Adding UIImage to CCSprite using Box2D

Question

I want to add an image to a CCSprite and then use that inside my Box2d world. The createBoxAtLocation picks up the contentSize correctly but never displays the image...what am I doing wrong? Do I need to add anything to the update() function?

    CCSprite *sprite = [CCSprite spriteWithFile:@"slider_piece.png"];

    [self createBoxAtLocation:loc1 withSize:boxSize forSprite:sprite];


    -(void) createBoxAtLocation:(CGPoint)location withSize:(CGSize)size forSprite:(CCSprite *)_sprite
    {   
        b2BodyDef bodyDef;
        bodyDef.type = b2_dynamicBody;
        bodyDef.position = b2Vec2(location.x/PTM_RATIO, location.y/PTM_RATIO);
        bodyDef.allowSleep = false;
        //bodyDef.userData = _sprite;

        b2Body *body = world->CreateBody(&bodyDef);
        body->SetUserData(_sprite);

        b2FixtureDef fixtureDef;

        b2PolygonShape shape;
        shape.SetAsBox(_sprite.contentSize.width/2/PTM_RATIO, _sprite.contentSize.height/2/PTM_RATIO); 
        fixtureDef.shape = &shape;   

        body->CreateFixture(&fixtureDef);    
    }

EDIT

Inside the update function I have this, but it causes a EXC_BAD_ACCESS error on sprite.position line

    for(b2Body *b = world->GetBodyList(); b != NULL; b = b->GetNext()) 
   {    
      if (b->GetUserData() != NULL) {
           CCSprite *sprite = (CCSprite *) b->GetUserData();
           sprite.position = ccp(b->GetPosition().x * PTM_RATIO, b->GetPosition().y * PTM_RATIO);
           sprite.rotation = CC_RADIANS_TO_DEGREES(b->GetAngle() * -1);
       }       
   }

Kazuki Sakamoto Kazuki Sakamoto · Accepted Answer · 2011-07-28T04:56:20

The sprite is not addChild'ed to any CCNode(CCLayer or CCScene or so forth)?

If so,

CCSprite *sprite = [CCSprite spriteWithFile:@"slider_piece.png"];

the sprite might be released in update() because the sprite is autoreleased object.

You have to retain the sprite in this case at CreateBody,

body->SetUserData([_sprite retain]);

And then release it at DestroyBody.

[(CCSprite *)body->GetUserData() release];

BTW, I recommend you to use CCBox2D.

EDITED:

Did you addChild the sprite to your CCScene or child nodes?

[self addChild:sprite];

Or the body's position (loc1) is in the screen range?

Adding UIImage to CCSprite using Box2D

1 Answers