3

我正在尝试在 ARKit 的语音气泡中创建一个带有简单文本的报价生成器。

我可以用文字显示对话泡泡，但文字总是从中间开始并溢出对话泡泡之外。

任何帮助使其在语音气泡的左上角对齐并包裹在语音气泡中将不胜感激。

结果

在此处输入图像描述

课程

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))
    }
}

执行

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"
}
4

2 回答 2

5

我有同样的问题，最后我解决了如下：

  • 创建一个 SCNText 并将其作为几何图形添加到 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)

  • 将文本枢轴形式从左下角协调到中心：

    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)

  • 创建一个 PlaneNode 并将 textNode 添加为 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)

  • 最后将PlaneNode添加到sceneView：

    sceneView.scene.rootNode.addChildNode(planeNode)

这就是结果：

在此处输入图像描述

于 2018-08-22T07:39:25.383 回答
1

如果您只需要文本后面的白框，我可以通过在渲染器函数中执行此操作来实现：

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)


}
于 2018-08-15T22:02:54.067 回答