我一直在尝试将车身和车轮一起移动。我创建了增强现实项目，其中将汽车模型放置在水平面中，汽车由四个按钮(即加速，转向，倒车和制动)控制。左，右轿厢在加速和倒车时通过转向来控制。
实际上，现在我可以将3D汽车模型放置在水平面中，但不知道如何像车身一样向前和向后旋转车轮。
这是我一直试图放置3d对象的代码:
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
if let touch = touches.first {
// gives us the location of where we touched on the 2D screen.
let touchLocation = touch.location(in: sceneView)
// hitTest is performed to get the 3D coordinates corresponding to the 2D coordinates that we got from touching the screen.
// That 3d coordinate will only be considered when it is on the existing plane that we detected.
let results = sceneView.hitTest(touchLocation, types: .existingPlaneUsingExtent)
// if we have got some results using the hitTest then do this.
if let hitResult = results.first {
let boxScene = SCNScene(named: "art.scnassets/porsche.scn")!
if let boxNode = boxScene.rootNode.childNode(withName: "car", recursively: true) {
print("box:::\(boxNode.childNodes)")
boxNode.position = SCNVector3(x: hitResult.worldTransform.columns.3.x, y: hitResult.worldTransform.columns.3.y + 0.15, z: hitResult.worldTransform.columns.3.z)
// finally the box is added to the scene.
sceneView.scene.rootNode.addChildNode(boxNode)
}
}
}
}
检测水平面功能代码:
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
if anchor is ARPlaneAnchor {
// anchors can be of many types, as we are just dealing with horizontal plane detection we need to downcast anchor to ARPlaneAnchor
let planeAnchor = anchor as! ARPlaneAnchor
// creating a plane geometry with the help of dimentions we got using plane anchor.
let plane = SCNPlane(width: CGFloat(planeAnchor.extent.x), height: CGFloat(planeAnchor.extent.z))
// a node is basically a position.
let planeNode = SCNNode()
// setting the position of the plane geometry to the position we got using plane anchor.
planeNode.position = SCNVector3(x: planeAnchor.center.x, y: 0, z: planeAnchor.center.z)
// when a plane is created its created in xy plane instead of xz plane, so we need to rotate it along x axis.
planeNode.transform = SCNMatrix4MakeRotation(-Float.pi/2, 1, 0, 0)
//create a material object
let gridMaterial = SCNMaterial()
//setting the material as an image. A material can also be set to a color.
gridMaterial.diffuse.contents = UIImage(named: "art.scnassets/grid.png")
// assigning the material to the plane
plane.materials = [gridMaterial]
// assigning the position to the plane
planeNode.geometry = plane
//adding the plane node in our scene
node.addChildNode(planeNode)
}
else {
return
}
}
任何帮助，不胜感激!!!
最佳答案
这是一项非常全面的任务。
您应该将您的汽车作为SCNPhysicsVehicle子类。
SCNPhysicsVehicle是一种物理行为，可修改物理 body 使其表现得像汽车，摩托车或其他轮式车辆。
要制造车辆，请将SCNPhysicsBody对象指定为底盘，并将SCNPhysicsVehicleWheel对象数组指定为车轮。您可以为每个车轮定义诸如悬架和牵引力之类的物理特征，并关联场景中的节点以提供车轮的尺寸和视觉效果。构造车辆后，您可以在加速，制动和转向方面进行控制。
通用:https://developer.apple.com/documentation/scenekit/scnphysicsbody
对于车轮:https://developer.apple.com/documentation/scenekit/scnphysicsvehiclewheel
例子:
var vehicle = SCNPhysicsVehicle()
func createGround(planeAnchor: ARPlaneAnchor) -> SCNNode {
let ground = SCNNode(geometry: SCNPlane(width: CGFloat(planeAnchor.extent.x), height: CGFloat(CGFloat(planeAnchor.extent.z))))
ground.position = SCNVector3(planeAnchor.center.x,planeAnchor.center.y,planeAnchor.center.z)
ground.eulerAngles = SCNVector3(90.degreesToRadians, 0, 0)
let staticBody = SCNPhysicsBody.static() // it must be static
ground.physicsBody = staticBody
return ground
}
func setupCar() {
let scene = SCNScene(named: "YourScene.scn")
let chassis = (scene?.rootNode.childNode(withName: "chassis", recursively: true))! // Your chassis
let frontLeftWheel = chassis.childNode(withName: "frontLeftWheel", recursively: true)!
let frontRightWheel = chassis.childNode(withName: "frontRightWheel", recursively: true)!
let rearLeftWheel = chassis.childNode(withName: "rearLeftWheel", recursively: true)!
let rearRightWheel = chassis.childNode(withName: "rearRightWheel", recursively: true)!
// physic behavior for wheels
let v_frontLeftWheel = SCNPhysicsVehicleWheel(node: frontLeftWheel)
let v_frontRightWheel = SCNPhysicsVehicleWheel(node: frontRightWheel)
let v_rearRightWheel = SCNPhysicsVehicleWheel(node: rearLeftWheel)
let v_rearLeftWheel = SCNPhysicsVehicleWheel(node: rearRightWheel)
chassis.position = SCNVector(0,0,0) // insert your desired position
let body = SCNPhysicsBody(type: .dynamic, shape: SCNPhysicsShape(node: chassis, options: [SCNPhysicsShape.Option.keepAsCompound: true]))
body.mass = 1
chassis.physicsBody = body
self.vehicle = SCNPhysicsVehicle(chassisBody: chassis.physicsBody!, wheels: [v_rearRightWheel, v_rearLeftWheel, v_frontRightWheel, v_frontLeftWheel])
self.sceneView.scene.physicsWorld.addBehavior(self.vehicle)
self.sceneView.scene.rootNode.addChildNode(chassis)
}
func renderer(_ renderer: SCNSceneRenderer, didSimulatePhysicsAtTime time: TimeInterval) {
var engineForce: CGFloat = 5
var brakingForce: CGFloat = 0
// here you can manipulate your car steering angle
self.vehicle.setSteeringAngle(0, forWheelAt: 2)
self.vehicle.setSteeringAngle(0, forWheelAt: 3)
self.vehicle.applyEngineForce(engineForce, forWheelAt: 0)
self.vehicle.applyEngineForce(engineForce, forWheelAt: 1)
self.vehicle.applyBrakingForce(0, forWheelAt: 0)
self.vehicle.applyBrakingForce(0, forWheelAt: 1)
}
P.S.不要忘记添加到您的viewDidLoad()中:
self.sceneView.delegate = self
self.sceneView.scene?.physicsWorld.contactDelegate = self
P.P.S这只是一般性的想法，您必须进行一些研究并找到适合您具体情况的解决方案。
给您一个小提示，可以通过CoreMotion进行控制。
希望对您有所帮助!
关于ios - 如何快速地使车身沿着车轮移动？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/50346366/