如何指向和定位 arkit 文本
how to point and position arkit text
下面的代码只是将文本随机放置在视图中。我希望用户能够按照他们选择的方式指向并定位文本。
鉴于您并不完全清楚您想做什么，我将根据我对您问题的解释提供答案，我认为这是在询问用户如何将 SCNNode 与SCNTextGeometry 在用户指定的位置，例如（点击位置），然后定位或与之交互。
下面的代码是一个非常粗略的示例，它允许用户在 tapLocation 处放置一个 SCNNode 和一个 SCNTextGeometry。
然后用户可以使用 UIPinchGestureRecognizer 缩放它或使用 UIRotationGestureRecognizer 旋转它。
您需要在 tapGestureRecognizer 中设置 currentNode，但它应该会为您指明正确的方向。
所有代码都有完整的注释，因此应该很有意义：
class ViewController: UIViewController {
//1. Create A Reference To Our ARSCNView In Our Storyboard Which Displays The Camera Feed
@IBOutlet weak var augmentedRealityView: ARSCNView!
//2. Create Our ARWorld Tracking Configuration
let configuration = ARWorldTrackingConfiguration()
//3. Create Our Session
let augmentedRealitySession = ARSession()
//4. Create A Variable To Store The Current Nodes Rotation Around It's Y-Axis
var currentAngleY: Float = 0.0
var isRotating = false
var currentNode: SCNNode?
//--------------------
//MARK: View LifeCycle
//--------------------
override func viewDidLoad() {
super.viewDidLoad()
//1. Run The ARSession
augmentedRealityView.session = augmentedRealitySession
augmentedRealitySession.run(configuration, options: [.resetTracking, .removeExistingAnchors])
//2. Add A UIPinchGestureRecognizer So We Can Scale Our TextNode
let scaleGesture = UIPinchGestureRecognizer(target: self, action: #selector(scaleCurrentNode(_:)))
self.view.addGestureRecognizer(scaleGesture)
//3. Add A Tap Gesture Recogizer So We Can Place Our TextNode
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(placeOrAssignNode(_:)))
self.view.addGestureRecognizer(tapGesture)
//4. Add A Rotation Gesture Recogizer So We Can Rotate Our TextNode
let rotateGesture = UIRotationGestureRecognizer(target: self, action: #selector(rotateNode(_:)))
self.view.addGestureRecognizer(rotateGesture)
}
override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() }
//-----------------------
//MARK: Touch Interaction
//-----------------------
/// Performs An ARHitTest Or SCNHitTest So We Can Place Or Assign Our TextNode
///
/// - Parameter gesture: UITapGestureRecognizer
@objc func placeOrAssignNode(_ gesture: UITapGestureRecognizer){
//1. Get The Current Location Of The Tap
let currentTouchLocation = gesture.location(in: self.augmentedRealityView)
//2. If We Hit An SCNNode Set It As The Current Node So We Can Interact With It
if let nodeHitTest = self.augmentedRealityView.hitTest(currentTouchLocation, options: nil).first?.node{
currentNode = nodeHitTest
return
}
//3. Do An ARHitTest For Features Points So We Can Place An SCNNode
if let hitTest = self.augmentedRealityView.hitTest(currentTouchLocation, types: .featurePoint).first {
//4. Get The World Transform
let hitTestPosition = hitTest.worldTransform.columns.3
//5. Add The TestNode At The Desired Position
createTextFromPosition(SCNVector3(hitTestPosition.x, hitTestPosition.y, hitTestPosition.z))
return
}
}
//-------------------
//MARK: Node Creation
//-------------------
/// Creates An SCNNode With An SCNTextGeometry
///
/// - Parameter position: SCNVector3
func createTextFromPosition(_ position: SCNVector3){
let textNode = SCNNode()
//1. Create The Text Geometry With String & Depth Parameters
let textGeometry = SCNText(string: "Whosebug" , extrusionDepth: 1)
//2. Set The Font With Our Set Font & Size
textGeometry.font = UIFont(name: "Helvatica", size: 1)
//3. Set The Flatness To Zero (This Makes The Text Look Smoother)
textGeometry.flatness = 0
//4. Set The Colour Of The Text
textGeometry.firstMaterial?.diffuse.contents = UIColor.white
//5. Set The Text's Material
textNode.geometry = textGeometry
//6. Set The Pivot At The Center
let min = textNode.boundingBox.min
let max = textNode.boundingBox.max
textNode.pivot = SCNMatrix4MakeTranslation(
min.x + (max.x - min.x)/2,
min.y + (max.y - min.y)/2,
min.z + (max.z - min.z)/2
)
//7. Scale The Text So We Can Actually See It!
