? ARImageAnchor {
createReferenceImagePlaneForNode(currentImageAnchor, node: node)
allowTracking = true
}
//2. If We Have Detected A Horizontal Plane Then Create One
if let currentPlaneAnchor = anchor as? ARPlaneAnchor{
if planeNode == nil && !createdModel{ createReferencePlaneForNode(currentPlaneAnchor, node: node) }
}
}
func renderer(_ renderer: SCNSceneRenderer, didUpdate node: SCNNode, for anchor: ARAnchor) {
//1. Check To See Whether An ARPlaneAnchor Has Been Updated
guard let anchor = anchor as? ARPlaneAnchor,
//2. Check It Is Our PlaneNode
let existingPlane = planeNode,
//3. Get The Geometry Of The PlaneNode
let planeGeometry = existingPlane.geometry as? SCNPlane else { return }
//4. Adjust It's Size & Positions
planeGeometry.width = CGFloat(anchor.extent.x)
planeGeometry.height = CGFloat(anchor.extent.z)
planeNode?.position = SCNVector3Make(anchor.center.x, 0.01, anchor.center.z)
}
func renderer(_ renderer: SCNSceneRenderer, updateAtTime time: TimeInterval) {
//1. Detect The Intersection Of The ARPlaneAnchor & ARImageAncho
if allowTracking { detectIntersetionOfImageTarget() }
}
}
//---------------------------------------
//MARK: Model Generation & Identification
//---------------------------------------
extension ViewController {
/// Detects If We Have Intersected A Valid Image Target
func detectIntersetionOfImageTarget(){
//If We Havent Created Our Model Then Check To See If We Have Detected An Existing Plane
if !createdModel{
//a. Perform A HitTest On The Center Of The Screen For AnyExisting Planes
guard let planeHitTest = self.augmentedRealityView.hitTest(screenCenter, types: .existingPlaneUsingExtent).first,
let planeAnchor = planeHitTest.anchor as? ARPlaneAnchor else { return }
//b. Get The Transform Of The ARPlane Anchor
let x = planeAnchor.transform.columns.3.x
let y = planeAnchor.transform.columns.3.y
let z = planeAnchor.transform.columns.3.z
//b. Create The Anchors Vector
let anchorVector = SCNVector3(x,y, z)
//Perform Another HitTest From The ImageAnchor Vector To The Anchors Vector
if let _ = self.augmentedRealityView.scene.rootNode.hitTestWithSegment(from: imageAnchorVector, to: anchorVector, options: nil).first?.node {
//a. If We Havent Created The Model Then Place It As Soon As An Intersection Occures
if createdModel == false{
//b. Load The Model
loadModelAtVector(SCNVector3(imageAnchorVector.x, y, imageAnchorVector.z))
createdModel = true
planeNode?.removeFromParentNode()
}
}
}
}
}
class ViewController: UIViewController {
//1. Reference To Our ImageTarget Bundle
let AR_BUNDLE = "AR Resources"
//2. Vector To Store The Position Of Our Detected Image
var imageAnchorVector: SCNVector3!
//3. Variables To Allow Tracking & To Determine Whether Our Model Has Been Placed
var allowTracking = false
var createdModel = false
//4. Create A Reference To Our ARSCNView In Our Storyboard Which Displays The Camera Feed
@IBOutlet weak var augmentedRealityView: ARSCNView!
//5. Create Our ARWorld Tracking Configuration
let configuration = ARWorldTrackingConfiguration()
//6. Create Our Session
let augmentedRealitySession = ARSession()
//7. ARReference Images
lazy var staticReferenceImages: Set<ARReferenceImage> = {
let images = ARReferenceImage.referenceImages(inGroupNamed: AR_BUNDLE, bundle: nil)
return images!
}()
//8. Scrren Center Reference
var screenCenter: CGPoint!
//9. PlaneNode
var planeNode: SCNNode?
