haXe preloader

2 years ago I tried to create a preloader in haXe, but whatever I tried, nothing worked. Today, I had to create a preloader for a project at work. Needless to say, I wasn’t too happy, with that first experience in mind.

I did some Googling and found various forum and blog posts, but whatever I tried, nothing seemed to work. Mindless Labs suggested using mxmlc to embed the game .swf into an Actionscript preloader, but mxmlc couldn’t digest our game .swf. Game Haxe had another approach, but apparently that one broke when haXe 2.03 got released. Using the MochiAd preloader didn’t work out of the box either, because that one would only be run after the whole .swf was loaded. So I was thinking towards creating a separate preloader .swf that would load the main game .swf – it’s a messy, multi-file solution, but at least it’s a solution.

However, I talked about it to a coworker, asking how this would be done in ActionScript. The standard approach is to move all assets to a later frame, and to put some preloader code and assets in the first frame. I decided to give it a try – mind you, the same thing had failed me 2 years ago – and suprizingly, it worked! Back then, the assets had been inaccessible, but some haXe and swfmill versions later it works like a charm.

Here’s how my swfmill .xml file looks like now:

<?xml version="1.0" encoding="iso-8859-1" ?>
<movie version="9" width="600" height="400" framerate="30">
    <background color="#FFFFFF"/>
    <frame /> <!-- add one empty frame -->
    <frame>
        <library>
            <clip id='image' import='images/image.png' />
            <font name='font' import='fonts/font.ttf' />
        </library>
    </frame>
</movie>

Line 4 is important: it adds an empty frame, into which the haXe code is compiled. The second frame contains all the heavy-duty assets, which will be available once the whole .swf has been downloaded.

My main function now looks like this:

package ;
import flash.events.Event;
import flash.Lib;
import haxe.Log;
import game.Game;

class Main
{
    static function main()
    {
        Log.trace("Starting preloader");
        Lib.current.root.addEventListener(Event.ENTER_FRAME, onEnterFrame);
    }
    
    static function onEnterFrame(event : Event)
    {
        Log.trace("Downloaded " + Lib.current.root.loaderInfo.bytesLoaded + " of " + Lib.current.root.loaderInfo.bytesTotal + " bytes");
        
        if (Lib.current.root.loaderInfo.bytesLoaded >= Lib.current.root.loaderInfo.bytesTotal)
        {
            Lib.current.root.removeEventListener(Event.ENTER_FRAME, onEnterFrame);
            Log.trace("Preloading finished");
            
            // The Game class adds images to the screen, sets up listeners, etc.
            var gameInstance : Game = new Game();
        }
    }
}

Normally, I would’ve created a Game instance immediately within the main function, but the assets only become available once the whole .swf is loaded, so it’s a smart idea to wait until the number of bytes loaded matches the total number of bytes. ;)

I hope this post is useful to those who are looking for a haXe preloader. :)

<?xml version=”1.0″ encoding=”iso-8859-1″ ?>
<movie version=”9″ width=”600″ height=”400″ framerate=”30″>
<background color=”#FFFFFF”/>
<frame /> <!– add one empty frame –>
<frame>
<library>
<clip id=’image’ import=’images/image.png’ />
<font name=’font’ import=’fonts/font.ttf’ />
</library>
</frame>
</movie>
haXe preloader

MochiAds in haXe

I’ve been using haXe at work for a current project, and while things have been working pretty well so far, one thing proved to be a little more troublesome than we expected. We tried integrating MochiAds highscore APIĀ  into the game, following hesselboom’s guide, but whatever we did, all we got was a broken game. No MochiAd pre-game ad, nothing, just a white screen. That’s not a good thing, considering that integrating it into an Actionscript project is supposedly a 5-minute job.

To give a little more insight, all game assets are packed into a .swf file using swfmill. The process is automated with a Python script, so all images, sounds and fonts are lumped together into archive.swf. When compiling the haXe code, this .swf file is passed along, so the code gets compiled into the .swf, to produce the final game .swf. Hesselboom’s guide suggested embedding the mochi library and the assets .swfs into one archive .swf. We first tried to just embed the mochi library .swf into our archive .swf, but that didn’t work. We then tried embedding both into a new .swf, but that didn’t work either.

