適應不同的設備

        CCSpriteBatchNode *chapter2SpriteBatchNode;
        if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
            [[CCSpriteFrameCache sharedSpriteFrameCache]  addSpriteFramesWithFile:@"scene1atlas.plist"]; // 3.1
            chapter2SpriteBatchNode = [CCSpriteBatchNode  batchNodeWithFile:@"scene1atlas.png"]; // 3.2
        } else {
            [[CCSpriteFrameCache sharedSpriteFrameCache]  addSpriteFramesWithFile:@"scene1atlasiPhone.plist"];// 3.1
            chapter2SpriteBatchNode = [CCSpriteBatchNode  batchNodeWithFile:@"scene1atlasiPhone.png"]; // 3.2
        }