Question

i am using cocos2d and having many sprites and bodies. each sprite has its body, and each kind of sprite has a tag. (see next) .

when 2 sprites are contact each other, i can discover that and i want them to disappear.

THE problem is that i have many sprites from the same kind(having the same tag) so when i clean a sprite, it does clean the last sprite that was created and not the one i want.

my function that create a sprites from the same kind is :

-(void)fruit1:(int) randomForCoordinates
{

    //define sprite
    fruit1=[CCSprite spriteWithFile:@"fruit1.png"];
    fruit1.tag=2;
    fruit1.position=ccp(randomForCoordinates,500);
    //add fruit
    b2BodyDef spriteBodyDef;
    spriteBodyDef.type =b2_dynamicBody;
    spriteBodyDef.position.Set(fruit1.position.x/PTM_RATIO,fruit1.position.y/PTM_RATIO);
    spriteBodyDef.userData = fruit1;
    fruit1body = world->CreateBody(&spriteBodyDef);

    b2PolygonShape spriteShape; //b2polygon-for box shape
    spriteShape.SetAsBox(fruit1.contentSize.width/PTM_RATIO/2,fruit1.contentSize.height/PTM_RATIO/2); //for b2polygon
    b2FixtureDef spriteShapeDef;
    spriteShapeDef.shape = &spriteShape;
    spriteShapeDef.density = 10.0;
    spriteShapeDef.isSensor = false;
    fruit1body->CreateFixture(&spriteShapeDef);
    [self addChild:fruit1];

}

which is tagged as 2.
when i see a contact with this :

//cotact listener 
    std::vector<MyContact>::iterator pos;
    for(pos = _contactListener->_contacts.begin(); pos != _contactListener->_contacts.end(); ++pos) 
    {
        MyContact contact = *pos;
        b2Body *bodyA=contact.fixtureA->GetBody();
        b2Body *bodyB=contact.fixtureB->GetBody();

        //check if collision between to bodies
        if( bodyA->GetUserData() !=NULL && bodyB->GetUserData() !=NULL)    //if ((contact.fixtureA == _bottomFixture && contact.fixtureB == _ballFixture) ||(contact.fixtureA == _ballFixture && contact.fixtureB == _bottomFixture))
        {
            CCSprite *actor = (CCSprite*)bodyA->GetUserData(); 
            CCSprite *actorb = (CCSprite*)bodyB->GetUserData();


            //touch
            if ([actorb tag] == 2  && [actor tag]== 1)
            {
            [fruit1.parent removeChild:fruit1 cleanup:YES];
            NSLog(@"touch1");

            }

now the sprite that disappear is not that one that touched here, but the one that was created after him ..

HOW can i erase a SPECIFIC sprite-the one that just touched another one ??
not the LAST one created ?

thanks a lot

Answer 1

If two sprites are Collide you remove any one like below:

 if( bodyA->GetUserData() !=NULL && bodyB->GetUserData() !=NULL)    //if ((contact.fixtureA == _bottomFixture && contact.fixtureB == _ballFixture) ||(contact.fixtureA == _ballFixture && contact.fixtureB == _bottomFixture))
    {
        CCSprite *actor = (CCSprite*)bodyA->GetUserData(); 
        CCSprite *actorb = (CCSprite*)bodyB->GetUserData();


        //touch
        if ([actorb tag] == 2  && [actor tag]== 1)
        {

            [self removeChild:actor cleanup:YES];
            //(or)
            [self removeChild:actorb cleanup:YES];


        NSLog(@"touch1");

        }