Prevent SKSpriteNode from bouncing off other SKSpriteNode - sprite-kit

Question

I have a SKSpriteNode that collides and bounces off another SKSpriteNode. What I want is to be able to detect the collision, but not have it bounce off. I want it to bounce off other nodes, but not this one. Is that possible?
self.physicsWorld.contactDelegate = self;
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:self.frame];
self.physicsWorld.gravity = CGVectorMake(0.0f, 0.0f);
self.zone = [SKSpriteNode spriteNodeWithImageNamed:#"Oval.png"];
self.zone.position = CGPointMake(CGRectGetMidX(self.frame),CGRectGetMidY(self.frame)); self.zone.xScale = 0.3;
self.zone.yScale = 0.3;
self.zone.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:self.zone.frame.size.width/2];
self.zone.physicsBody.restitution = 0.0f;
self.zone.physicsBody.density = 0;
self.zone.physicsBody.friction = 0.4f;
self.zone.physicsBody.categoryBitMask = zoneCategory;
self.zone.physicsBody.dynamic = NO;
self.ball = [SKSpriteNode spriteNodeWithImageNamed:#"Ball.png"];
self.ball.position = CGPointMake(80,0);
self.ball.name = #"BallNode";//how the node is identified later
self.ball.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:self.ball.frame.size.width/2];
self.ball.physicsBody.restitution = 0.1f;
self.ball.physicsBody.friction = 0.4f;
self.ball.physicsBody.categoryBitMask = ballCategory;
self.ball.physicsBody.dynamic = NO;
I don't want ball and zone to bounce. Any ideas?

Answer 1

set collisionBitMask and contactTestBitMask of those two bodies
like:
self.zone.collisionBitMask = 0xFFFFFFFF & (~ballCategory);
self.ball.collisionBitMask = 0xFFFFFFFF & (~zoneCategory);
self.zone.contactTestBitMask = ballCategory;
then when contact occurs expect call of didBeginContact: in your SKPhysicsContactDelegate.
There will be no collsion.