Lets Make a Mobile Game in 3-Weeks with Haxe & NME

I have decided that I would like to learn more about mobile game development. Its an exciting area of the games industry at the moment with so many frameworks and languages to choose from to develop with. The plethora of choice however can be a hindrance, what are the best frameworks and language for this particular task? Haxe with NME?  C# MonoTouch with Monogame? or even Javascript with Titanium? One can only go so far just reading about them, eventually you have to jump in and try them out for yourself.

So on that note I have decided to team up with an artist colleague (Moh ‘Mohzart’ Mukhtar) from work to create a mobile game in three weeks of evenings and weekends. Three weeks is an ambitious target for a game on any platform let alone mobile with its added complications. The primary purpose of this project however is to gather experience on the process of making mobile games using a given langauge, framework and platform. Having a longer time-scale I feel would deter from this, the primary motivation. Having said that however, I hope that in three weeks we will have something that to be reasonably proud of.

For this particular game I have decided to explore Haxe with NME. Haxe is a programming language I have been using for my personal projects for about a year now and is ideally suited to mobile development due to its ability to target multiple platforms with the same codebase. NME is a framework written in Haxe that emulates the Flash API and thus provides an interface I am extremely familiar with having used it for many years on personal and professional games. I dabbled with NME about a year ago while at the TryHarder conference however things have moved on with the project a lot since then and im looking forward to getting stuck in and playing around with it some more.

In theory Haxe with NME should give us the ability to target Flash, HTML5, OSX, Linux, Window, iOS, Android and WebOS all with the same codebase. I hope this to be the case, however, initially we will be focusing on getting it to run on Flash and iOS, the other platforms will be of secondary concern.

So as for the actual game itself. Over the last week or so we have been racking our brains trying to come up with a game that will be suitable for this project. To be suitable it must be achievable within three week, be compatible for touch based devices, suit both our skill sets and preferably not been done before on mobile. A tough set of requirements.

We wrote down a few ideas in a GDoc, but the best one and the one we have decided upon is to do a remake / variant on the “Chaos Emerald” bonus stage from Sonic1 on the Genesis. As a quick reminder of what that looks like:

It wont be a direct rip (before I have the Sega lawyers knocking down my door) but the inspiration will certainty come from that game. The reason why we finally chose this idea is because it should work quite well on mobile (single button press with accelerometer tilting) and is a fairly simple game code and art wise so hopefully we should be able to complete it within three weeks. As an added bonus I have been unable to find this already existing on the App Store. Let me know if you have seen it done already!

I intend to continue to update on the progress of the game as we go along on this blog 🙂

Fingers crossed we can pull it off!

On Porting RobotLegs2 & SwiftSupenders2 to Haxe

I originally hoped that this post would be about my successful completion of a RobotLegs2 port to Haxe however something else has come up (more on that in a later post) so instead im just going to talk about the process and progress of the port thus far.

So although there is already an excellent RobotLegs 1 Haxe port out there by David Peek, I decided I would like to try to port the brand new Robot Legs 2 Framework  which offers a great many improvements over the original.

Rather than beginning the port from scratch I decided to use as3hx to take the legwork out of converting the AS3 code to Haxe code. To get the tool you must first checkout the library from its google code repo at: http://caffeine-hx.googlecode.com/svn/trunk/projects/as3hx/

Once downloaded its just a simple matter of compiling the source into a neko executable:

[codesyntax lang=”powershell” lines=”normal”]

haxe as3hx.hx

[/codesyntax]

Then you can run it with:

[codesyntax lang=”powershell” lines=”normal”]

neko as3hx.n

[/codesyntax]

To convert a AS3 project give it an input and output folder:

[codesyntax lang=”powershell” lines=”normal”]

neko as3hx.n -vector2array -uint2int robotlegs2 robotlegs2out

[/codesyntax]

In this case the input folder is the source download from the RobotLegs2 GitHub page.

It will start to convert but will get stuck:

[codesyntax lang=”powershell” lines=”normal”]