//--------------------
//MARK: View LifeCycle
//--------------------
override func viewDidLoad() {
super.viewDidLoad()
//1. Get Reference To The Center Of The Screen For RayCasting
DispatchQueue.main.async { self.screenCenter = CGPoint(x: self.view.bounds.width/2, y: self.view.bounds.height/2) }
//2. Setup Our ARSession
setupARSessionWithStaticImages()
}
override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() }
//---------------------------------
//MARK: ARImageAnchor Vizualization
//---------------------------------
/// Creates An SCNPlane For Visualizing The Detected ARImageAnchor
///
/// - Parameters:
/// - imageAnchor: ARImageAnchor
/// - node: SCNNode
func createReferenceImagePlaneForNode(_ imageAnchor: ARImageAnchor, node: SCNNode){
//1. Get The Targets Width & Height
let width = imageAnchor.referenceImage.physicalSize.width
let height = imageAnchor.referenceImage.physicalSize.height
//2. Create A Plane Geometry To Cover The ARImageAnchor
let planeNode = SCNNode()
let planeGeometry = SCNPlane(width: width, height: height)
planeGeometry.firstMaterial?.diffuse.contents = UIColor.white
planeNode.opacity = 0.5
planeNode.geometry = planeGeometry
//3. Rotate The PlaneNode To Horizontal
planeNode.eulerAngles.x = -.pi/2
//4. The Node Is Centered In The Anchor (0,0,0)
node.addChildNode(planeNode)
//5. Store The Vector Of The ARImageAnchor
imageAnchorVector = SCNVector3(imageAnchor.transform.columns.3.x, imageAnchor.transform.columns.3.y, imageAnchor.transform.columns.3.z)
let fadeOutAction = SCNAction.fadeOut(duration: 5)
planeNode.runAction(fadeOutAction)
}
//-------------------------
//MARK: Plane Visualization
//-------------------------
/// Creates An SCNPlane For Visualizing The Detected ARAnchor
///
/// - Parameters:
/// - imageAnchor: ARAnchor
/// - node: SCNNode
func createReferencePlaneForNode(_ anchor: ARPlaneAnchor, node: SCNNode){
//1. Get The Anchors Width & Height
let width = CGFloat(anchor.extent.x)
let height = CGFloat(anchor.extent.z)
//2. Create A Plane Geometry To Cover The ARImageAnchor
planeNode = SCNNode()
let planeGeometry = SCNPlane(width: width, height: height)
planeGeometry.firstMaterial?.diffuse.contents = UIColor.white
planeNode?.opacity = 0.5
planeNode?.geometry = planeGeometry
//3. Rotate The PlaneNode To Horizontal
planeNode?.eulerAngles.x = -.pi/2
//4. The Node Is Centered In The Anchor (0,0,0)
node.addChildNode(planeNode!)
}
//-------------------
//MARK: Model Loading
//-------------------
/// Loads Our Model Based On The Resulting Vector Of Our ARAnchor
///
/// - Parameter worldVector: SCNVector3
func loadModelAtVector(_ worldVector: SCNVector3) {
let modelPath = "ARModels.scnassets/Scatterbug.scn"
//1. Get The Reference To Our SCNScene & Get The Model Root Node
guard let model = SCNScene(named: modelPath),
let pokemonModel = model.rootNode.childNode(withName: "RootNode", recursively: false) else { return }
//2.Add It To Our SCNView
augmentedRealityView.scene.rootNode.addChildNode(pokemonModel)
//3. Scale The Scatterbug
pokemonModel.scale = SCNVector3(0.003, 0.003, 0.003)
pokemonModel.position = worldVector
augmentedRealityView.scene.rootNode.addChildNode(pokemonModel)
}
//---------------
//MARK: ARSession
//---------------
/// Sets Up The AR Session With Static Or Dynamic AEImages
func setupARSessionWithStaticImages(){
//1. Set Our Configuration
configuration.detectionImages = staticReferenceImages
configuration.planeDetection = .horizontal
//2. Run The Configuration
augmentedRealitySession.run(configuration, options: [.resetTracking, .removeExistingAnchors])
//3. Set The Session & Delegate
augmentedRealityView?.session = augmentedRealitySession
self.augmentedRealityView?.delegate = self
}
}
希望它能为您指明正确的方向...