Vellios.com A single Dad and his son living the life you never knew existed...

-(id) init {
//... Add at end of init after body->CreateFixture(&fixtureDef);
	// Create our static "Planet"
	b2CircleShape shape;
	shape.m_radius = 1.0f;
	shape.m_p.Set(8.0f, 8.0f);
	b2FixtureDef fd;
	fd.shape = &shape;
	planet = groundBody->CreateFixture(&fd);
}
 
-(void) tick: (ccTime) dt
{
	int32 velocityIterations = 8;
	int32 positionIterations = 1;
 
	world->Step(dt, velocityIterations, positionIterations);
 
	for (b2Body* b = world->GetBodyList(); b; b = b->GetNext())
	{
		b2Body* ground = planet->GetBody();
		b2CircleShape* circle = (b2CircleShape*)planet->GetShape();
		// Get position of our "Planet"
		b2Vec2 center = ground->GetWorldPoint(circle->m_p);
		// Get position of our current body in the iteration
		b2Vec2 position = b->GetPosition();
		// Get the distance between the two objects.
		b2Vec2 d = center - position;
		// The further away the objects are, the weaker the gravitational force is
		float force = 250.0f / d.LengthSquared(); // 150 can be changed to adjust the amount of force
		d.Normalize();
		b2Vec2 F = force * d;
		// Finally apply a force on the body in the direction of the "Planet"
		b->ApplyForce(F, position);
 
		if (b->GetUserData() != NULL) {
			CCSprite *myActor = (CCSprite*)b->GetUserData();
			myActor.position = CGPointMake( b->GetPosition().x * PTM_RATIO, b->GetPosition().y * PTM_RATIO);
			myActor.rotation = -1 * CC_RADIANS_TO_DEGREES(b->GetAngle());
		}	
	}
}

@interface HelloWorld : CCLayer
{
	b2World* world;
	GLESDebugDraw *m_debugDraw;
	b2Fixture* planet; // This will be a static body
}