Question

我想用Swift

在SpriteKit中使用随机位置和方向来制作球

我的代码在objective-c中有效但我正在尝试将其修改为在swift中工作

我使用此代码进行随机性

func randomInRange(low: CGFloat, high: CGFloat) -> CGFloat {
let value = CGFloat(arc4random_uniform(UINT32_MAX)) / CGFloat(UINT32_MAX)
return value * (high - low) + low
}

用于下降方法

//  some constants for the angle and speed values that i am going to use when setting a ball's velocity:

var kCCHaloLowAngle : CGFloat  = (200.0 * 3.14) / 180.0;
    var kCCHaloHighAngle : CGFloat  = (340.0 * 3.14) / 180.0;
    var kCCHaloSpeed: CGFloat = 100.0;

func spawnHaloo ()->()
    {
        // Create ball node.
        let ball : SKSpriteNode = SKSpriteNode(imageNamed:"ball")
        halo.position = CGPointMake(randomInRange(ball.size.width * 0.5, high: self.size.width - (ball.size.width * 0.5)),
            self.size.height + (ball.size.height * 0.5));
        ball.physicsBody = SKPhysicsBody(circleOfRadius:ball.frame.size.width/2)
        let direction : CGVector  = radiansToVector(randomInRange(kCCHaloLowAngle, high: kCCHaloHighAngle));
        ball.physicsBody?.velocity = CGVectorMake(direction.dx * kCCHaloSpeed, direction.dy * kCCHaloSpeed);
        ball.physicsBody?.restitution = 1.0;
        ball.physicsBody?.linearDamping = 0.0;
        ball.physicsBody?.friction = 0.0;
    }


 override func didMoveToView(view: SKView) {


    let action1 = (SKAction.waitForDuration(2.0, withRange: 1.0))
    let action2 = SKAction.runBlock(spawnHaloo)
    let spawnHalo : SKAction = SKAction.sequence([action1,action2])

    let action3 = SKAction.repeatActionForever(spawnHalo)
    self.runAction(action3)

}

在swift中，objective-c代码与此代码之间的差异是这一行

[SKAction performSelector:@selector(spawnHalo) onTarget:self]

而不是我使用

let action2 = SKAction.runBlock(spawnHaloo)

因为当我在swift中使用它时它会给我这个错误

Cannot invoke 'performSelector' with an argument list of type '(selector: (), onTarget: AnyObject.Protocol)'

也许这里有人可以提供帮助吗？

如何在SpriteKit（Swift）中使随机球从上面掉下来？

0 个答案: