我仍然是Swift的初学者，我在SpriteKit中遇到了一些碰撞检测问题。我使用了来自StackOverFlow的this问题，这非常适合展示我如何巧妙地构建事物。但是我的didBegin函数出现了问题，甚至根本没有被调用。我希望我能错过一些简单的东西，你们可以为我看看。
提前致谢。
这里是我的PhysicsCatagoies结构：
import Foundation
import SpriteKit
struct PhysicsCatagories: OptionSet {
let rawValue: UInt32
init(rawValue: UInt32) { self.rawValue = rawValue }
static let None = PhysicsCatagories(rawValue: 0b00000) // Binary for 0
static let Player = PhysicsCatagories(rawValue: 0b00001) // Binary for 1
static let EnemyBullet = PhysicsCatagories(rawValue: 0b00010) // Binary for 2
static let PlayerBullet = PhysicsCatagories(rawValue: 0b00100) // Binary for 4
static let Enemy = PhysicsCatagories(rawValue: 0b01000) // Binary for 8
static let Boss = PhysicsCatagories(rawValue: 0b10000) // Binary for 16
}
extension SKPhysicsBody {
var category: PhysicsCatagories {
get {
return PhysicsCatagories(rawValue: self.categoryBitMask)
}
set(newValue) {
self.categoryBitMask = newValue.rawValue
}
}
}
这里是我在 GameScene 中分配节点的方式：
player.physicsBody = SKPhysicsBody(rectangleOf: player.size)
player.physicsBody!.affectedByGravity = false
player.physicsBody!.categoryBitMask = PhysicsCatagories.Player.rawValue
player.physicsBody!.collisionBitMask = PhysicsCatagories.None.rawValue
player.physicsBody!.category = [.Enemy, .EnemyBullet, .Boss]
bullet.physicsBody = SKPhysicsBody(rectangleOf: bullet.size)
bullet.physicsBody!.affectedByGravity = false
bullet.physicsBody!.categoryBitMask = PhysicsCatagories.PlayerBullet.rawValue
bullet.physicsBody!.collisionBitMask = PhysicsCatagories.None.rawValue
bullet.physicsBody!.category = [.Enemy, .Boss]
enemy.physicsBody = SKPhysicsBody(rectangleOf: enemy.size)
enemy.physicsBody!.affectedByGravity = false
enemy.physicsBody!.categoryBitMask = PhysicsCatagories.Enemy.rawValue
enemy.physicsBody!.collisionBitMask = PhysicsCatagories.None.rawValue
enemy.physicsBody!.category = [.Player, .PlayerBullet]
enemyBullet.physicsBody = SKPhysicsBody(rectangleOf: enemyBullet.size)
enemyBullet.physicsBody!.affectedByGravity = false
enemyBullet.physicsBody!.categoryBitMask = PhysicsCatagories.EnemyBullet.rawValue
enemyBullet.physicsBody!.collisionBitMask = PhysicsCatagories.None.rawValue
enemyBullet.physicsBody!.category = [.Player]
boss.physicsBody = SKPhysicsBody(rectangleOf: boss.size)
boss.physicsBody!.affectedByGravity = false
boss.physicsBody!.categoryBitMask = PhysicsCatagories.Boss.rawValue
boss.physicsBody!.collisionBitMask = PhysicsCatagories.None.rawValue
boss.physicsBody!.category = [.Player, .PlayerBullet]
bulletSpecial.physicsBody = SKPhysicsBody(rectangleOf: bulletSpecial.size)
bulletSpecial.physicsBody!.affectedByGravity = false
bulletSpecial.physicsBody!.categoryBitMask = PhysicsCatagories.PlayerBullet.rawValue
bulletSpecial.physicsBody!.collisionBitMask = PhysicsCatagories.None.rawValue
bulletSpecial.physicsBody!.category = [.Enemy, .Boss]
最后，这是我的didBegin函数，它似乎根本不起作用：
func didBegin(_ contact: SKPhysicsContact) {
let contactCategory: PhysicsCatagories = [contact.bodyA.category, contact.bodyB.category]
switch contactCategory {
case [.Player, .Enemy]:
print("player has hit enemy")
case [.PlayerBullet, .Enemy]:
print("player bullet has hit enemy")
case [.PlayerBullet, .Boss]:
print("player bullet has hit boss")
case [.Player, .Boss]:
print("player has hit boss")
case [.Player, .EnemyBullet]:
print("player has hit enemy bullet")
default:
preconditionFailure("Unexpected collision type: \(contactCategory)")
}
}
答案 0 :(得分：1)
我没有将OptionSet技术用于cagegoryBitMasks，所以我就是这样做的：
定义唯一类别，确保您的课程为SKPhysicsContactDelegate，并让自己成为物理联系代表：
//Physics categories
let PlayerCategory: UInt32 = 1 << 0 // b'00001'
let EnemyBulletCategory: UInt32 = 1 << 1 // b'00010'
let PlayerBulletCategory: UInt32 = 1 << 2 // b'00100'
let EnemyCategory: UInt32 = 1 << 3 // b'01000'
let BossCategory: UInt32 = 1 << 4 // b'10000'
class GameScene: SKScene, SKPhysicsContactDelegate {
physicsWorld.contactDelegate = self
分配类别（通常在didMove(to view:)：
player.physicsBody.catgeoryBitMask = PlayerCategory
bullet.physicsBody.catgeoryBitMask = BulletCategory
enemy.physicsBody.catgeoryBitMask = EnemyCategory
enemyBullet.physicsBody.catgeoryBitMask = EnemyBulletCategory
boss.physicsBody.catgeoryBitMask = BossCategory
（不确定bulletSpecial - 看起来和子弹一样）
设置接触检测：
