ARKit-如何在另一個SCNNode中包含SCNText（語音氣泡）

Question

我正在嘗試在ARKit的氣泡中創建帶有簡單文本的報價生成器。

我可以用文本顯示氣泡，但是文本總是從中間開始，並在氣泡之外溢出。

任何將其對齊在氣泡左上方並包裹在氣泡內的幫助將不勝感激。

結果

類

class SpeechBubbleNode: SCNNode {
    private let textNode = TextNode()

    var string: String? {
        didSet {
            textNode.string = string
        }
    }

    override init() {
        super.init()

        // Speech Bubble
        let plane = SCNPlane(width: 200.0, height: 100.0)
        plane.cornerRadius = 4.0
        plane.firstMaterial?.isDoubleSided = true
        geometry = plane

        // Text Node
        textNode.position = SCNVector3(position.x, position.y, position.z + 1.0)
//        textNode.position = convertPosition(SCNVector3(0.0, 0.0, 1.0), to: textNode)
//        textNode.position = SCNVector3(0.0, 0.0, position.z + 1.0)
        addChildNode(textNode)
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }
}

class TextNode: SCNNode {
    private let textGeometry = SCNText()

    var string: String? {
        didSet {
            updateTextContainerFrame()
            textGeometry.string = string
        }
    }

    override init() {
        super.init()

        textGeometry.truncationMode = CATextLayerTruncationMode.middle.rawValue
        textGeometry.isWrapped = true
        textGeometry.alignmentMode = CATextLayerAlignmentMode.left.rawValue

        let blackMaterial = SCNMaterial()
        blackMaterial.diffuse.contents = UIColor.black
        blackMaterial.locksAmbientWithDiffuse = true
        textGeometry.materials = [blackMaterial]

        geometry = textGeometry
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }

    private func updateTextContainerFrame() {
        let (min, max) = boundingBox
        let width = CGFloat(max.x - min.x)
        let height = CGFloat(max.y - min.y)
        print("width :",max.x - min.x,"height :",max.y - min.y,"depth :",max.z - min.z)
        textGeometry.containerFrame = CGRect(x: 0.0, y: 0.0, width: width, height: height)
//        textGeometry.containerFrame = CGRect(origin: .zero, size: CGSize(width: 1.0, height: 1.0))
    }
}

履行

private func makeSpeechBubbleNode(forBobbleheadNode bobbleheadNode: BobbleheadNode) {
    let node = SpeechBubbleNode()
    node.position = sceneView.scene.rootNode.convertPosition(bobbleheadNode.position, to: node)
    node.scale = SCNVector3(0.002, 0.002, 0.002)

    sceneView.scene.rootNode.addChildNode(speechBubbleNode)
    self.speechBubbleNode = speechBubbleNode

    speechBubbleNode.string = "Some random string that could be long and should wrap within speech bubble"
}

Answer 1

我遇到了同樣的問題，終於解決了如下問題：

• 創建一個SCNText並將其作為幾何添加到SCNNode：

   let string = "Coverin text with a plane :)" let text = SCNText(string: string, extrusionDepth: 0.1) text.font = UIFont.systemFont(ofSize: 1) text.flatness = 0.005 let textNode = SCNNode(geometry: text) let fontScale: Float = 0.01 textNode.scale = SCNVector3(fontScale, fontScale, fontScale) 

• 將文本數據透視表從左下到中心進行協調 ：

   let (min, max) = (text.boundingBox.min, text.boundingBox.max) let dx = min.x + 0.5 * (max.x - min.x) let dy = min.y + 0.5 * (max.y - min.y) let dz = min.z + 0.5 * (max.z - min.z) textNode.pivot = SCNMatrix4MakeTranslation(dx, dy, dz) 

• 創建一個PlaneNode並將textNode添加為PlaneNode的childNode：

   let width = (max.x - min.x) * fontScale let height = (max.y - min.y) * fontScale let plane = SCNPlane(width: CGFloat(width), height: CGFloat(height)) let planeNode = SCNNode(geometry: plane) planeNode.geometry?.firstMaterial?.diffuse.contents = UIColor.green.withAlphaComponent(0.5) planeNode.geometry?.firstMaterial?.isDoubleSided = true planeNode.position = textNode.position textNode.eulerAngles = planeNode.eulerAngles planeNode.addChildNode(textNode) 

• 最后，將PlaneNode添加到sceneView中：

   sceneView.scene.rootNode.addChildNode(planeNode) 

結果是：

Answer 2

如果您只需要在文本后面添加一個白框，則可以通過在渲染器函數中執行此操作來實現：

func renderer(_ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> SCNNode? {

        let node = SCNNode()

        ............

        let testPlane = SCNPlane(width: someWidth, height: someHeight)


        let testScene = SKScene(size: CGSize(width: 900, height: 900))
        testScene.backgroundColor = UIColor.white

        let str = SKLabelNode(text: "This is just a test")
        str.color = UIColor.black
        str.fontColor = UIColor.black
        str.fontSize = 45.5

        str.position = CGPoint(x: stuff.size.width / 2,
                                 y: stuff.size.height / 2)
        testScene.addChild(str)

        testPlane.firstMaterial?.diffuse.contents = testScene
        testPlane.firstMaterial?.isDoubleSided = true
        testPlane.firstMaterial?.diffuse.contentsTransform = SCNMatrix4Translate(SCNMatrix4MakeScale(1, -1, 1), 0, 1, 0)

        let testNode = SCNNode(geometry: testPlane)


        testNode.eulerAngles.x = -.pi / 2
        testNode.position = SCNVector3Make(0.0,0.0,0.0)

        node.addChildNode(testNode)


}