预设节点不会与用户创建的节点发生冲突

Question

示例：

这堵墙是在荷载处预设的，

var preWall = SKSpriteNode(texture: preWallTexture, size: CGSize(width: width, height: height))

preWall.position = CGPoint(x: x, y: y)

preWall.physicsBody = SKPhysicsBody(edgeLoopFromRect: CGRect(x: x, y: y, width: width, height: height))
preWall.physicsBody?.affectedByGravity = false
preWall.physicsBody?.dynamic = false
preWall.physicsBody?.categoryBitMask = BLOCK

preWall.name = "preWall"

self.addChild(preWall)

这些 "sand" 粒子是在用户触摸生成器（屏幕上的红色方块）后创建的，

var img = "BlockRed.png"
let sand = SKSpriteNode (imageNamed: img)
var randLoc = arc4random_uniform(26)
sand.position = CGPointMake(location.x - CGFloat(10) + CGFloat(randLoc), location.y)
sand.name = "redSand"
sand.zPosition = 0
self.addChild(sand)

//gravity
sand.physicsBody?.affectedByGravity = true

//contact
sand.physicsBody!.categoryBitMask = PARTICLE
sand.physicsBody?.collisionBitMask = BLOCK | PARTICLE
sand.physicsBody?.contactTestBitMask = BLOCK | PARTICLE
sand.physicsBody = SKPhysicsBody(circleOfRadius: sand.frame.width - 3)

然而，当它们接触时，粒子会穿过墙壁掉落。为什么会发生这种情况，我该如何解决？

注：

// Constants
let NOTHING: UInt32    = 0x1 << 0
let PARTICLE: UInt32   = 0x1 << 1
let BLOCK: UInt32      = 0x1 << 2

Answer 1

设置 bit masks 后，您正在初始化沙粒的 physics body。尝试更改行的顺序。

sand.physicsBody = SKPhysicsBody(circleOfRadius: sand.frame.width - 3)
sand.physicsBody?.categoryBitMask = PARTICLE
sand.physicsBody?.collisionBitMask = BLOCK | PARTICLE
sand.physicsBody?.contactTestBitMask = BLOCK | PARTICLE

Answer 2

预设节点的物理体不是基于体积的体，因此没有与沙粒碰撞。我切换自：

preWall.physicsBody = SKPhysicsBody(edgeLoopFromRect: CGRect(x: x, y: y, width: width, height: height))

至

preWall.physicsBody = SKPhysicsBody(rectangleOfSize: preWall.frame.size)

预设节点不会与用户创建的节点发生冲突

Pre-set nodes not colliding with user-touched created nodes

swift

sprite-kit

skspritenode

skphysicsbody