I'm a novice of cocos2d.
I developer a game like flappy bird following the tutorial:
The game was fine and everything worked well as expected but after I upgraded SpriteBuiler to version 1.2.1 (so it updated also cocos2d library) the fly/bird slowly moves to the left, and after a short amount of time it slowly disappears on the left side of the screen.
I tried to debug and found that this behavior is caused by the applyAngularImpulse methods: one called when no touches are detected after an amount of time (fly/bird rotates and falls down) and another when touches are detected (fly/bird rotates and goes up).
If I comment these two lines the problem disappears but the fly/bird remains always in the horizontal static position not showing the effect of rising up and drop down.
Another question: where can I read, study and learn (not only following a tutorial) how to develop good games (for iOS and Android) and learn also physics? What are the most effective and productive books, pdf and websites?.