在我正在建造的游戏中，一个人应该抓住从天而降的球。如果球从屏幕上掉下来意味着他没有接球，那么场景应该改变为场景中的游戏。问题是，即使球不在屏幕下方，屏幕也会改变。但屏幕将变为空白屏幕，而不是GameOverScene()。
以下是GameScene() ...
//
// GameScene.swift
// catch balls
//
// Created by Ankith Udupa on 8/10/15.
// Copyright (c) 2015 UdupaLabs. All rights reserved.
//
import SpriteKit
var score = 0
var lossFlag = false
class GameScene: SKScene, SKPhysicsContactDelegate {
var person = SKSpriteNode(imageNamed: "guyLeft_1.png")
var left = true
let kScoreHudName = "scoreHud"
struct PhysicsCategory {
static let None : UInt32 = 0
static let All : UInt32 = UInt32.max
static let Ball : UInt32 = 0b1
static let Person: UInt32 = 0b10
}
override func didMoveToView(view: SKView) {
var content = false
//set up screen
setUpScreen()
//set up the physics
physicsWorld.gravity = CGVectorMake(0, 0)
physicsWorld.contactDelegate = self
//add ball
runAction(SKAction.repeatActionForever(
SKAction.sequence([
SKAction.runBlock(addBall),
SKAction.waitForDuration(1.0)
])
))
}
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
/* Called when a touch begins */
left = !left
}
override func update(currentTime: CFTimeInterval) {
/* Called before each frame is rendered */
if ((person.position.x > person.size.width/2) && (person.position.x < size.width-(person.size.width/2))){
if left {
var leftMove = SKAction.moveByX(5, y: 0, duration: 0.1)
person.runAction(leftMove)
}
if !left { // or use an if-else construct
var rightMove = SKAction.moveByX(-5, y: 0, duration: 0.1)
person.runAction(rightMove)
}
}
}
//random number gen functions
func random() -> CGFloat {
return CGFloat(Float(arc4random()) / 0xFFFFFFFF)
}
func random(#min: CGFloat, max: CGFloat) -> CGFloat {
return random() * (max - min) + min
}
//add ball function
func addBall(){
//create ball sprite
var ball = SKSpriteNode(imageNamed: "ball.png")
//create physics for ball
ball.physicsBody = SKPhysicsBody(rectangleOfSize: ball.size) // 1
ball.physicsBody?.dynamic = true // 2
ball.physicsBody?.categoryBitMask = PhysicsCategory.Ball // 3
ball.physicsBody?.contactTestBitMask = PhysicsCategory.Person // 4
ball.physicsBody?.collisionBitMask = PhysicsCategory.None // 5
//generate random postion along x axis for ball to spawn
let actualX = random(min:ball.size.width/2+1, max: size.width - ball.size.width/2-1)
//set balls positon
ball.position = CGPoint(x: actualX, y: size.height - ball.size.width/2)
//add ball to scene
addChild(ball)
//determine speed of ball
let actualDuration = random(min: CGFloat(3.0), max: CGFloat(5.0))
//create movement actions and run them
let actionMove = SKAction.moveTo(CGPoint(x:actualX, y: -ball.size.width/2), duration: NSTimeInterval(actualDuration))
let actionMoveDone = SKAction.removeFromParent()
let Loss = SKAction.runBlock() {
let reveal = SKTransition.crossFadeWithDuration(0.1)
let gameOverScene = GameOverScene()
self.view?.presentScene(GameOverScene(), transition: reveal)
}
ball.runAction(SKAction.sequence([actionMove, Loss, actionMoveDone]))
}
//setUpScreen
func setUpScreen(){
self.backgroundColor = SKColor.whiteColor()
var ground = SKShapeNode(rectOfSize: CGSizeMake(self.frame.size.width, self.frame.size.height * 0.2))
ground.position = CGPoint(x: self.frame.size.width / 2, y: self.frame.size.height * 0.1)
ground.fillColor = SKColor.blueColor()
self.addChild(ground)
person.position = CGPoint(x: self.frame.size.width / 2, y: self.frame.size.height * 0.2)
setUpPersonPhysics()
self.addChild(person)
}
//set up person physics
func setUpPersonPhysics(){
person.physicsBody = SKPhysicsBody(rectangleOfSize: person.size)
person.physicsBody?.dynamic = true
person.physicsBody?.categoryBitMask = PhysicsCategory.Person
person.physicsBody?.contactTestBitMask = PhysicsCategory.Ball
person.physicsBody?.collisionBitMask = PhysicsCategory.None
person.physicsBody?.usesPreciseCollisionDetection = true
}
func didBeginContact(contact: SKPhysicsContact) {
// 1
var firstBody: SKPhysicsBody
var secondBody: SKPhysicsBody
if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask {
firstBody = contact.bodyA
secondBody = contact.bodyB
}
else {
firstBody = contact.bodyB
secondBody = contact.bodyA
}
// 2
if ((firstBody.categoryBitMask & PhysicsCategory.Ball != 0) &&
(secondBody.categoryBitMask & PhysicsCategory.Person != 0)) {
personDidCollideWithBall(secondBody.node as! SKSpriteNode, ball: firstBody.node as! SKSpriteNode)
}
}
//called when person collides with ball
func personDidCollideWithBall(person:SKSpriteNode, ball:SKSpriteNode) {
println("hit")
ball.removeFromParent()
score++
}
}
以下是gameOverScene() ...
