位掩碼不起作用。 SpriteKit Swift

Question

有一個硬幣，它只能與玩家碰撞而不是推動它。 相反，玩家（手指）被推下並與所有物體碰撞。 這是代碼：

var coin=SKSpriteNode(imageNamed: "Coin")
coin.position=CGPoint(x: xPos, y: yPos)
coin.physicsBody=SKPhysicsBody(circleOfRadius: 250)
//coin.physicsBody!.mass=CGFloat(mass);
coin.xScale=1
coin.yScale=1

coin.name="coin";
coin.physicsBody?.contactTestBitMask=1
coin.physicsBody!.collisionBitMask=0
coin.physicsBody!.categoryBitMask=0

self.addChild(coin)

這是播放器的設置：

Finger.physicsBody?.collisionBitMask=0;
Finger.physicsBody?.categoryBitMask=0;
Finger.physicsBody?.contactTestBitMask=1

Answer 1

問題在於硬幣的碰撞位掩碼設置為玩家的categoryBitMask。 讓我為您揭開這三個碰撞變量的神秘面紗：

x.categoryBitMask：這是一種為對象“ x”提供識別它的方法。

x.collisionBitMask：在這里，您將放置您希望“ x”能夠與之碰撞的對象的categoryBitMask變量（崩潰）

x.contactTestBitMask：在這里，您將放置當對象與“ x”進行接觸時要為其執行操作的對象的categoryBitMask var。 contactTestBitMask將調用蘋果提供的函數“ didBeginContact”，並且您可以在其中編寫當硬幣碰到玩家時想要發生的事情。

一些代碼可以幫助您將各個部分組合在一起：

var coinCategory: UInt32 = 1 // categories must be type UInt32
var playerCategory: UInt32 = 2
var nothingCategory: UInt32 = 3 // some other number for not colliding into anything

coin.name="coin";
coin.physicsBody!.categoryBitMask= coinCategory // set category first
coin.physicsBody?.contactTestBitMask = playerContact
coin.physicsBody!.collisionBitMask = nothingCategory // doesn't crash into anything. 
// if you want coins to crash into each other then set their collisionBitMask to the coinCategory  


self.addChild(coin)

和：

Finger.physicsBody?.categoryBitMask= playerCategory;
Finger.physicsBody?.collisionBitMask= nothingCategory;

// This next one only needs to be set on one of the objects when you want the "didBeginContact" function to be called when there is contact
//Finger.physicsBody?.contactTestBitMask = coinCategory

祝好運！

Answer 2

最佳實踐是不對位掩碼使用整數值：

var coinCategory: UInt32 = 0x1 << 1 
var playerCategory: UInt32 = 0x1 << 2
var nothingCategory: UInt32 = 0x1 << 3