NewCCBAnimationManager.m

-(void) startWithTarget:(CCNode *)aTarget
{
    [super startWithTarget:aTarget];
    
    NSAssert([self.target isKindOfClass:[CCNode class]], @"Target is not CCNode");
    
    startAngle_ = [(CCNode *)self.target rotation];
    diffAngle_ = dstAngle_ - startAngle_;
}

-(void) update: (ccTime) t
{
    NSAssert([self.target isKindOfClass:[CCNode class]], @"Target is not CCNode");
    
    [(CCNode *)self.target setRotation: startAngle_ + diffAngle_ * t];
}