textNode.scale = SCNVector3(0.005, 0.005 , 0.005)
//8. Add It To The Hierachy & Position It
self.augmentedRealityView.scene.rootNode.addChildNode(textNode)
textNode.position = position
//9. Set It As The Current Node
currentNode = textNode
}
//-------------
//MARK: Scaling
//-------------
/// Scales The Currently Selected Node
///
/// - Parameter gesture: UIPinchGestureRecognizer
@objc func scaleCurrentNode(_ gesture: UIPinchGestureRecognizer) {
if !isRotating, let selectedNode = currentNode{
if gesture.state == .changed {
let pinchScaleX: CGFloat = gesture.scale * CGFloat((selectedNode.scale.x))
let pinchScaleY: CGFloat = gesture.scale * CGFloat((selectedNode.scale.y))
let pinchScaleZ: CGFloat = gesture.scale * CGFloat((selectedNode.scale.z))
selectedNode.scale = SCNVector3Make(Float(pinchScaleX), Float(pinchScaleY), Float(pinchScaleZ))
gesture.scale = 1
}
if gesture.state == .ended {}
}
}
//----------------
//MARK: Rotation
//----------------
/// Rotates The Currently Selected Node Around It's YAxis
///
/// - Parameter gesture: UIRotationGestureRecognizer
@objc func rotateNode(_ gesture: UIRotationGestureRecognizer){
if let selectedNode = currentNode{
//1. Get The Current Rotation From The Gesture
let rotation = Float(gesture.rotation)
//2. If The Gesture State Has Changed Set The Nodes EulerAngles.y
if gesture.state == .changed{
isRotating = true
selectedNode.eulerAngles.y = currentAngleY + rotation
}
//3. If The Gesture Has Ended Store The Last Angle Of The CurrentNode
if(gesture.state == .ended) {
currentAngleY = selectedNode.eulerAngles.y
isRotating = false
}
}
}
}
希望对您有所帮助...
下面的代码只是将文本随机放置在视图中。我希望用户能够按照他们选择的方式指向并定位文本。
鉴于您并不完全清楚您想做什么，我将根据我对您问题的解释提供答案，我认为这是在询问用户如何将 SCNNode 与SCNTextGeometry 在用户指定的位置，例如（点击位置），然后定位或与之交互。
下面的代码是一个非常粗略的示例，它允许用户在 tapLocation 处放置一个 SCNNode 和一个 SCNTextGeometry。
然后用户可以使用 UIPinchGestureRecognizer 缩放它或使用 UIRotationGestureRecognizer 旋转它。
您需要在 tapGestureRecognizer 中设置 currentNode，但它应该会为您指明正确的方向。
所有代码都有完整的注释，因此应该很有意义：
class ViewController: UIViewController {
//1. Create A Reference To Our ARSCNView In Our Storyboard Which Displays The Camera Feed
@IBOutlet weak var augmentedRealityView: ARSCNView!
//2. Create Our ARWorld Tracking Configuration
let configuration = ARWorldTrackingConfiguration()
//3. Create Our Session
let augmentedRealitySession = ARSession()
//4. Create A Variable To Store The Current Nodes Rotation Around It's Y-Axis
var currentAngleY: Float = 0.0
var isRotating = false
var currentNode: SCNNode?