My coworker did get MochiAds working in a new project though, just not in the actual game. So I started analyzing the swfmill output and I noticed something interesting. The fonts were giving trouble. Apparently swfmill can’t handle the case where an embedded .swf file contains already embedded fonts. However, embedding the fonts into the final .swf didn’t solve the problem…

In the end, I tried something silly: changing the embedding order of the library and the assets .swf. Guess what? It worked!

So just in case you’re working with haXe and integrating MochiAds fails – swapping two lines in your swfmill xml file might just do the trick. :)

MochiAds in haXe

Bullet consumption

I’ve been prototyping yet another game idea during the last few weeks. Since I’m now a full-time game programmer at Triangle Studios, I have less spare time to devote to game-development. Fortunately, less doesn’t mean nothing at all.

So here’s BulletEater. A danmaku/bullet-hell game. Except that you’re unable to fire back at turrets, so you’ll just have to survive the bullet patterns. Actually, you’re not completely defenseless: there’s an overcharge mode that allows you to eat bullets, which in turn adds to your score. It does cost you a life however, but lives slowly recharge so that’s simply a matter of surviving long enough. Eating bullets speeds up the recharge process a bit so you may want to save your lives for the really nasty situations.

Bullet Eater - danmaku mayhem

These are things I’m still thinking about, as they make large bullet patterns easy score-fests instead. So I’m thinking about including laser-beams that can’t be eaten to control the difficulty and challenge some more. If you have any suggestions, feel free to share them.

Bullet consumption

AI Wars released

I intended to release AI Wars last week, but some things got in the way. Some people have been asking me about it recently though, so I contacted my friend Inky for the latest version of his AI client and wrapped it all up in a .rar file:

Blue tank AI Wars download (210 kB)

The package contains the server and an AI client, written by Inky. Startup instructions can be found in the readme.txt file. If you’re interested in writing your own AI clients, contact me on this blog or through my portfolio’s contact page and I’ll settle some documentation and code.

Thanks to Mark, who worked with me on the AI Wars server, and Siebe, who built the AI client. And thanks to Jaco and Vassili for their emotional support, of course. Hehe. happy.gif

Anyway, enjoy, and please let me know what you think of AI Wars. happy.gif

AI Wars released

Checking out Neko Media Engine

I recently stumbled across Neko Media Engine, a SDL wrapper for haXe. I decided to port one of my Flash games to NME, to make it a stand-alone application. I got it up and running after modifying my framework for a few hours. It turns out that, with relatively few changes, my framework can be used for ‘normal’ games just as well. I’m starting to like haXe more and more now, especially with such libraries around.

The developer of NME, Lee Sylvester, has recently teamed up with Hugh Sanderson to create Neash: a Neko library that provides the Flash API for Neko applications. In other words, we’ll be able to use (almost) the same haXe code for both Flash and Neko applications… That sounds interesting!

Checking out Neko Media Engine

Final internship has started…

Last week I started with my final internship. It’s, again, at Triangle Studios. This time, there’s no mobile games to work on though, but Nintendo DS titles. I’m working on something pretty interesting, but for now that’s about as much as I can tell.

As for spare-time development, I plan to release AI Wars next week after some minor fix-ups. I’m then going to continue work on the surprize I mentioned last month. After that, I’ll either do another small project in-between or I’ll immediatly take up work on Aural Fighter.

The framework I’ve been building for Aural Fighter has been tweaked and refactored all the way through AI Wars, the surprize project and a few other prototypes. I recently streamlined the rendering system: animated sprites are now simply a matter of creating a single sprite sheet and writing an animation data text file, rather than creating multiple numbered files. At compile-time, this animation data is compiled into the .swf file. The sprite loading process then attaches that data to the loaded sprite. There are still a few things I’m working on, such as color remapping and fading filters, but the framework is steadily moving towards a point where creating new games doesn’t require me to add new functionality anymore. Which means I can focus more on the actual games and less on the technology behind them. Which is good. smile.gif

Final internship has started…

AI Wars is looking for AI agents!

AI Wars is done

It’s finished. The Flash frontend and Neko backend are done, and my classmates have produced a nice AI client for demonstration purposes. The whole package is roughly 0.5 MB.

AI Wars - blue versus yellow

To make things a little easier, I’ve written a batch file that starts both the backend and the frontend. All that’s left then is connecting the AI clients and starting the game.

The gameplay

Continue reading “AI Wars is looking for AI agents!”

AI Wars is looking for AI agents!