Question

我有一个带有居中物体的简单场景，相机位于中心周围的虚拟球体上（灵感来自Rotate SCNCamera node looking at an object around an imaginary sphere）。

现在我希望能够用双指平移手势移动对象。只要我不先旋转相机，我的代码就可以正常工作。如果我首先将相机旋转180°（以便相机从后面看物体），那么移动的方向是错误的（这对我来说很有意义）。其他相机位置会变得更糟。但是，我无法找到如何将识别器的x / y平移转换或投影到与摄像机平行的平面。物体应该在手指下移动..

这是我场景的设置：

    let scene = SCNScene()

    //add camera
    let camera = SCNCamera()
    camera.usesOrthographicProjection = true
    camera.orthographicScale = 30
    camera.zNear = 1.0
    camera.zFar = 1000

    cameraNode = SCNNode()
    cameraNode.camera = camera
    cameraNode.position = SCNVector3(x: 0.0, y: 0.0, z: 50.0)

    cameraOrbit = SCNNode()
    cameraOrbit.addChildNode(cameraNode)

    scene.rootNode.addChildNode(cameraOrbit)

    boxNode.geometry = SCNBox(width: 10, height: 40, length: 10, chamferRadius: 0.2) 
    scene.rootNode.addChildNode(boxNode)

    let panMoveGestureRecognizer = UIPanGestureRecognizer(target: self, action:#selector(panMoveGesture))
    panMoveGestureRecognizer.minimumNumberOfTouches = 2
    sceneView.addGestureRecognizer(panMoveGestureRecognizer)

手势识别器代码：

func panMoveGesture(recognizer: UIPanGestureRecognizer) {

    //move
    let translation = recognizer.translation(in: self.view.superview)
    var newXMovement = -Float(translation.x) * 0.1
    var newYMovement = Float(translation.y) * 0.1

    switch recognizer.state {
        case .began:
            currentXMovement = cameraOrbit.position.x
            currentYMovement = cameraOrbit.position.y
        case .changed:
            newXMovement += currentXMovement
            newYMovement += currentYMovement

            cameraOrbit.position.x = newXMovement
            cameraOrbit.position.y = newYMovement
        case .ended:
            currentXMovement = newXMovement
            currentYMovement = newYMovement
        default: break
    }

}

请帮助; - ）

SceneKit基础：移动节点

0 个答案: