相加的4幅图片的背景

Question

请帮帮忙。

我有四张照片。我想用动画展示背景。

每一张图片都应该落在之前的动画alpha上。因此，我得到了一个背景的4个图片为对方添加。

首先显示1.ng淡出阿尔法到1，直到一个人还没有出现，直到结束，启动第二个图像，等等。

     var waitTime:NSTimeInterval    = 0
     var durTime:NSTimeInterval     = 4.4

     for var i = 0; i < 4; i++ {

            let frostImage = SKSpriteNode(imageNamed: "a\(i)")
            frostImage.position = CGPointMake(0, 0)
            frostImage.zPosition = -1
            frostImage.alpha = 0
            frostImage.anchorPoint = CGPointZero
            frostImage.size  = CGSizeMake(256, 384)
            self.addChild(frostImage)

            self.array.addObject(frostImage)

            let w = SKAction.waitForDuration(waitTime)
            let s = SKAction.fadeAlphaTo(0.6, duration: durTime)
            let a = SKAction.repeatAction(SKAction.sequence([w, s]), count: 1)


            durTime -= 0.4
            waitTime += 0.2

            self.arrayAnim.addObject(a)
        }


then 



            for node in self.array {
                node.runAction(self.arrayAnim[ind1] as SKAction, completion: nil)
                ind1++
            }

Answer 1

我给你写了信，但在目标-c中，我想你可以把它转换成斯威夫特。

    SKSpriteNode *bg1 = [SKSpriteNode spriteNodeWithImageNamed:@"bg1"];
    bg1.zPosition = 1;
    SKSpriteNode *bg2 = [SKSpriteNode spriteNodeWithImageNamed:@"bg2"];
    bg2.zPosition = 2;
    SKSpriteNode *bg3 = [SKSpriteNode spriteNodeWithImageNamed:@"bg3"];
    bg3.zPosition = 3;
    SKSpriteNode *bg4 = [SKSpriteNode spriteNodeWithImageNamed:@"bg4"];
    bg4.zPosition = 4;

    SKAction *action = [SKAction fadeAlphaTo:1.0 duration:1];
    SKAction *wait = [SKAction waitForDuration:1];
    SKAction *resetAlpha = [SKAction fadeAlphaBy:0.0 duration:0];

    [self runAction:[SKAction repeatActionForever:[SKAction sequence:@[[SKAction runBlock:^{
        [bg1 runAction:resetAlpha];
        [bg2 runAction:resetAlpha];
        [bg3 runAction:resetAlpha];
        [bg4 runAction:resetAlpha];
    }], [SKAction runBlock:^{
        [bg1 runAction:action];
    }], wait, [SKAction runBlock:^{
        [bg2 runAction:action];
    }], wait, [SKAction runBlock:^{
        [bg3 runAction:action];
    }], wait, [SKAction runBlock:^{
        [bg4 runAction:action];
    }], wait]]]];