Cocos2D - Detecting collision - objective-c

Question

I am a beginner in cocos2d and im facing a problem with detecting collision for my coins.
Sometimes it works sometimes it doesn't.
So basically, im creating a game which the user (ship) have to avoid the obstacles and collect coins on the way. The collision of the obstacle works well but not for the coins.
I was thinking maybe the loops for creating many coins is the problem but im not sure.
Can anyone help?
My codes:
- (void)update:(ccTime)dt{
double curTime = CACurrentMediaTime();
if (curTime > _nextBridgeSpawn) {
float randSecs = [self randomValueBetween:3.0 andValue:5.0];
_nextBridgeSpawn = randSecs + curTime;
float randX = [self randomValueBetween:50 andValue:500];
float randDuration = [self randomValueBetween:8.0 andValue:10.0];
CCSprite *bridge = [_bridge objectAtIndex:_nextBridge];
_nextBridge++;
if (_nextBridge >= _bridge.count) _nextBridge = 0;
[bridge stopAllActions];
bridge.position = ccp(winSize.width/2, winSize.height);
bridge.visible = YES;
[bridge runAction:[CCSequence actions:
[CCMoveBy actionWithDuration:randDuration position:ccp(0, -winSize.height)],
[CCCallFuncN actionWithTarget:self selector:#selector(setInvisible:)],
nil]];
this is where i declare my coins (continued from the update method)
int randCoin = [self randomValueBetween:0 andValue:5];
_coin = [[CCArray alloc] initWithCapacity:randCoin];
for(int i = 0; i < randCoin; ++i) {
coin = [CCSprite spriteWithFile:#"coin.png"];
coin.visible = NO;
[self addChild:coin];
[_coin addObject:coin];
}
float randCoinX = [self randomValueBetween:winSize.width/5 andValue:winSize.width - (border.contentSize.width *2)];
float randCoinY = [self randomValueBetween:100 andValue:700];
float randCoinPlace = [self randomValueBetween:30 andValue:60];
for (int i = 0; i < _coin.count; ++i) {
CCSprite *coin2 = [_coin objectAtIndex:i];
coin2.position = ccp(randCoinX, (bridge.position.y + randCoinY) + (randCoinPlace *i));
coin2.visible = YES;
[coin2 runAction:[CCSequence actions:
[CCMoveBy actionWithDuration:randDuration position:ccp(0, -winSize.height-2000)],
[CCCallFuncN actionWithTarget:self selector:#selector(setInvisible:)],
nil]];
}
}
this is to check for collision (also in the update method)
for (CCSprite *bridge in _bridge) {
if (!bridge.visible) continue;
if (CGRectIntersectsRect(ship.boundingBox, bridge.boundingBox)){
bridge.visible = NO;
[ship runAction:[CCBlink actionWithDuration:1.0 blinks:5]];
}
}
}
//this is the collision for coins which only work at times
for (CCSprite *coin2 in _coin) {
if (!coin2.visible) continue;
if (CGRectIntersectsRect(ship.boundingBox, coin2.boundingBox)) {
NSLog(#"Coin collected");
coin2.visible = NO;
}
}
}
Thank you.

Answer 1

Why you just don't check distances?
float dist = ccpDistance(ship.position, coin2.position);
float allowedDist = ship.contentSize.width*0.5 + coin2.contentSize.width*0.5;
if (dist<allowedDist){
NSLog(#"Collision detected");
}
If your sprites are not on the same layer, these layers should have at least same positions.

Answer 2

what is phone in the last piece of code? you check there if it's boundingBox intersects coins one, but I cannot see it anywhere else. Another one, boundingBox will work only if your objects have the same parent, because it returns "local" rect, relatieve to it's parent
another one point is that in case of too fast movement speed of your objects it is possible, that they will pass throw each other during tick time. I mean, that one update will be called before collision, so it will not detect it and the next one will be called after collision was finished, so it will not detect it either.

Answer 3

I've solved my problem by creating a timer in init and call it every 10 secs to create my coins.
My codes:
-(void) createCoins:(ccTime)delta{
CGSize winSize = [CCDirector sharedDirector].winSize;
int randCoin = [self randomValueBetween:0 andValue:10];
_coin = [[CCArray alloc] initWithCapacity:randCoin];
for(int i = 0; i < randCoin; i++) {
coin = [CCSprite spriteWithFile:#"coin30p.png"];
coin.visible = NO;
[self addChild:coin];
[_coin addObject:coin];
}
float randCoinX = [self randomValueBetween:winSize.width/5 andValue:winSize.width - (border.contentSize.width *2)];
float randCoinY = [self randomValueBetween:100 andValue:700];
float randCoinPlace = [self randomValueBetween:30 andValue:60];
for (int i = 0; i < _coin.count; i++) {
CCSprite *coin2 = [_coin objectAtIndex:i];
coin2.position = ccp(randCoinX, (winSize.height + randCoinY) + (randCoinPlace *i));
coin2.visible = YES;
[coin2 runAction:[CCSequence actions:
[CCMoveBy actionWithDuration:8 position:ccp(0, -winSize.height-2000)],
[CCCallFuncN actionWithTarget:self selector:#selector(setInvisible:)],
nil]];
}
}
in the update method:
for (CCSprite *coins in _coin){
if (!coins.visible) continue;
if (CGRectIntersectsRect(phone.boundingBox, coins.boundingBox)) {
NSLog(#"Coin collected");
coins.visible = NO;
}
}
Thank you everyone for the help(: