BF2 Internals

The BF2 engine has been written in C++ and also make heavy use of STL.

Reference Counting

A lot of the internal components of the game use intrusive reference counting through inheritance. The base class would look something like this:

class RefCounted {
public:
    RefCounted() : m_refCount(1) {}
    virtual ~RefCounted() {}

    virtual int addRef() {
        return ++m_refCount;
    }
    
    virtual int getRefCount() const {
        return m_refCount;
    }

    // Unsure if there actually is a base implementation of this method,
    // this is almost always points to a unique function in the vtable but follows this pattern.
    virtual int release() {
        if (--m_refCount == 0) {
            delete (RefCounted*)this;
        }
        return m_refCount;
    }
private:
    int m_refCount;
};

Do note that this class is not thread-safe, as in the actual implementation.

ClassManager

The program contains a single ClassManager instance which is used to dynamically access different subsystems within the game. These subsystems are registered via a string identifier(class name), an instance pointer, the class id and another unknown integer, they can then later be accessed using the class name. The following classes are registered in BF2.exe:

GameServerSettings

HudInformationLayer

DistributedLightRenderer

LocalProfileManager

ProfileManager

RankManager

ClanManager

NewsManager

AutoPatch

Persistence

MenuTeamManager

GlobalSettings

VideoSettings

AudioSettings

ControlSettings

GeneralSettings

HapticSettings

ServerBrowserManager

SwiffHost

DemoLibrary

ServerLogoManager

ModInfo

The rendering module(RendDX9.dll) also registers the following classes:

SwiffRenderer

Terrain

LightManager

GeometryTemplateManager

StaticMeshRenderer

SkinnedMeshRenderer

ParticleSystemManager

HemiMapManager

DecalManager

DecalShadowManager

RoadCompiledRenderer

RoadEditableRenderer

NametagManager

SkyDome

UndergrowthSystem

LightingManager

WeatherManager

RainManager

RenderView

EnvMapManager

Common

GameEvent

The game has multiple event systems, game events are events that occur in-game and are related to gameplay. The (incomplete) class below is the base class used by all events, events often have additional data.

class GameEvent : public RefCounted {
public:
    GameEvent() : field_8(-1) {}
    
    // multiple virtual functions here
private:
    int field_8;
};

List of Game events:

ChallengeEvent

ChallengeResponseEvent

ConnectionTypeEvent

DataBlockEvent

CreatePlayerEvent

CreateObjectEvent

CreateKitEvent

DestroyObjectEvent

DestroyPlayerEvent

EnterVehicleEvent

ExitVehicleEvent

PostRemoteEvent

ChangePlayerNameEvent

HandlePickupEvent

HandleDropEvent

StringBlockEvent

JoinSquadEvent

LeaveSquadEvent

CommanderEvent

RadioMessageEvent

KilledByEvent

ChangeSquadNameEvent

SetPrivateSquadEvent

IssueSquadOrderEvent

InviteEvent

RankEvent

KickBanEvent

SetAcceptOrderEvent

SetSquadLeaderEvent

SpottedEvent

ArtilleryEvent

StickyProjectileEvent

AmbientEffectAreaEvent

VoipOnOffEvent

CommanderCamEvent

SupplyDropEvent

VoidPlayerMuteEvent

VoteEvent

TargetDirectionEvent

BeginRoundEvent

EndOfRoundEvent

PythonCommandEvent

RequestEvent

VoipSessionEvent

ToggleFreeCameraEvent

MedalEvent

UnlockEvent

MissileInitEvent

UAVEvent

ContentCheckEvent

DropVehicleEvent

CreateSpawnGroupEvent

RemoveSpawnGroupEvent

UpdateTriggerEvent

GrapplingHookContainerCreateEvent

GrapplingHookContainerUpdateEvent

GrapplingHookContainerDetachEvent

GrapplingHookCreateEvent

GrapplingHookUpdateEvent

PlayerTearGassedEvent

SetNightVisionEvent

VerifyPlayerTeamEvent

FixPlayerTeamEvent