Detecting collision on SpriteKit from two objects - swift

Question

I am having some trouble detecting the collision of two objects when i shoot from my cannon. The goal is to shoot a bullet from it and remove as soon as it colides with the obstacle. It seems there is no collision going on at all in the game, since i cannot receive the "Collision" message i set. Take a look at the following code:
class GameScene: SKScene, SKPhysicsContactDelegate {
enum BodyType: UInt32 {
case bullet = 1
case line = 2
case breaker = 4
}
i've enumerated the components so i can set them in the category Bitmask. After that, i did a setup from shooting when a touch begins.
override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
/* Called when a touch begins */
for touch in (touches as! Set<UITouch>) {
let bullet = SKSpriteNode(imageNamed: "bullet.png")
bullet.position = self.shooterTriangle.position
var actionRotate = SKAction.rotateToAngle(CGFloat(2 * -M_PI), duration: NSTimeInterval(0.1))
let actionMove = SKAction.moveTo(CGPoint(x: 500, y: size.height * 0.5), duration: NSTimeInterval(0.5))
let removeBullet = SKAction.removeFromParent()
bullet.runAction(SKAction.sequence([actionRotate]))
bullet.runAction(SKAction.sequence([actionMove, removeBullet]))
addChild(bullet)
// Bullet Physics Start ****
bullet.physicsBody? = SKPhysicsBody(circleOfRadius: bullet.size.width/2.0)
bullet.physicsBody?.dynamic = true
bullet.physicsBody?.affectedByGravity = false
bullet.physicsBody?.allowsRotation = false
bullet.physicsBody?.categoryBitMask = BodyType.bullet.rawValue
bullet.physicsBody?.contactTestBitMask = BodyType.line.rawValue
bullet.physicsBody?.collisionBitMask = BodyType.line.rawValue
}
}
Then i`ve add the line i want the bullet to colide with in a loadGameComponents function...
func loadGameComponents() {
//Load line....
let line = SKSpriteNode(imageNamed: "Line_1.png")
line.position = CGPoint(x: size.width * 0.95, y: size.height * (2.0))
addChild(line)
var actualSpeedDuration = 2.2
let lineActionMove = SKAction.moveTo(CGPoint(x: size.width * 0.95, y: size.height * 0.6), duration: NSTimeInterval(actualSpeedDuration))
line.runAction(SKAction.sequence([lineActionMove]))
// Line Physics starts! *****
line.physicsBody? = SKPhysicsBody(rectangleOfSize: CGSize(width: line.size.width, height: line.size.height))
line.physicsBody?.dynamic = false
line.physicsBody?.affectedByGravity = false
line.physicsBody?.allowsRotation = false
line.physicsBody?.categoryBitMask = BodyType.line.rawValue
line.physicsBody?.contactTestBitMask = BodyType.bullet.rawValue
line.physicsBody?.collisionBitMask = 0
Finally, i've defined the contactDelegate = self in my didLoad function and included the didBeginContact method
func didBeginContact(contact: SKPhysicsContact) {
println("Contact!!!")
}
I am not receiving the message at all, but i am not sure what is going wrong!
Thanks for the patience! :)

Answer 1

Looks like the main problem is that i used to place the optional indicator (?) when declaring the physics body of an sprite. correction should be made in this lines...
line.physicsBody? = SKPhysicsBody(rectangleOfSize: CGSize(width: line.size.width, height: line.size.height))
bullet.physicsBody? = SKPhysicsBody(circleOfRadius: bullet.size.width/2.0)
Removing them solved my problem :)
I also included the view.showPhysics = true in my didMoveToView method so it is easy to see the boundaries between the sprites.