iOS - SpriteKit : ApplyImpulse not working on SKSpriteNode - ios

Question

I'm kind of new with SpriteKit and I'm having some troubles with the physics, I've tried many things to make a SKSpriteNode move with a force or an impulse but it never moves, only gravity affects it when i set it.
-(id)initWithSize:(CGSize)size {
if (self = [super initWithSize:size]) {
self.anchorPoint = CGPointMake(0.5, 0.5);
myWorld = [SKNode node];
[self addChild:myWorld];
SKSpriteNode* map = [SKSpriteNode spriteNodeWithImageNamed:#"grass"];
[myWorld addChild:map];
self.physicsBody = [SKPhysicsBody bodyWithEdgeLoopFromRect:map.frame];
self.physicsBody.friction = 0.0f;
self.physicsBody.categoryBitMask = 2;
self.physicsWorld.gravity = CGVectorMake(0.0, 0.0);
self.physicsWorld.contactDelegate = self;
pointOfView = [SKSpriteNode spriteNodeWithColor:[UIColor colorWithWhite:1 alpha:0.2] size:CGSizeMake(300, 548)];
[myWorld addChild:pointOfView];
pointOfView.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:pointOfView.frame.size];
pointOfView.physicsBody.friction = 0.0f;
pointOfView.physicsBody.restitution = 1.0f;
pointOfView.physicsBody.linearDamping = 0.0f;
pointOfView.physicsBody.allowsRotation = NO;
pointOfView.physicsBody.collisionBitMask = 2;
pointOfView.physicsBody.categoryBitMask = 3;
[pointOfView.physicsBody applyImpulse:CGVectorMake(10.0f, -10.0f)];
}
return self;
}
Here is most of my code in my main scene, there's nothing else except some empty methods like update or touchesBegan.. Am I missing something ? I've tried so many things, i'm starting to lose it haha
Thanks very much for any help !

Answer 1

It's a bit late, but the answer is here: Not able to apply impulse to SKSpriteNode physics body
The problem is that you've created a physics body with bodyWithEdgeLoopFromRect; this creates a static physics body which won't respond to applyImpulse. You need to add the physics body using bodyWithRectangleOfSize: instead.

Answer 2

pointOfView.physicsBody.dynamic = YES;
The dynamic property decides if a sprite should be affected by physics forces.

Answer 3

you have written wrong code your pointOfView not affected by gravity you are just applying a small impusle on it.
change this line self.physicsWorld.gravity = CGVectorMake(0.0, 0.0) to self.physicsWorld.gravity = CGVectorMake(0.0, -9.8); if u looking for negative gravity towards up direction and CGVectorMake(0.0, 9.8) if you looking for positive gravity towards downwards. and try to apply impulse after a interval [pointOfView.physicsBody applyImpulse:CGVectorMake(10.0f, -10.0f)];