SKView,SKScene,SKSpriteNode和SKAction的認識

Sprite Kit內容被放置在一個窗口中，就像其他可視化內容那樣。Sprite Kit內容由SKView類渲染呈現。SKView對象渲染的內容稱爲一個場景，它是一個SKScene對象。場景參與響應鏈，還有其他使它們適合於遊戲的功能。
SKSpriteNode(用於繪製精靈紋理);
SKAction用於創建節點動作。
相關的一些代碼：
- (void)viewDidLoad
{
    [super viewDidLoad];


    // Configure the view.
    SKView * skView = (SKView *)self.view;
    skView.showsFPS = YES;
    skView.showsNodeCount = YES;
    
    // Create and configure the scene.
    SKScene * scene = [MSMyScene sceneWithSize:skView.bounds.size];
    scene.scaleMode = SKSceneScaleModeAspectFill;
    
    // Present the scene.
    [skView presentScene:scene];
}


-(id)initWithSize:(CGSize)size {    
    if (self = [super initWithSize:size]) {
        /* Setup your scene here */
        
        self.backgroundColor = [SKColor colorWithRed:0.15 green:0.15 blue:0.3 alpha:1.0];
        
        SKLabelNode *myLabel = [SKLabelNode labelNodeWithFontNamed:@"Chalkduster"];
        
        myLabel.text = @"Hello, World!";
        myLabel.fontSize = 30;
        myLabel.position = CGPointMake(CGRectGetMidX(self.frame),
                                       CGRectGetMidY(self.frame));
        
        [self addChild:myLabel];
    }
    return self;
}


-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    /* Called when a touch begins */
    
    for (UITouch *touch in touches) {
        CGPoint location = [touch locationInNode:self];
        
        SKSpriteNode *sprite = [SKSpriteNode spriteNodeWithImageNamed:@"Spaceship"];
        
        sprite.position = location;
        
        SKAction *action = [SKAction rotateByAngle:M_PI duration:5];
        
        [sprite runAction:[SKAction repeatActionForever:action]];
        
        [self addChild:sprite];
    }
}