Lets start with a reply to the original article. Some while after the article was published on .simplicity Valentin Anastase from the non-profit organization Freezing Moon replied. He provided a link to two sites, including Freezing Moon’s, dedicated to free gaming. Freezing Moon comes close to the idea that I sketched in the previous article, but it is not completely the same. Opposed to the Free Gaming Alliance, Freezing Moon actually develops games themselves. While I think that we should first deal with other issues concerning free gaming, I am happy to see an initiative like Freezing Moon and I encourage people to check it out.

Another interesting development can be found at OpenGameArt.org. OpenGameArt.org is a website that hosts “free, legal art for open source game projects”. It started small, but the amount of art has been growing fast. And the art that is being hosted on OpenGameArt.org is certainly not bad; it looks very good. If you are looking for art for your Free Open Source Game or want to support free game art (OpenGameArt.org accepts donations), then definitely check OpenGameArt.org.

So, there are initiatives focused on Free Open Source Gaming, but what about me? Through Sirrf I am trying to improve the Free Open Source Gaming ecosystem. I am wondering if I can have an impact on it in other ways, though.

The first project that you can find on .simplicity Code is the .simplicity Java Sigslot Event System. This is, as the name already says, an implementation of a sigslot event system in Java. A sigslot event system allows the programmer to connect components within a system without that those components know with who they are actually connected. Furthermore this system can also be used as a broadcasting system for sending information to multiple subscribed components. Sigslot event systems can be applied in various different cases, such as component-based entity systems and graphical user interfaces.

But lets look at some example code using the .simplicity Java SigSlot Event System:

// Import classes
import java.applet.Applet;

import java.awt.Graphics;
import java.awt.event.*;

import net.dotsimplicity.events.awt.AWTEventsContainer;

// EventApplet class
public class EventApplet extends Applet
{
    // Public methods
    // Initialize the applet.
    public void init()
    {
       // Create an AWT EventsContainer.
       AWTEventsContainer container = new AWTEventsContainer("applet", this);

       // Add a mouse moved event.
       container.addMouseMotionListener();
       container.connectEventSlot("mouseMoved", this, "onMouseMoved");

       // Add a custom event.
       container.createEvent("print", String.class);
       container.connectEventSlot("print", this, "onPrint");
       container.emitEventSignal("print", "Hello, World!");
    }

    // Paint the applet.
    public void paint(Graphics g)
    {
       g.drawString("X: " + this.x + ", Y: " + this.y, 10, 15);
       g.drawString(this.message, 10, 30);
    }

    // Handle mouseMoved events.
    public void onMouseMoved(MouseEvent event)
    {
       this.x = event.getX();
       this.y = event.getY();
       this.repaint();
    }

    // Handle print events.
    public void onPrint(String string)
    {
       this.message = string;
    }

    // Private members
    private static final long serialVersionUID = 1;
    private int x, y;
    private String message;
}

// End of File

In the above example we have created an applet that uses our sigslot event system to handle mouseMoved events. Please note that we do not have to implement the MouseMotionListener interface; you are free to only implement those features that you need under whatever name you choose. That means that you no longer have to implement six empty methods if you want to use one feature of the WindowListener, for example.

Furthermore we also use our event system to transmit a signal with the message “Hello, World!”. In this particular appliance this is a rather useless operation, but it demonstrates in a simple way how we can use our system for broadcasting. Note that you can also use the relatively simpler EventsContainer for this appliance; this class provides all methods that the AWTEventsContainer provides except for the AWT specific methods.

Well, that is all for now. We hope that .simplicity Code will be of use to you.

• Script-side GameStates
  It is now truely possible to derive from the GameState class (through CGameState) in scripts. A bug in previous versions prevented this, but this bug has now been fixed.
• Script-side Components
  EntityComponent can be derived from script-side (through CEntityComponent), classes in script can now create components and register them with entities from script or engine side.
• Script-side Events
  The event system is now integrated into the script engine. Script-side classes can derive from IHasSlots and can register, connect and disconnect from slot events.
• Important Bug Fixes:
  • Construction of entity components with parent is now relatively safe. If you are not sure whether your component has a parent, check it after construction. If the component has no parent, destroy it as quickly as possible
  • AssetProcessors on windows were never loading assets unless the files were all lowercase, restrictions were irrlicht related but solved.
  • Minor bug fixes with script side things, Scolor fixes, asset groups on entities and much much more.