//--------------------
//MARK: View LifeCycle
//--------------------
override func viewDidLoad() {
super.viewDidLoad()
//1. Run The ARSession
augmentedRealityView.session = augmentedRealitySession
augmentedRealitySession.run(configuration, options: [.resetTracking, .removeExistingAnchors])
//2. Add A UIPinchGestureRecognizer So We Can Scale Our TextNode
let scaleGesture = UIPinchGestureRecognizer(target: self, action: #selector(scaleCurrentNode(_:)))
self.view.addGestureRecognizer(scaleGesture)
//3. Add A Tap Gesture Recogizer So We Can Place Our TextNode
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(placeOrAssignNode(_:)))
self.view.addGestureRecognizer(tapGesture)
//4. Add A Rotation Gesture Recogizer So We Can Rotate Our TextNode
let rotateGesture = UIRotationGestureRecognizer(target: self, action: #selector(rotateNode(_:)))
self.view.addGestureRecognizer(rotateGesture)
}
override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() }
//-----------------------
//MARK: Touch Interaction
//-----------------------
/// Performs An ARHitTest Or SCNHitTest So We Can Place Or Assign Our TextNode
///
/// - Parameter gesture: UITapGestureRecognizer
@objc func placeOrAssignNode(_ gesture: UITapGestureRecognizer){
//1. Get The Current Location Of The Tap
let currentTouchLocation = gesture.location(in: self.augmentedRealityView)
//2. If We Hit An SCNNode Set It As The Current Node So We Can Interact With It
if let nodeHitTest = self.augmentedRealityView.hitTest(currentTouchLocation, options: nil).first?.node{
currentNode = nodeHitTest
return
}
//3. Do An ARHitTest For Features Points So We Can Place An SCNNode
if let hitTest = self.augmentedRealityView.hitTest(currentTouchLocation, types: .featurePoint).first {
//4. Get The World Transform
let hitTestPosition = hitTest.worldTransform.columns.3
//5. Add The TestNode At The Desired Position
createTextFromPosition(SCNVector3(hitTestPosition.x, hitTestPosition.y, hitTestPosition.z))
return
}
}
//-------------------
//MARK: Node Creation
//-------------------
/// Creates An SCNNode With An SCNTextGeometry
///
/// - Parameter position: SCNVector3
func createTextFromPosition(_ position: SCNVector3){
let textNode = SCNNode()
//1. Create The Text Geometry With String & Depth Parameters
let textGeometry = SCNText(string: "Whosebug" , extrusionDepth: 1)
//2. Set The Font With Our Set Font & Size
textGeometry.font = UIFont(name: "Helvatica", size: 1)
//3. Set The Flatness To Zero (This Makes The Text Look Smoother)
textGeometry.flatness = 0
//4. Set The Colour Of The Text
textGeometry.firstMaterial?.diffuse.contents = UIColor.white
//5. Set The Text's Material
textNode.geometry = textGeometry
//6. Set The Pivot At The Center
let min = textNode.boundingBox.min
let max = textNode.boundingBox.max
textNode.pivot = SCNMatrix4MakeTranslation(
min.x + (max.x - min.x)/2,
min.y + (max.y - min.y)/2,
min.z + (max.z - min.z)/2
)
//7. Scale The Text So We Can Actually See It!
textNode.scale = SCNVector3(0.005, 0.005 , 0.005)
//8. Add It To The Hierachy & Position It
self.augmentedRealityView.scene.rootNode.addChildNode(textNode)
textNode.position = position
//9. Set It As The Current Node
currentNode = textNode
}
//-------------
//MARK: Scaling
//-------------
/// Scales The Currently Selected Node
///
/// - Parameter gesture: UIPinchGestureRecognizer
@objc func scaleCurrentNode(_ gesture: UIPinchGestureRecognizer) {
if !isRotating, let selectedNode = currentNode{
if gesture.state == .changed {
let pinchScaleX: CGFloat = gesture.scale * CGFloat((selectedNode.scale.x))
let pinchScaleY: CGFloat = gesture.scale * CGFloat((selectedNode.scale.y))
let pinchScaleZ: CGFloat = gesture.scale * CGFloat((selectedNode.scale.z))
selectedNode.scale = SCNVector3Make(Float(pinchScaleX), Float(pinchScaleY), Float(pinchScaleZ))
gesture.scale = 1
}
if gesture.state == .ended {}
}
}
//----------------
//MARK: Rotation
//----------------
/// Rotates The Currently Selected Node Around It's YAxis
///
/// - Parameter gesture: UIRotationGestureRecognizer
@objc func rotateNode(_ gesture: UIRotationGestureRecognizer){
if let selectedNode = currentNode{
//1. Get The Current Rotation From The Gesture
let rotation = Float(gesture.rotation)
//2. If The Gesture State Has Changed Set The Nodes EulerAngles.y
if gesture.state == .changed{
isRotating = true
selectedNode.eulerAngles.y = currentAngleY + rotation
}
//3. If The Gesture Has Ended Store The Last Angle Of The CurrentNode
if(gesture.state == .ended) {
currentAngleY = selectedNode.eulerAngles.y
isRotating = false
}
}
}
}
希望对您有所帮助...