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iOS Build a Game with Sprite Kit Artificial Intelligence and Sound Spawning Enemies

Chris Tapia
Chris Tapia
1,684 Points
Posted by Chris Tapia
Chris Tapia
1,684 Points

Multiple hits

Hey i finished this video and got the same exact results except for one issue. Some enemies would take multiple hits to kill, as opposed to Amit's results where the enemies have the standard one hit kill thing. It is randomly generated, so some enemiees take one hit while others might take 7. What do I do? Please help!!

2 Answers

Nick Janes
Nick Janes
5,487 Points

Hello, I am also having this problem. I don't think its that they take more hits though, I think its just that the hits aren't being registered.

Nick Janes
Nick Janes
5,487 Points

I've done it! I've found the solution. In the didBeginContact method, change this section of code(The first if statement checking collision):

if ( contact.bodyA.categoryBitMask == CollisionCategoryEnemy && contact.bodyB.categoryBitMask == CollisionCategoryProjectile) {

to this(Changing the contact.bodyA and contact.bodyB to firstBody and secondBody): 

if ( firstBody.categoryBitMask == CollisionCategoryEnemy && secondBody.categoryBitMask == CollisionCategoryProjectile) {

My hypothesis to why is because the didBeginContact is constantly being called upon collision because of the other nodes colliding, and due to threading, is changing around the first and second body variables before it can evaluate them.