Soft-Body Physics - Learn SpriteBuilder for iOS Game Development - page 334

_playerNode = center;
_softBodyPlayer = YES;

}
CGPoint offset = (_softBodyPlayer ?
_playerNode.parent.positionInPoints

: CGPointZero);
[self scrollToTarget:_playerNode withOffset:offset];

}

If the _playerNode has children, which is only the case for the new soft-body player
object, the first object replaces the _playerNode reference. This makes the soft-body
player's center node the new _playerNode . The _softBodyPlayer ivar is set to
YES to indicate that this level is using the soft-body player.
The scrollToTarget: method will be updated shortly. Here in Listing 10-5 , the new
version is already being called. The new version takes an offset parameter to account
for the fact that the center node's position is an offset to its parent position rather than be-
ing in-scene coordinates.
Locate the update: method in GameScene.m . It also needs to be updated with the
changes highlighted in Listing 10-6 .

Listing 10-6 . Accelerating all bodies and scrolling with offset

-(void) update:(CCTime)delta
{

if (_acceleratePlayer)
{

if (_softBodyPlayer)
{

for (CCNode* node in
_playerNode.parent.children)
{

[self accelerateTarget:node];

}

}
else
{

[self accelerateTarget:_playerNode];