//
// gameOverScene.swift
// catch babies
//
// Created by Ankith Udupa on 8/12/15.
// Copyright (c) 2015 UdupaLabs. All rights reserved.
//
import Foundation
import SpriteKit
class GameOverScene: SKScene {
var message = "Game Over"
override func didMoveToView(view: SKView) {
self.backgroundColor = SKColor.whiteColor()
setUpTextOutPut()
}
func setUpTextOutPut(){
let gameOverLabel = SKLabelNode(fontNamed: "Superclarendon-Black")
gameOverLabel.text = message
gameOverLabel.fontSize = 40
gameOverLabel.fontColor = SKColor.orangeColor()
gameOverLabel.position = CGPoint(x: size.width/2, y: size.height/2)
addChild(gameOverLabel)
let scoreLabel = SKLabelNode(fontNamed: "Superclarendon-Black")
scoreLabel.text = "\(score)"
scoreLabel.fontSize = 40
scoreLabel.fontColor = SKColor.orangeColor()
scoreLabel.position = CGPoint(x: size.width/2, y: size.height/2-50)
addChild(scoreLabel)
}
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
}
}
答案 0 :(得分：0)
错误在于你的addBall方法，
//add ball function
func addBall(){
//create ball sprite
var ball = SKSpriteNode(imageNamed: "ball.png")
//create physics for ball
ball.physicsBody = SKPhysicsBody(rectangleOfSize: ball.size) // 1
ball.physicsBody?.dynamic = true // 2
ball.physicsBody?.categoryBitMask = PhysicsCategory.Ball // 3
ball.physicsBody?.contactTestBitMask = PhysicsCategory.Person // 4
ball.physicsBody?.collisionBitMask = PhysicsCategory.None // 5
//generate random postion along x axis for ball to spawn
let actualX = random(min:ball.size.width/2+1, max: size.width - ball.size.width/2-1)
//set balls positon
ball.position = CGPoint(x: actualX, y: size.height - ball.size.width/2)
//add ball to scene
addChild(ball)
//determine speed of ball
let actualDuration = random(min: CGFloat(3.0), max: CGFloat(5.0))
//create movement actions and run them
let actionMove = SKAction.moveTo(CGPoint(x:actualX, y: -ball.size.width/2), duration: NSTimeInterval(actualDuration))
let actionMoveDone = SKAction.removeFromParent()
let Loss = SKAction.runBlock() {
let reveal = SKTransition.crossFadeWithDuration(0.1)
let gameOverScene = GameOverScene()
self.view?.presentScene(GameOverScene(), transition: reveal)
}
ball.runAction(SKAction.sequence([actionMove, Loss, actionMoveDone]))
}
如果正确查看方法，则要求将序列运行到sprite并在runBlock内部移动到另一个场景。你需要检查球是否在这个区域内的界外，然后才能在场景中展示你的游戏吗？
应该是这样的，
let Loss = SKAction.runBlock() {
if ball.position.x > self.size.width + ball.frame.size.width * 0.5 || ball.position.y < ball.frame.size.height * 0.5 {
let reveal = SKTransition.crossFadeWithDuration(0.1)
let gameOverScene = GameOverScene()
self.view?.presentScene(GameOverScene(), transition: reveal)
}
}