ios - 如何在 Sprite Kit 中初始化所有场景？

Question

每当我想要转换到某个场景时，SKTransition 甚至需要几秒钟才能开始。是否可以在游戏开始前初始化所有场景？

NewScene *newScene = [NewScene sceneWithSize:self.size];
SKTransition *reveal = [SKTransition moveInWithDirection:SKTransitionDirectionUp duration:0.5];
reveal.pausesIncomingScene = NO;
[self.view presentScene:newScene transition:reveal];

我也用 didMoveToView 尝试过:

@implementation NewScene
-(id)initWithSize:(CGSize)size {
    if(self = [super initWithSize:size]) {
    // Load a bunch of stuff like this:
    SKSpriteNode *menuButton = [SKSpriteNode spriteNodeWithImageNamed:@"mainMenu"];
    menuButton.position = CGPointMake(self.frame.size.width/2,self.frame.size.height/4);
    menuButton.name = @"menuButton";
    [self addChild:menuButton];
    [menuButton setScale:0.8];
    }
}

如何确保我的 Sprite Kit 游戏顺利运行？

编辑: 事实证明，问题是我一直让主线程进入休眠状态以淡出音乐。我已经让所有音频方法在后台运行，现在工作正常。

Answer 1

一个好的方法是在 SKScene 初始化之前异步加载所有资源。苹果在 Adventure game 中使用了这种方法:

NewScene.h:

typedef void (^AGAssetLoadCompletionHandler)(void);

@interface GameScene : SKScene<SKPhysicsContactDelegate, UIGestureRecognizerDelegate>

+ (void)loadSceneAssetsWithCompletionHandler:(AGAssetLoadCompletionHandler)handler;

@end

NewScene.m:

@implementation NewScene

-(id)initWithSize:(CGSize)size {
    if(self = [super initWithSize:size]) {
    // Load a bunch of stuff like this:
    SKSpriteNode *menuButton = [SKSpriteNode spriteNodeWithTexture:[self menuButtonTexture];
    menuButton.position = CGPointMake(self.frame.size.width/2,self.frame.size.height/4);
    menuButton.name = @"menuButton";
    [self addChild:menuButton];
    [menuButton setScale:0.8];
    }
}

#pragma mark - Shared Assets

+ (void)loadSceneAssetsWithCompletionHandler:(AGAssetLoadCompletionHandler)handler {
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
        // Load the shared assets in the background.
        [self loadSceneAssets];

        if (!handler) {
            return;
        }

        dispatch_async(dispatch_get_main_queue(), ^{
            // Call the completion handler back on the main queue.
            handler();
        });
    });
}

+ (void)loadSceneAssets {
    sBackgroundTexture = [SKTexture textureWithImageNamed:@"background"];
    sMenuButtonTexture = [SKTexture textureWithImageNamed:@"mainMenu"];
    // etc.
}

static SKTexture *sBackgroundTexture = nil;
- (SKTexture *)backgroundTexture {
    return sBackgroundTexture;
}

static SKTexture *sMenuButtonTexture = nil;
- (SKTexture *)menuButtonTexture {
    return sMenuButtonTexture;
}

@end

然后只需从您的 UIViewController 中呈现 NewScene:

if (!self.skView.scene) {
    CGSize viewSize = self.view.bounds.size;
    // Here you can present some loading scene or splash screen

    [NewScene loadSceneAssetsWithCompletionHandler:^{
        NewScene *scene = [[NewScene alloc] initWithSize:viewSize];
        [self.skView presentScene:scene transition:[SKTransition crossFadeWithDuration:1.f]];
    }];
}