Viac telies fyziky v SpriteKit - sprite-kit, skphysicsbody

Mám 40x40 uzol obdĺžnika a chcem zistiť, kedy sa dno dotkne platformy.

Snažil som sa to

let feet = SKPhysicsBody(rectangleOfSize: CGSize(width: hero.frame.size.width, height: 1), center: CGPoint(x: 0, y: -(hero.frame.size.height/2 - 0.5)))

potom nastavte categoryBitMask, collisionBitMask, contactTestBitMaska pridal to hrdinu

hero.physicsBody = SKPhysicsBody(bodies: [feet])

Ale v didBeginContact na println() Copak "t tlače.

Potrebu telo na spodnej časti obdĺžnika a ten na vrchole, pretože ak hrdina udrie platformu zospodu kolízie by ho tlačiť.

aktualizovať

Tu je, ako nastaviť bit masky

let heroFeetCategory: UInt32 = 1 << 0
let edgeCategory: UInt32 = 1 << 1
let groundCategory: UInt32 = 1 << 2

let feet = SKPhysicsBody(rectangleOfSize: CGSize(width: hero.frame.size.width, height: 10), center: CGPoint(x: 0, y: -(hero.frame.size.height/2 - 5)))
feet.collisionBitMask = edgeCategory | groundCategory
feet.contactTestBitMask = groundCategory

feet.categoryBitMask = heroFeetCategory


hero.physicsBody = SKPhysicsBody(bodies: [feet])
hero.physicsBody?.usesPreciseCollisionDetection = true
hero.physicsBody?.velocity = CGVectorMake(0, 0)

hero.physicsBody?.restitution = 0.0
hero.physicsBody?.friction = 0.0
hero.physicsBody?.angularDamping = 0.0
hero.physicsBody?.linearDamping = 1.0

hero.physicsBody?.allowsRotation = false
hero.physicsBody?.mass = 0.0641777738928795

world.addChild(hero)

a na zem

let ground = SKSpriteNode(color: UIColor.whiteColor(), size: CGSizeMake(38, 38))
ground.name = "groundName"
ground.position = CGPoint(x: 0, y: -(self.frame.size.height/2 - ground.frame.size.height/2))

ground.physicsBody = SKPhysicsBody(rectangleOfSize: ground.size)
ground.physicsBody?.collisionBitMask = edgeCategory | heroFeetCategory
ground.physicsBody?.contactTestBitMask = heroFeetCategory
ground.physicsBody?.categoryBitMask = groundCategory
world.addChild(ground)

A ako môžem zistiť, ak sa dotknú

func didBeginContact(contact: SKPhysicsContact) {

var notTheHero: SKPhysicsBody!;

if (contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask) {
notTheHero = contact.bodyB;
} else {
notTheHero = contact.bodyA;
}

println(notTheHero.node) // print "heroName"
if (notTheHero.categoryBitMask == groundCategory) {
println("touch began?"); // is never called
}
}

odpovede:

kolízie je fajn, ale pri tlači s Názov uzla"cez telo fyziky notTheHero.node len prístup SKNode, a nie NSString objekt z jeho meno. Namiesto toho skúste niečo ako println(notTheHero.node.name);