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Component based game engine design [closed]

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Are there any open source game engines?

Here Are Some Of The Best Open Source Game Engine. 1. Godot: Released with a mission to offer a fully integrated game development environment, Godot is considered to be one of the most powerful 2D and 3D cross-platform game engine. It is also an open source platform under the MIT License.

What game engine has no coding?

1. Gamemaker Studio. Gamemaker Studio is a game engine with a fairly active community base and already has its own store like Steam. This engine uses a drag and drop feature to make it easier for anyone who has never done coding to create a game.

What does it mean if a game engine is proprietary?

A proprietary game engine is a software framework designed for the creation and. development of video games. Currently, there are different games engines that allow. the development of games able to be applied in a wide range of browsers and platforms.

Is there a game engine that uses C++?

Many game engines use C++. The free game engines that use C++ are: CryEngine, Esenthel, G3D Innovation Engine, Godot, idTech, Irrlicht, Leadwerks, Limon Engine, Lumberyard, Lumix Engine, OGRE, Panda 3D, PhyreEngine, Source Engine (free if your game is free), Torque 3D, Toy Engine, Unigine, Unreal Engine, and Urho3D.


Update 2013-01-07: If you want to see a good mix of component-based game engine with the (in my opinion) superior approach of reactive programming take a look at the V-Play engine. It very well integrates QTs QML property binding functionality.

We did some research on CBSE in games at our university and I collected some material over the years:

CBSE in games literature:

  • Game Engine Architecture
  • Game Programming Gems 4: A System for Managin Game Entities Game
  • Game Programming Gems 5: Component Based Object Management
  • Game Programming Gems 5: A Generic Component Library
  • Game Programming Gems 6: Game Object Component System
  • Object-Oriented Game Development
  • Architektur des Kerns einer Game-Engine und Implementierung mit Java (german)

A very good and clean example of a component-based game-engine in C# is the Elephant game framework.

If you really want to know what components are read: Component-based Software Engineering! They define a component as:

A software component is a software element that conforms to a component model and can be independently deployed and composed without modification according to a composition standard.

A component model defines specific interaction and composition standards. A component model implementation is the dedicated set of executable software elements required to support the execution of components that conform to the model.

A software component infrastructure is a set of interacting software components designed to ensure that a software system or subsystem constructed using those components and interfaces will satisfy clearly defined performance specifications.

My opinions after 2 years of experience with CBSE in games thought are that object-oriented programming is simply a dead-end. Remember my warning as you watch your components become smaller and smaller, and more like functions packed in components with a lot of useless overhead. Use functional-reactive programming instead. Also take a look at my fresh blog post (which lead me to this question while writing it :)) about Why I switched from component-based game engine architecture to FRP.

CBSE in games papers:

  • Component Based Game Development – A Solution to Escalating Costs and Expanding Deadlines?
  • A Flexible And Expandable Architecture For Computer Games (404)
  • A Software Architecture for Games
  • A Generic Framework For Game Development (WebArchive)
  • Smart Composition Of Game Objects Using Dependency Injection

CBSE in games web-links (sorted by relevancy):

  • Component based objects Wiki (Empty wiki)
  • Evolve Your Hierachy
  • Game Object Structure: Inheritance vs. Aggregation
  • A Data-Driven Game Object System (PDF)
  • A Data-Driven Game Object System (PPT)
  • Component-based prototyping tool for flash
  • Theory and Practice of Game Object Component Architecture (404)
  • Entity Systems are the Future of MMOs
  • ogre3d.org forum: Component Based Objects
  • gamedev.net: Outboard component-based entity system architecture
  • gamedev.net: Entity System question
  • Brainfold entity-system blog (WebArchive)

There does seem to be a lack of information on the subject. I recently implemented this system, and I found a really good GDC Powerpoint that explained the details that are often left behind quite well. That document is here: Theory and Practice of Game Object Component Architecture

In addition to that Powerpoint, there are some good resources and various blogs. PurplePwny has a good discussion and links to some other resources. Ugly Baby Studios has a bit of a discussion around the idea of how components interact with each other. Good luck!


While not a complete tutorial on the subject of game engine design, I have found that this page has some good detail and examples on use of the component architecture for games.


It is open-source, and available at http://codeplex.com/elephant

Some one’s made a working example of the gpg6-code, you can find it here: http://www.unseen-academy.de/componentSystem.html

or here: http://www.mcshaffry.com/GameCode/thread.php?threadid=732

regards


I am currently researching this exact topic in the many (MANY) threads at GameDev.net and found the following two solutions to be good candidates on what I will develop for my game:

  • Critique my component-based entity system
  • Outboard component-based entity system architecture -> Lord_Evil's proposal

I researched and implemented this last semester for a game development course. Hopefully this sample code can point you in the right direction of how you might approach this.

class Entity {
public:
    Entity(const unsigned int id, const std::string& enttype);
    ~Entity();

    //Component Interface
    const Component* GetComponent(const std::string& family) const;
    void SetComponent(Component* newComp);
    void RemoveComponent(const std::string& family);
    void ClearComponents();

    //Property Interface
    bool HasProperty(const std::string& propName) const;
    template<class T> T& GetPropertyDataPtr(const std::string& propName);
    template<class T> const T& GetPropertyDataPtr(const std::string& propName) const;

    //Entity Interface
    const unsigned int GetID() const;
    void Update(float dt);

private:
    void RemoveProperty(const std::string& propName);
    void ClearProperties();
    template<class T> void AddProperty(const std::string& propName);
    template<class T> Property<T>* GetProperty(const std::string& propName);
    template<class T> const Property<T>* GetProperty(const std::string& propName) const;

    unsigned int m_Id;
    std::map<const string, IProperty*> m_Properties;
    std::map<const string, Component*> m_Components;
};

Components specify behavior and operate on properties. Properties are shared between all components by a reference and get updates for free. This means no large overhead for message passing. If there's any questions I'll try to answer as best I can.