Useful links
SourceForge.net page – http://sourceforge.net/projects/sirrf
Downloads – http://sourceforge.net/projects/sirrf/files/ | http://www.ohloh.net/p/sirrf/download?package=Sirrf
Documentation – API | Tutorials

• Asset Management
  The biggest new feature is asset management. Assets are managed by the AssetManager class. This manager manages so-called asset groups, which represent a collection of assets (meshes, textures, etc). These assets are retrieved from a directory with the appropriate directory structure. In turn the found assets are processed by asset processors. And at the end of the road, the user can use these assets without having to deal with paths. Furthermore asset management makes it possible to reload all assets in realtime, with direct results on the current scene. Reloading assets is as simple as one function call.
• XML-based Entity files
  It is now possible to load data concerning entities and their components from XML-files. This means that you can now define a scene through XML-files.
• Local Event System
  As of version 0.2.0 a HasEvents class, which provides the base for a local event system, is available. The availability of local event systems makes the entire framework more performant. Currently the HasEvents class is used by entities and asset groups.
• Microsoft Visual C++ 2008 support
  Version 0.2.0 is the first release that officialy supports Microsoft Visual C++ 2008. This should make it easier to set up Sirrf-based projects accros multiple platforms.

See the change log for more information regarding the changes in Sirrf version 0.2.0.

This is not the end of Sirrf’s development, though. Sirrf’s development will continue and Sirrf will undoubtely become even better in the future. And you, as a Sirrf user, as a member of the Irrlicht community, can help us improve the framework. This can be done by contributing code to the project, but also by testing the framework. Either way, we hope that Sirrf will be of use.

Useful links
SourceForge.net page – http://sourceforge.net/projects/sirrf
Downloads – http://sourceforge.net/projects/sirrf/files/ | http://www.ohloh.net/p/sirrf/download?package=Sirrf

All in all, I think Ohloh is an interesting service. Certainly something worth a visit. And if you decide to visit Ohloh, don’t forget to visit my user page too.

Introduction to the Alliance

Games are a complicated beast. A Free Gaming Alliance could help free games during those steps that are crucial to making a successful game: organization, development and publication. And during all steps the goal of the alliance would be the same: to provide professional help to free games. Taking over projects should not be a first thought. Consultants of the alliance would work as external members of the development team. It is not completely unimaginable, though, that the alliance would take over a promising project with the consent of the development team. That way the alliance could allocate more people and money to the project. But again, this should not be the case with every project. Besides there would be also be cases funding would be possible without a project takeover.

Organization

In terms of organization the Free Gaming Alliance could help projects with finding a team. When it comes to the programming department, free games have few problems. However, when it comes to content creation there are more problems. If you have ever visited an amateur game development website you might have noticed that there are few artists (designers, modellers, composers, etc) in comparison to programmers. The solution would be quite simple, though. The alliance could host a website where artists and anybody else involved in game development could upload free content (models, music, pieces of code, etc). At the first place projects in development projects could get the content they need. And secondly anybody involved into free game development would have a place to show of their skills.
Furthermore the alliance could also advice projects on topics such as deadlines and anything else related to organization.

Development

With regard to development the Free Gaming Alliance would have a simple job. The general FOSS community has already produced various tools which can be used for game development: GIMP and Blender to name two. Also with regard to SDKs there are already many usable products. These SDKs range from low-level (OpenGL, OpenAL, etc) to high-level (Irrlicht, Ogre, CrystalSpace, Horde3d). But tools are only one (important) part of game development. Another part is the development of the game itself. This is something the project team will be responsible for them self, but the alliance could advice and actually commit content. Furthermore it is not completely unimaginable that the alliance would create their own tools, libraries and maybe even platforms for game development.

Publication

And last but not least: publication. There are already various hosts for FOSS: SourceForge.net, Google Code, Ohloh. However, these hosts are not game specific. It is quite possible that this scares potential gamers. The Free Gaming Alliance could fill in this gap. By doing this the alliance could also offer services to monetize on publication. These services could include marketing, merchandise, package publishing, etc. Of course this would not only benefit the alliance, but also the project (shared revenue).

Conclusion

Yet, the Free Gaming Alliance is still a dream. I would love to see a real-life implementation, but I realize that it would be quite an undertaking. Still, it is an interesting and I would not mind working for such alliance.

