I found an awesome tip in the following post, Strange lines appears during sprite movement, in the Cocos2D forums. Depending if the problem occurs due to the background or foreground, you either have to extrude or add padding to your sprites.

When you extrude, you simply repeat the same pixels around the tiles without adding them directly to the sprite. Extruding actually helped me fix my problem. Padding seems to just separate the sprites from each other. If you notice sprites leaking nearby sprites on the sprite sheet, padding should solve this problem.

After learning about this, I fired up Zwoptex, selected all my sprites, and added about 1px to the Extrude option.

After that, I started my game and was able to see that strange line effect gone!

If you use Texture Packer you have the same option.

Resource – Strange lines appears during sprite movement

I started by simply grabbing a book. The following are some good ones: Cocos2d for iPhone 1 Game Development Cookbook
(Official), Learning Cocos2D: A Hands-On Guide to Building iOS Games with Cocos2D, Box2D, and Chipmunk, and Learn cocos2d Game Development with iOS 5 (one I started with). If you don’t mind spending money on a good resource, try it out and you could have your first game within reading the first few chapters (1-3hours!). You could even start with Cocos2D Programming Guide if you aren’t convinced and don’t want to spend money yet.

The thing is, the books only cover so much and really don’t go in depth with other things that might arise in your game development journey. A lot of unprecedented things occurred in mine such as how to find the right team, idea for a game, community to give opinions about my project, how to set up deadlines and complete them, amongst other topics.

That is why I decided to share with you all the things I’ve learned along the way in making my game such as all the things I’ve hated, loved, and even code samples for how I got things done within a game such as level creation/editing, collision detection, how to make a hero, etc. If there is anything in particular you want me to cover, please let me know and I’ll do my best to either answer in the comments or even make a post about it.

If you are interested in following my current marketing efforts become a fan of Feed the Dragons on Facebook. It was barely set up a few days ago so be patient for now. If you want to know the gist of my game, it’s simply Multiplayer Snake for iPad (up to 4 players). If you ever played Nibbles, then you have an idea of where I got my inspiration. I’m basing the gameplay off that game by having a couple of friends either cooperatively or competitively playing a game on one device. It may sound difficult, but trust me, it’s a blast and we hope you believe the same when we decide to publish our game in the next few months.

Our next post will probably be something like “So can I start making video games, and how?”. I’ll be covering how much you really need to know, the things you should consider, and how to start!