swift - 使用 SKSpriteKit 和 Swift 4 通过触摸移动和旋转 Sprite

Question

我希望我的 Sprite “角色”在我四处移动时“跟随”我的手指移动和旋转。我让它工作得很好，但不知何故搞砸了。我不确定自己做了什么，但终生无法弄明白。

如有任何帮助，我们将不胜感激。我确定我只是忽略了一些愚蠢的事情。提前致谢。

标记

GameScene.swift

import SpriteKit
import GameplayKit

//MARK: ---------------Global Variables Section

var nodeType: String = String()

var characterNode = Character()
let characterImage: String = String("default_pose")
var characterTexture:SKTexture = SKTexture()
let characterSize: CGSize = CGSize(width: 64, height: 64)
let characterPosition: CGPoint = CGPoint(x: 0, y: 0)

var enemyNode = Enemy()
let enemyImage: String = String("blob1")
var enemyTexture = SKTexture()
let enemySize: CGSize = CGSize(width: 50, height: 50)
let enemyPosition: CGPoint = CGPoint(x: 150, y: 150)


class GameScene: SKScene, SKPhysicsContactDelegate {


    //MARK: --------------------Class Variables Section

    var affectedByGravity: Bool = false
    var dynamic: Bool = true
    var rotation: Bool = false

    var lastUpdateTime: CFTimeInterval = 0

    //MARK: --------------------DidMove to View Section

    override func didMove(to view: SKView) {

        var node = SKSpriteNode()

        node = addNode(NodeType: "Character")
        applyPhysics(physicsNode: node, nodeImage: characterImage, nodeSize: characterSize, nodeName: node.name!)
        node.zPosition = 10
        addChild(node)

        node = addNode(NodeType: "Enemy")
        applyPhysics(physicsNode: node, nodeImage: enemyImage, nodeSize: enemySize, nodeName: node.name!)
        node.zPosition = 9
        addChild(node)
    }


    //MARK: -----------------------Add Node Section

    func addNode(NodeType: String) -> SKSpriteNode {

        var node = SKSpriteNode()

        switch NodeType {

        case "Enemy":

            node = enemyNode.setupNode(nodeName: "Enemy", nodeImage: "blob1", nodeSize: enemySize, nodePosition: enemyPosition)

        default:
            node = characterNode.setupNode(nodeName: "Player", nodeImage: "default_pose", nodeSize: characterSize, nodePosition: characterPosition)
        }
        return node
    }

    //MARK: ------------------------Physics Section

    func applyPhysics(physicsNode: SKSpriteNode, nodeImage: String, nodeSize: CGSize, nodeName: String) {

        let nodeTexture: SKTexture = SKTexture(imageNamed: nodeImage)

        physicsNode.physicsBody = SKPhysicsBody(texture: nodeTexture, size: nodeSize)
        physicsNode.physicsBody?.isDynamic = dynamic
        physicsNode.physicsBody?.affectedByGravity = affectedByGravity
        physicsNode.physicsBody?.allowsRotation = rotation
        physicsNode.physicsBody?.categoryBitMask = 1
        physicsNode.physicsBody?.contactTestBitMask = 1
        physicsNode.physicsBody?.collisionBitMask = 1

    }

    //MARK: ------------------------Movement and Rotation Section

    func moveAndRotate(sprite: Character, toPosition position: CGPoint) {

        let angle = atan2(position.y - sprite.position.y, position.x - sprite.position.x)

        let rotateAction = SKAction.rotate(toAngle: angle - .pi / 2, duration: 0.05, shortestUnitArc:true)

        sprite.run(rotateAction)

        let offsetX = position.x - (sprite.position.x)
        let offsetY = position.y - (sprite.position.y)

        let normal = simd_normalize(simd_double2(x: Double(offsetX), y:Double(offsetY)))

        characterNode.velocity = CGVector(dx: CGFloat(normal.x) * sprite.movePointsPerSecond, dy: CGFloat(normal.y) * sprite.movePointsPerSecond)
    }

    //MARK: ----------------------Touches Section

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        if let touch = touches.first {
            let touchLocation = touch.location(in: self)
            characterNode.isMoving = true
            moveAndRotate(sprite: characterNode, toPosition: touchLocation)
        }
    }

    override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {

        if let touch = touches.first {
            let touchLocation = touch.location(in: self)
            moveAndRotate(sprite: characterNode, toPosition: touchLocation)
        }
    }

    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {

        characterNode.isMoving = false
    }


    //MARK: ------------------Update Section

    override func update(_ currentTime: TimeInterval) {

        let deltaTime = max(1.0/30, currentTime - lastUpdateTime)
        lastUpdateTime = currentTime

        update(character: characterNode, dt: deltaTime)
    }

    func update(character: Character, dt: CFTimeInterval) {
        if characterNode.isMoving == true {
            let newX = character.position.x + character.velocity.dx * CGFloat(dt)
            let newY = character.position.y + character.velocity.dy * CGFloat(dt)

            character.position = CGPoint(x: newX, y: newY)
        }
    }
}

字符.swift

import SpriteKit
import GameplayKit

class Character: SKSpriteNode {

    let movePointsPerSecond: CGFloat = 150.0
    var velocity = CGVector(dx: 0.0, dy: 0.0)
    var isMoving = false

    var node: SKSpriteNode = SKSpriteNode()

    func setupNode(nodeName: String, nodeImage: String, nodeSize: CGSize, nodePosition: CGPoint) -> SKSpriteNode {

        node = SKSpriteNode(imageNamed: nodeImage)
        node.name = nodeName
        node.position = nodePosition

        return node
    }
}

Answer 1

您的节点不会移动，因为您从未将 characterNode 分配给屏幕上的节点

   override func didMove(to view: SKView) {

        var node = SKSpriteNode()

        node = addNode(NodeType: "Character")
        applyPhysics(physicsNode: node, nodeImage: characterImage, nodeSize: characterSize, nodeName: node.name!)
        node.zPosition = 10
        addChild(node)
        characterNode = node //ADD THIS LINE
        node = addNode(NodeType: "Enemy")
        applyPhysics(physicsNode: node, nodeImage: enemyImage, nodeSize: enemySize, nodeName: node.name!)
        node.zPosition = 9
        addChild(node)
    }