Useful links
SourceForge.net page – http://sourceforge.net/projects/sirrf
Downloads – http://sourceforge.net/project/showfiles.php?group_id=260711 | http://www.ohloh.net/p/sirrf/download?package=Sirrf

But what can Sirrf do for you? In it’s current state Sirrf offers game logic, graphics, scripting and sound control. Some noticeable features are:

• Data Store
  The Data Store allows you to store primitive value types such as integers, floats and doubles in a type-independent format. These variables can be accessed from anywhere within the framework, from both native and interpreted code, through the DataStore and DataStack classes.
• Entity Management
  In Sirrf entities are component-oriented. The idea behind Component Oriented Entities is to make entities data-driven. In order to do this the functionalities are split in various individual components. As a result an entity is in fact nothing more than a collection of components. So, what an entity represents, is defined by its components. Sirrf currently offers various components in the fields of graphics and sound. Furthermore Sirrf also provides an Entity Manager which should be seen as the central interface point to all entity related issues.
• Event Management
  Sirrf’s event management is build upon sigslot. This means that Sirrf follows an observer model where objects have to subscribe to an event if they want to react to that event. Currently observers can subscribe to game logic events, input events (passed from Irrlicht) and GUI events (again, passed from Irrlicht).
• Game Management
  The Game Manager performs generic game initialization and deinitialization. It also provides functions to access sub-systems of the framework, such as the Event Manager and the Entity Manager. It’s main function, though, is to control the flow of the game through game state management. This class provides various features to this end.
• Scripting
  Sirrf is almost completely accessible through AngelScript, a free and open source scripting language. AngelScript allows users to extend applications on run-time using scripts that follow a C/C++ like syntax. Furthermore it’s easy to extend Sirrf’s AngelScript bindings even further.

You might be wondering, though, if Sirrf is really something for you. It’s obvious that Sirrf is ideal for newcomers to Irrlicht and game development, but Sirrf should also be useful for experts. Especially now experts are more than welcome as Sirrf is still in beta status.

In the coming time focus will lie primarily at adding additional documentation. This will be an crucial step to make the framework more accessible to newcomers. And of course Sirrf will also be extended with new features.

Useful links
Development Hub – http://sourceforge.net/projects/sirrf
Downloads – https://sourceforge.net/project/showfiles.php?group_id=260711

The Sirrf Project

Project name

Sirrf – Simple Irrlicht Framework

Brief description

Sirrf, the Simple Irrlicht Framework, is an extensive, but open source and simple framework for rapid game development. Sirrf provides end-users a game skeleton which implements concepts such as states, component-based entities and a datastore. Newer hobbyist game developers will probably benefit most from the project, but hopefully Sirrf will also be useful for experienced developers.

Target aim

Long term

Making a game isn’t a simple task. The goal of the Sirrf project is to create an extensive, but simple framework to enable rapid game development. Furthermore, Sirrf is aimed for as broad of a target audience as possible. Sirrf hopes to accomplish this by maintaining a cross-platform nature and a lack of genre specialization. Additionally, the framework is not-for-profit and open source, licensed under the zlib/libpng license.

Short term

At the moment the main priority is to finish the core, which will form the base for future releases. The first release is expected after Irrlicht 1.6 and AngelScript 2.17.0 are released.

Compensation

Sirrf is open to donations, but this doesn’t guarantee regular financial compensation. So expect to work largely without financial compensation.

Technology

There are no requirements for developers to use specific tools; developers are free to choose their own tools. Please note that Sirrf currently uses the following languages and APIs:

Programming Language: C++
Scripting Language: AngelScript
Rendering: Irrlicht
Sound: SFML-Audio

Talent needed

C++ Programmers

Sirrf is looking for additional programmers. Moderate knowledge of C++ is required. Knowledge of other components, such as AngelScript and Irrlicht, is preferred. You’ll work with other programmers over the SVN of Sirrf. As programmer you’ll be working on multiple different areas of the code, but it’s possible to specialize on one part of the code. Additional programmers on the following topics would be much appreciated:

- Core Development (graphics, scripting, I/O)
- Physics

Windows and Mac OSX Maintainers

Sirrf is currently only supported on Linux; maintainers for Windows and Mac OSX are needed.

Team structure

Michael Bartsch

In the past I’ve worked on several projects. The smaller projects nearly always involved some implementation of Irrlicht. My bigger projects, however, are mostly unrelated to Irrlicht. My latest project was the Aia-project, a project with the goal to create a small artificial intelligent robot. And before that I worked on Entwined Worlds, a 2D Action-RPG, that has never been released. Furthermore, I’m one of the editors of .simplicity.

Contact Information

Contact me via SourceForge.

Additional Information

Links

Development Hub – http://apps.sourceforge.net/trac/sirrf/
SourceForge Project Page – http://sf.net/projects/sirrf/
Subversion Repository – http://sirrf.svn.sourceforge.net/viewvc/sirrf/