我在 SceneKit 中遇到锥体和金字塔的物理问题,物理体似乎在地面上盘旋。如果我用一个 SCNBox 替换它,那么没有问题。它在较小的尺度上更明显,其中地面上的空间相对于节点的尺寸要大得多。这几乎就像有一个固定的偏移量。无论锥体是否具有面向地板的平坦侧面或点,都会发生这种情况。
下面的代码和屏幕截图(链接),示例创建并在新创建的 Xcode SceneKit 项目中运行。 (Xcode 9,swift 4 但在 Xcode 和 swift 3 的早期版本中也存在问题)。
import UIKit
import QuartzCore
import SceneKit
var scnView: SCNView!
var scnScene: SCNScene!
var cameraNode: SCNNode!
let universalScale: Float = 1 / 40
enter image description hereclass GameViewController: UIViewController, SCNSceneRendererDelegate {
override func viewDidLoad() {
super.viewDidLoad()
setupView()
setupScene()
setupCamera()
spawnFloor()
spawnShape()
}
func setupView() {
scnView = self.view as! SCNView
scnView.showsStatistics = false
scnView.allowsCameraControl = true
scnView.autoenablesDefaultLighting = true
scnView.debugOptions = .showPhysicsShapes
scnView.showsStatistics = true
scnView.delegate = self
}
func setupScene() {
scnScene = SCNScene()
scnView.scene = scnScene
}
func setupCamera() {
cameraNode = SCNNode()
cameraNode.camera = SCNCamera()
cameraNode.position = SCNVector3(x: 0 * universalScale, y: 50 * universalScale, z: 50 * universalScale)
cameraNode.rotation = SCNVector4Make(1, 0, 0, -Float(Double.pi)/4)
scnScene.rootNode.addChildNode(cameraNode)
}
func spawnFloor() {
let floor = SCNFloor()
floor.reflectivity = 0.5
let material = floor.firstMaterial
material?.diffuse.contents = UIColor.gray
let floorNode = SCNNode(geometry: floor)
floorNode.physicsBody = SCNPhysicsBody(type: .static, shape: nil)
scnScene.rootNode.addChildNode(floorNode)
}
var shapeNode: SCNNode?
func spawnShape(){
let cone = SCNCone(topRadius: 0, bottomRadius:CGFloat(1 * universalScale), height: CGFloat(universalScale * 2))
let coneShape = SCNPhysicsShape(geometry: cone, options: nil)
let coneNode = SCNNode(geometry: cone)
coneNode.physicsBody = SCNPhysicsBody(type: .dynamic, shape: coneShape)
coneNode.position = SCNVector3(0, -coneNode.boundingBox.min.y + 20*universalScale, 0)
scnScene.rootNode.addChildNode(coneNode)
shapeNode = coneNode
}
func renderer(_ renderer: SCNSceneRenderer, didRenderScene scene: SCNScene, atTime time: TimeInterval) {
if shapeNode != nil{
print(shapeNode!.presentation.position)
print(shapeNode!.boundingBox.min)
}
}
}