C:/Users/MikeC/Desktop/as3hx/robotlegs2/src/robotlegs/bender/extensions/eventCommandMap/api/IEventCommandMap.as
C:/Users/MikeC/Desktop/as3hx/robotlegs2out/robotlegs/bender/extensions/eventcommandmap/api/IEventCommandMap.hx
C:/Users/MikeC/Desktop/as3hx/robotlegs2/src/robotlegs/bender/extensions/eventCommandMap/impl/EventCommandExecutor.as
C:/Users/MikeC/Desktop/as3hx/robotlegs2out/robotlegs/bender/extensions/eventcommandmap/impl/EventCommandExecutor.hx
C:/Users/MikeC/Desktop/as3hx/robotlegs2/src/robotlegs/bender/extensions/eventCommandMap/impl/EventCommandFactory.as
C:/Users/MikeC/Desktop/as3hx/robotlegs2out/robotlegs/bender/extensions/eventcommandmap/impl/EventCommandFactory.hx
C:/Users/MikeC/Desktop/as3hx/robotlegs2/src/robotlegs/bender/extensions/eventCommandMap/impl/EventCommandMap.as
C:/Users/MikeC/Desktop/as3hx/robotlegs2out/robotlegs/bender/extensions/eventcommandmap/impl/EventCommandMap.hx
C:/Users/MikeC/Desktop/as3hx/robotlegs2/src/robotlegs/bender/extensions/eventCommandMap/impl/EventCommandTrigger.as
Called from ? line 1
Called from Run.hx line 66
Called from Run.hx line 55
Called from Run.hx line 55
Called from Run.hx line 55
Called from Run.hx line 55
Called from Run.hx line 55
Called from Run.hx line 55
Called from Run.hx line 38
Called from C:Motion-TwinHaxe/std/neko/Lib.hx line 63
Called from Run.hx line 29
Called from as3hx/Parser.hx line 117
Called from as3hx/Parser.hx line 131
Called from as3hx/Parser.hx line 488
Called from as3hx/Parser.hx line 415
Called from as3hx/Parser.hx line 589
Called from as3hx/Parser.hx line 794
Called from as3hx/Parser.hx line 744
Called from as3hx/Parser.hx line 919
Called from as3hx/Parser.hx line 964
Called from as3hx/Parser.hx line 1106
Called from as3hx/Parser.hx line 1016
Called from as3hx/Parser.hx line 1075
Called from as3hx/Parser.hx line 1179
Called from as3hx/Parser.hx line 330
Called from as3hx/Parser.hx line 1003
Uncaught exception - In C:/Users/MikeC/Desktop/as3hx/robotlegs2/src/robotlegs/bender/extensions/eventCommandMap/impl/Eve
ntCommandTrigger.as(75) : Unexpected .

[/codesyntax]

It seems like as3hx is getting confused around this line in the AS3 source:

[codesyntax lang=”actionscript” lines=”normal”]

if (describeType(mapping.commandClass).factory.method.(@name == "execute").length() == 0)
				throw new Error("Command Class must expose an execute method");

[/codesyntax]

It looks like a bit of E4X is confusing the script. To solve this sort of problem I made a note of the location and file and just commented the offending line out. This allows as3hx to get past that particular snag. After going through this process a few times the project should be fully converted.

From there I setup a project in FlashDevelop and tried to compile. After fixing a few things that as3hx couldnt solve I came accross a rather major stumbling block.

RobotLegs2 unlike RL1 has a strong dependency on the dependency injection container SwiftSuspenders. So to get RL to compile I first need to port SwiftSupenders2.

So I repeated the process above but for SwiftSuspenders. Eventually this left me with a whole load of broken unit tests. Till Schneidereit the (rather splendid) author of SwiftSuspenders wrote a great number of unit tests for the library, which is one of the reasons why its so excellent. So I knew that to achieve a proper port all I need do is pass all those tests and I can then be confident that the code is solid.

After a few evenings of toil I managed to get 50 tests to pass in the Flash target. This is quite abit shy of the 160+ tests in the original AS3 version of the library, however a great many of those tests are not relevant to Haxe such as ArrayCollection tests, XML tests and DescribeType tests. I also decided for now to remove all of the event dispatching (and thus their tests) code from the library for now due to their dependency on the Flash platform. Despite this I think the 50 tests that do pass are probably representative of the core functionality of the library.

With the Flash target passing I indented to then move onto passing the tests in the other targets (JS, C++, php etc). I was hoping that with the flash part passing that they would all pass considering that im using the inbuilt haxe reflection methods not any platform specific reflection, but alas this was not to be the case. Starting with the JS target I started to get alot of errors on some of the basic Injector tests. After some digging in the compiled JS source I traced it back to an issue in the Meta Data generation for the @Inject tag on the JS target.

Unfortunately, I have run out of time on this little side project for now so am going to have to park it. I have uploaded the progress thus far to GitHub should anyone else wish to take up the mantle on the port:

https://github.com/mikecann/SwiftSuspendersHx
https://github.com/mikecann/RobotLegs2Hx

I had indented, once everything was passing, was to do a branch of the project and incorporate some features that only the Haxe language can support. Features such as proper generics and macros would bring some added awesome.

Malaysia 2012

For the past two weeks I have been travelling about Malaysia seeing a very small chunk of what there is to see there.

We started in Kuching on the Borneo island part of Malaysia, we went Kayaking down the bang-bang river:

And checked out some Orangutans in the jungle:

From here we took a short flight to Singapore, where we explored the city for a couple of days:

From Singapore we took a bus journey to Mersing then a (horrific) ferry ride to the beautiful island of Tioman:

The island itself was beautiful with lush jungles, stunning waterfalls and pristine coral snorkalling:

To wrap up our short visit to Malaysia we headed over to Kuala Lumpur:

And that sadly was the end of our journey, what better way to spend the last evening then in the Traders Tower Sky Bar with a view over to the Petronas Towers: