Friday, 2 July 2010

How to write a great 2D iphone game in a few days

Further to my last post, I thought I'd share some great resources I've found for developing 2D games in virtually no time.

cocos2d for iPhone is a good starting point, especially if you base your game on an existing code base such as TweeJump (see previous post). This gives you something working in minutes.

For PoodleJump, I needed to enhance and customise the game with 2 key elements which aren't that easy to generate from scratch: images and sounds. TweeJump has no sounds which is a real shame, and by adding some carefully chosen sounds, I think I've really improved the enjoyment factor. Also, simply by changing a few small images, I've got a completely new game.

For Mac users (and that means all iPhone developers, for now), GarageBand is a great tool. I used it to generate a fairly cool soundtrack for TractorBeams and DarkFlow (ok, so I need to produce some new tunes). For someone as musically challenged as me, it's surprisingly easy to put loops together to produce something quite professional sounding. And yes, the loops are royalty free so the produced song can be used in commercial projects.

But GarageBand also has hundreds of great quality sound effects. I also highly recommend freeSFX for free samples.

Note: for short sound effects, you really want to save in WAV format (iTunes can convert it for you) and use AudioServicesPlaySystemSound to play it, which results in no lag or graphical glitches, unlike AVAudioPlayer.

What about images? There's lots of sites out there but a particularly good one I found was graphicsfactory. They have a large quantity of quality images and offer one free download per day. Perfect for my limited requirements.

Gimp of course is great for tweaking images and putting texture maps together. It's also cross platform and free.

The end result was a complete game in about 7 days with zero cost. Let's see how much revenue those iAds generate.


I'm working on a new game! It's called PoodleJump and it's very cool. It's cool for lots of reasons.

It's obviously inspired by a well known iPhone game, but this one will be free, and supported by iAds.

It also incorporates Facebook integration, which allows you to submit your score to your Facebook wall. Should be good for some viral marketing.

Perhaps the best thing about PoodleJump is that it's taken me less than a week to write. How come? It uses shared code from the open source game, TweeJump, which is itself using the cocos2d for iPhone library.

This is quite a departure for nugames (and for me). It's our first 2D game and I'm really enjoying the short development cycle - expect to see lots more 2D games coming your way over the coming months. At least one a month is my target.

In my experience, Facebook posts seem to generate quite a lot of buzz so it'll be interesting to see what effect this has on my app marketing. I think the combination of rapid fire 2D development, plus Facebook viral marketing and iAd support in free apps could be a real winner. For the first time I'm also directly linking to previous games right from the app, plus this blog. Should boost my readership over the coming months.

I hope to submit this one to the app store in the next few days.

DarkFlow HD in review - and iAd UK Launch date

Quick update: DarkFlow HD is now being reviewed by iTunes staff.

Due to the launch of iAd yesterday, I'm expecting additional scrutiny to ensure the iAd functionality in my app is up to Apple's standards, therefore it could easily remain in review for most of next week.

Speaking of iAd, if you have recently purchased an iPhone4 or upgraded your existing device to iOS4 and are watching out for iAds to start appearing, the UK launch date is set for September (according to this). iAd in the US launched yesterday (1st July) and ads for the Nissan Leaf electric vehicle (as trailed by Steve Jobs) have been spotted in the wild.