player.physicsBody?.contactTestBitMask = EnemyCategory | EnemyBulletCategory | BossCategory
bullet.physicsBody?.contactTestBitMask = EnemyCategory | BossCategory
enemy.physicsBody?.contactTestBitMask = PlayerCategory | PlayerBulletCategory
enemyBullet.physicsBody?.contactTestBitMask = PlayerCategory
boss.physicsBody?.contactTestBitMask = PlayerCategory | PlayerBulletCategory
关闭碰撞:(默认情况下已启用）
player.physicsBody?.collisionBitMask = 0
bullet.physicsBody?.collisionBitMask = 0
enemy.physicsBody?.collisionBitMask = 0
enemyBullet.physicsBody?.collisionBitMask = 0
boss.physicsBody?.collisionBitMask = 0
实施didBegin：
func didBegin(_ contact: SKPhysicsContact) {
print("didBeginContact entered for \(String(describing: contact.bodyA.node!.name)) and \(String(describing: contact.bodyB.node!.name))")
let contactMask = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask
switch contactMask {
case PlayerCategory | EnemyCategory:
print("player has hit enemy")
case PlayerBulletCategory | EnemyCategory:
print("player bullet has hit enemy")
case PlayerBulletCategory | BossCategory:
print("player bullet has hit boss")
case PlayerCategory | BossCategory:
print("player has hit boss")
case PlayerCategory | EnemyBulletCategory:
print("player has hit enemy bullet")
default:
print("Undetected collision occurred")
}
}
这里有点晚了，所以希望我没有犯过任何愚蠢的错误。
=======================
您还可以包含此功能，然后在设置完所有物理实体和碰撞并联系位掩码后通过checkPhysics()调用它。它将遍历每个节点并打印出与什么和什么联系人碰撞的内容（它不会检查isDynamic属性，因此请注意）：
//MARK: - Analyse the collision/contact set up.
func checkPhysics() {
// Create an array of all the nodes with physicsBodies
var physicsNodes = [SKNode]()
//Get all physics bodies
enumerateChildNodes(withName: "//.") { node, _ in
if let _ = node.physicsBody {
physicsNodes.append(node)
} else {
print("\(String(describing: node.name)) does not have a physics body so cannot collide or be involved in contacts.")
}
}
//For each node, check it's category against every other node's collion and contctTest bit mask
for node in physicsNodes {
let category = node.physicsBody!.categoryBitMask
// Identify the node by its category if the name is blank
let name = node.name != nil ? node.name : "Category \(category)"
if category == UInt32.max {print("Category for \(String(describing: name)) does not appear to be set correctly as \(category)")}
let collisionMask = node.physicsBody!.collisionBitMask
let contactMask = node.physicsBody!.contactTestBitMask
// If all bits of the collisonmask set, just say it collides with everything.
if collisionMask == UInt32.max {
print("\(name) collides with everything")
}
for otherNode in physicsNodes {
if (node != otherNode) && (node.physicsBody?.isDynamic == true) {
let otherCategory = otherNode.physicsBody!.categoryBitMask
// Identify the node by its category if the name is blank
let otherName = otherNode.name != nil ? otherNode.name : "Category \(otherCategory)"
// If the collisonmask and category match, they will collide
if ((collisionMask & otherCategory) != 0) && (collisionMask != UInt32.max) {
print("\(name) collides with \(String(describing: otherName))")
}
// If the contactMAsk and category match, they will contact
if (contactMask & otherCategory) != 0 {print("\(name) notifies when contacting \(String(describing: otherName))")}
}
}
}
}
它将产生如下输出：
Optional("shape_blueSquare") collides with Optional("Screen_edge")
Optional("shape_redCircle") collides with Optional("Screen_edge")
Optional("shape_redCircle") collides with Optional("shape_blueSquare")
Optional("shape_redCircle") notifies when contacting Optional("shape_purpleSquare")
Optional("shape_redCircle") collides with Optional("shape_greenRect")
Optional("shape_redCircle") notifies when contacting Optional("shape_greenRect")
Optional("shape_purpleSquare") collides with Optional("Screen_edge")
Optional("shape_purpleSquare") collides with Optional("shape_greenRect")
Category for Optional("shape_greenRect") does not appear to be set correctly as 4294967295
Optional("shape_greenRect") collides with Optional("Screen_edge")
Optional("shape_yellowTriangle") notifies when contacting Optional("shape_redCircle")
Optional("shape_yellowTriangle") collides with Optional("shape_greenRect")
Optional("shape_yellowTriangle") notifies when contacting Optional("shape_greenRect")
etc.