我在Swift中编写了这个简单的太空游戏,直到遇到碰撞检测问题为止。在浏览论坛,教程等之后,我尝试通过声明位掩码来实现冲突,如下所示:
对象1
enemy?.physicsBody = SKPhysicsBody(circleOfRadius: ((enemy?.size.width)!/2)) enemy?.physicsBody?.categoryBitMask = enemyBitMask enemy?.physicsBody?.contactTestBitMask = bulletBitMask enemy?.physicsBody?.collisionBitMask = 0
对象2
bullet?.physicsBody? = SKPhysicsBody(rectangleOf: (bullet?.size)!) bullet?.physicsBody?.categoryBitMask = bulletBitMask bullet?.physicsBody?.contactTestBitMask = enemyBitMask bullet?.physicsBody?.collisionBitMask = 0 bullet?.physicsBody?.usesPreciseCollisionDetection = true
我也将打印声明放在
func didBegin(_ contact: SKPhysicsContact) { print("Hello") }
这是我配置精灵的方法:
func CreateNewEnemy() { var enemy : SKSpriteNode? let moveEnemyDown = SKAction.repeatForever(SKAction.moveBy(x: 0, y: -1, duration: 0.01)) let rotateEnemy = SKAction.repeatForever(SKAction.rotate(byAngle: 25, duration: 5)) let enemyXpos = randomNum(high: self.frame.size.width/2, low: -1 * self.frame.size.width/2) let enemyYpos = randomNum(high: 2.5*self.frame.size.height, low: self.frame.size.height/2) let enemyOrigin : CGPoint = CGPoint(x: enemyXpos, y: enemyYpos) enemy = SKSpriteNode(imageNamed: possibleEnemyImage[Int(arc4random_uniform(4))]) print(enemy?.size.height) enemy?.scale(to: CGSize(width: player.size.height, height: player.size.height)) print(enemy?.size.height) enemy?.position = enemyOrigin enemy?.run(moveEnemyDown) enemy?.run(rotateEnemy) let enemyRadius : CGFloat = (enemy?.size.width)!/2 print(enemyRadius) enemy?.physicsBody? = SKPhysicsBody(circleOfRadius: enemyRadius) enemy?.physicsBody?.categoryBitMask = enemyCategory enemy?.physicsBody?.contactTestBitMask = bulletCategory enemy?.physicsBody?.collisionBitMask = 0 enemy?.zPosition = 1 enemiesArray.append(enemy!) self.addChild(enemy!) }
创造敌人(被召唤进入查看功能)
func CreateAllEnemies(amountOfEnemies : UInt8) { for _ in 0...amountOfEnemies { CreateNewEnemy() } }
和另一个精灵
func CreateNewBullet() { let bulletOrigin : CGPoint = CGPoint(x: player.position.x, y: player.position.y+player.size.height/2) let moveBulletUp = SKAction.repeatForever(SKAction.moveBy(x: 0, y: 3, duration: 0.01)) var bullet : SKSpriteNode? bullet = SKSpriteNode(imageNamed: "bulletImage") bullet?.position = bulletOrigin bullet?.run(moveBulletUp) bullet?.physicsBody? = SKPhysicsBody(rectangleOf: (bullet?.size)!) bullet?.physicsBody?.categoryBitMask = bulletCategory bullet?.physicsBody?.contactTestBitMask = enemyCategory bullet?.physicsBody?.collisionBitMask = 0 bullet?.physicsBody?.isDynamic = true bullet?.physicsBody?.usesPreciseCollisionDetection = true bullet?.zPosition = 1 bulletsArray.append(bullet!) self.addChild(bullet!) }
这个是用计时器创建的
bulletTimer = Timer.scheduledTimer(timeInterval: 0.25, target: self, selector: #selector(CreateNewBullet) , userInfo: nil, repeats: true)
不幸的是,当我看到两个对象接触后,它无法在控制台中打印任何内容。
SKPhysicsContactDelegate
//Physics categories
let enemyCategory: UInt32 = 1 << 1 let bulletCategory: UInt32 = 1 << 2 class GameScene: SKScene, SKPhysicsContactDelegate { physicsWorld.contactDelegate = self
didMove(to view:)
enemy.physicsBody.catgeoryBitMask = enemyCategory bullet.physicsBody.catgeoryBitMask = bulletCategory
(确保已为每个节点创建了物理实体)
enemy.physicsBody?.collisionBitMask = 0 // enemy collides with nothing bullet.physicsBody?.collisionBitMask = 0 // bullet collides with nothing
enemy.physicsBody?.collisionBitMask = 0 // enemy collides with nothing
bullet.physicsBody?.collisionBitMask = 0 // bullet collides with nothing
甚至:
for node in [enemy, bullet] { node.physicsBody?.collisionBitMask = 0 // collides with nothing }
bullet.physicsBody?.collisionBitMask = enemyCategory // bullet contacts enemy
确保每个潜在接触中涉及的至少一个对象isDynamic的物理实体上的属性设置为true,否则将不会生成任何接触。两个对象都不必是动态的。
isDynamic
true
didBegin当子弹和敌人接触时,您现在应该被呼叫。您可以这样编写didBegin:
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 bulletCategory | enemyCategory: print("bullet and enemy have contacted.") let bulletNode = contact.bodyA.categoryBitMask == bulletCategory ? contact.bodyA.node : contact.bodyB.node enemyHealth -= 10 bulletNode.removeFromParent default: print("Some other contact occurred") }
}