快速图像堆叠/复制-iOS

Question

i've recently started coding and my first attempt is an iOS game, part of the game I'm working on has the following elements.

Scrolling foreground and background A cat that jumps when clicked A missile raining down from above.

I've recently managed to spawn the missile every few seconds however in doing so I think i've messed up something.

Now i have two errors, the first is the cat, foreground and background images duplicating and stacking themselves all over the screen and the other is a build error under override func update(currentTime . I've commented out the cat's Z rotation as otherwise the game wont build.

If anyone can help me work out how to fix I'd be really grateful.

Sorry if it's overkill, but here is the code....

import SpriteKit

class GameScene: SKScene, SKPhysicsContactDelegate {


var cat = SKSpriteNode()
var crow = SKSpriteNode()
var crowTexture1 = SKTexture()
var skyColor = SKColor()
var moveAndRemoveCrow = SKAction()
var spawn = SKAction()
var lastMissileAdded : NSTimeInterval = 0.0

let missileVelocity : CGFloat = 5.0



override func didMoveToView(view: SKView) {

    self.addMissile()

}


func addMissile() {
    // Initializing missile node
    var missile = SKSpriteNode(imageNamed: "red-missile")
    missile.setScale(0.15)

    // Adding SpriteKit physics body for collision detection
    missile.physicsBody = SKPhysicsBody(rectangleOfSize: missile.size)
    //      missile.physicsBody?.categoryBitMask = UInt32(obstacleCategory)
    missile.physicsBody?.dynamic = true
    //      missile.physicsBody?.contactTestBitMask = UInt32(shipCategory)
    missile.physicsBody?.collisionBitMask = 0
    missile.physicsBody?.usesPreciseCollisionDetection = true
    missile.name = "missile"

    // Selecting random y position for missile
    var random : CGFloat = CGFloat(arc4random_uniform(300))
    missile.position = CGPoint(x: self.frame.size.width / 1.8, y: self.frame.size.height / 1.2 )
    self.addChild(missile)
}

func moveObstacle() {
    self.enumerateChildNodesWithName("missile", usingBlock: { (node, stop) -> Void in
        if let obstacle = node as? SKSpriteNode {
            obstacle.position = CGPoint(x: obstacle.position.x - self.missileVelocity, y: obstacle.position.y)
            if obstacle.position.x < 0 {
                obstacle.removeFromParent()
            }
        }
    })


    skyColor = SKColor(red:113.0/255.0, green:197.0/255.0, blue:207.0/255.0, alpha:1.0)
    self.backgroundColor = skyColor

    var catTexture1 = SKTexture(imageNamed: "Cat1")
    catTexture1.filteringMode = SKTextureFilteringMode.Nearest
    var catTexture2 = SKTexture(imageNamed: "Cat2")
    catTexture2.filteringMode = SKTextureFilteringMode.Nearest

    var anim = SKAction.animateWithTextures([catTexture1, catTexture2], timePerFrame: 0.2)
    var run = SKAction.repeatActionForever(anim)

    cat = SKSpriteNode(texture: catTexture1)
    cat.position = CGPoint(x: self.frame.size.width / 2.2, y: self.frame.size.height / 7.0 )
    cat.runAction(run)

    cat.physicsBody = SKPhysicsBody(circleOfRadius: cat.size.height / 2.0)
    cat.physicsBody!.dynamic = true
    cat.physicsBody!.allowsRotation = false

    self.addChild(cat)


    var groundTexture = SKTexture(imageNamed: "Ground")
    groundTexture.filteringMode = SKTextureFilteringMode.Nearest

    var moveGroundSprite = SKAction.moveByX(-groundTexture.size().width, y: 0, duration: NSTimeInterval(0.01 * groundTexture.size().width))
    var resetGroundSprite = SKAction.moveByX(groundTexture.size().width, y: 0, duration: 0.0)
    var moveGroundSpritesForever = SKAction.repeatActionForever(SKAction.sequence([moveGroundSprite,resetGroundSprite]))

    for var i:CGFloat = 0; i < 2 + self.frame.size.width / ( groundTexture.size().width); ++i {
        var sprite = SKSpriteNode(texture: groundTexture)
        sprite.position = CGPointMake(i * sprite.size.width, sprite.size.height / 2)
        sprite.runAction(moveGroundSpritesForever)
        self.addChild(sprite)

    }

    var dummy = SKNode()
    dummy.position = CGPointMake(0, groundTexture.size().height / 2)
    dummy.physicsBody = SKPhysicsBody(rectangleOfSize: CGSizeMake(self.frame.size.width, groundTexture.size().height))
    dummy.physicsBody!.dynamic = false
    self.addChild(dummy)

    var skylineTexture = SKTexture(imageNamed: "Skyline")
    skylineTexture.filteringMode = SKTextureFilteringMode.Nearest

    var moveSkylineSprite = SKAction.moveByX(-skylineTexture.size().width, y: 0, duration: NSTimeInterval(0.1 * skylineTexture.size().width))
    var resetSkylineSprite = SKAction.moveByX(skylineTexture.size().width, y: 0, duration: 0.0)
    var moveSkylineSpritesForever = SKAction.repeatActionForever(SKAction.sequence([moveSkylineSprite,resetSkylineSprite]))

    for var i:CGFloat = 0; i < 2 + self.frame.size.width / ( skylineTexture.size().width); ++i {
        var sprite = SKSpriteNode(texture: skylineTexture)
        sprite.zPosition = -20;
        sprite.position = CGPointMake(i * sprite.size.width, sprite.size.height / 2 + groundTexture.size().height)
        sprite.runAction(moveSkylineSpritesForever)
        self.addChild(sprite)
    }

}

override func  touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
    /* Called when a touch begins */

    cat.physicsBody!.velocity = CGVectorMake(0, 0)
    cat.physicsBody!.applyImpulse(CGVectorMake(0, 15))

}

func clamp(min: CGFloat, max: CGFloat, value: CGFloat) -> CGFloat {
    if( value > max ) {
        return max;
    } else if( value < min ) {
        return min;
    } else {
        return value;
    }

}
override func update(currentTime: CFTimeInterval) {
    /* Called before each frame is rendered */
    //       cat.zRotation = self.clamp( -1, max: 0.5, value: cat.physicsBody!.velocity.dy * ( cat.physicsBody!.velocity.dy < 0 ? 0.003 : 0.001 ) );
    if currentTime - self.lastMissileAdded > 1 {
        self.lastMissileAdded = currentTime + 1
        self.addMissile()
    }

    self.moveObstacle()
}


}

Answer 1

I've figured it out,

I had functions in 'didMoveToView'. After moving them outside the block the code now runs smoothly.