Swift - Random collisions are not detected - swift

Question

In my game, I use SKSprite. Some collisions are not detected. I did 10 tries, collisions are working well but about 25% of collisions that are supposed to be detected are not detected. I have NO idea why, I tried many things. Collisions are only with nodes of the same category.
I have no idea why randomly some collisions are not made when I can obviously see them, do you have any idea? Thanks for your help.
Here is the code of didBeginContact:
func didBeginContact(contact: SKPhysicsContact) {
var firstBody: SKPhysicsBody = contact.bodyA
var secondBody: SKPhysicsBody = contact.bodyB
if firstBody.categoryBitMask == secondBody.categoryBitMask {
listContacts.append([firstBody.node!,secondBody.node!])
}
}
}
Here is the code of didEndContact:
func didEndContact(contact: SKPhysicsContact) {
var firstBody: SKPhysicsBody = contact.bodyA
var secondBody: SKPhysicsBody = contact.bodyB
if contact.bodyA.categoryBitMask == contact.bodyB.categoryBitMask {
for i in listContacts{
if (i.contains(firstBody.node!) && i.contains(secondBody.node!)){
let findIndex = listContacts.indexOf { $0 == i }
listContacts.removeFirst(findIndex!)
}
}
}
Finally when I declare a new SKSpriteNode I set this:
rectangle.physicsBody = SKPhysicsBody(rectangleOfSize: rectangle.size)
rectangle.physicsBody?.dynamic = true
rectangle.physicsBody?.collisionBitMask = PhysicsCategory.None
usesPreciseCollisionDetection = true doesn't change anything so I don't use usePrecisionCollisionDetection
Every SKSpriteNode has his categoryBitmask and contactTestBitmask equal because only same SKSpriteNodes are supposed to collide.
Also:
physicsWorld.gravity = CGVectorMake(0, 0)
physicsWorld.contactDelegate = self
Finally here is a short video of my game if you want to understand easily what happens (problem of collisions are between rectangles) https://www.youtube.com/watch?v=-pbmKwQiE9U

Answer 1

You seem to be checking if the categoryBitMask of body A equals body B.
if firstBody.categoryBitMask == secondBody.categoryBitMask {
listContacts.append([firstBody.node!,secondBody.node!])
}
}
This will only run an action if a node hits a node with the same categoryBitMask
You should be checking the collisionBitMasks to see if you have a collision, or you can check the name.
For an example using categoryBitMask you can do something like this:
func didBeginContact(contact: SKPhysicsContact) {
var sprite: SKSpriteNode!
if contact.bodyA.categoryBitMask == <your category bitmask> {
sprite = contact.bodyA.node! as! SKSpriteNode
}
else if contact.bodyB.categoryBitMask == <your category bitmask> {
sprite = contact.bodyB.node! as! SKSpriteNode
}
// Do something with sprite....
// You can also create another sprite, and assign it to the other body, and perform functions on it, or both A and B.
// It is good to have different functions you send can send the nodes to once you find out which ones they are.
}
You can do these checks to see which sprites are hitting each other.

Answer 2

I just fixed it! The reason was that in the function "touchesEnded", I had a recursive function that was deleting bad connections in the listContacts!