在SCNLight中添加SK3DNode

Question

我正在SKScene中创建一个SKScene

let ball: SK3DNode = {
    let scnScene = SCNScene()
    let ballGeometry = SCNSphere(radius: 200)
    let ballNode = SCNNode(geometry: ballGeometry)
    ballNode.position = SCNVector3(0, 0, 0)

    let material = SCNMaterial()
    material.diffuse.contents = UIImage(named: "wall")
    ballGeometry.materials = [material]

    let light = SCNLight()
    light.type = .omni
    light.color = UIColor.white
    let lightNode = SCNNode()
    lightNode.light = light

    scnScene.rootNode.addChildNode(ballNode)
    scnScene.rootNode.addChildNode(lightNode)
    let node = SK3DNode(viewportSize: CGSize(width: 1000, height: 1000))
    node.scnScene = scnScene
    node.autoenablesDefaultLighting = false
    return node
}()

然而，球体呈现黑色。不管有没有材料都试过。我遗漏了什么吗？

Answer 1

球体是手动放置在(0, 0, 0)上的，光线也是如此(默认值)。这意味着光被放置在球体内。这意味着球体的表面远离光源，因此不会发光。