edict_t
edict_t ("entity dictionary") is an interface struct that allows entities to cross the client/server divide: with one attached, an entity has the same index at both ends. The edict also manages the state of the entity's DataTable and provides a common representation across all DLLs. It cannot be used on the client.
Note:An edict is not reliable between frames, as it can be freed from one entity and and reallocated to another at any time. Use CHandle for long-term storage.
Warning:Never modify edict_t or CBaseEdict. If the memory footprint of either changes, engine DLLs will start accessing invalid addresses.Limitations
Warning:In most games, 
Source can have up to 2048 edicts allocated at any one time. Going over will cause the engine to crash with an error message.
Note:This limit is raised to 4096 in 
Portal 2 and 8192 in 
Garry's Mod and 
Portal 2: Community Edition.
Counter-Strike: Global Offensive and 
Team Fortress 2 have the default limit of 2048.
Tip:
GoldSrc has a maximum of 1200 edicts by default (900 prior to 25th-anniversary update), but this can be raised to 2048 in a mod by editing its liblist.gam to include the line edicts "2048".
Confirm:What about 
Sven Co-op?Avoiding
Server only entities
(only in )
Edicts are assigned by CBaseEntity::PostConstructor(). If your entity won't ever need to be transmitted to the client, construct it like so:
CMyEntity() : CBaseEntity(true) { /* your constructor code */ }
Tip:CServerOnlyEntity already does this. CLogicalEntity inherits, and as such none of Valve's logic entities or VPhysics constraints have edicts.Edict-less entities count toward non-networked entity limit, which is also 2048.
Entities compiled into the map which are not recognized by the game code do not count towards any entity limit in-game as they are simply not spawned.
Client-only entities
Todo: If the game is not singleplayer, and the entity is non-solid and is not part of
s_PreserveEnts, it can be removed server-side. See env_sprite_clientside source code in Alien Swarm for example implementation in Source. In GoldSrc, use MAKE_STATIC.Getting
edict_t* CBaseEntity::edict()- Simple accessor. Returns null if there is no edict.
edict_t* INDEXENT( int iEdictNum )int ENTINDEX( edict_t* pEdict )- Converts between an entity index and its attached edict.
int GetEntityCount()- Returns the current number of assigned edicts (not entities).
Setting
void CBaseEntity::NetworkProp()->AttachEdict(edict_t* pRequiredEdict);- Assigns an edict via the entity's
CServerNetworkPropertyobject. Pass NULL unless a specific edict is required. void CBaseEntity::NetworkProp()->DetachEdict()- Detaches the entity's assigned edict. It will go back into the edict pool for re-use.
Notable members
CBaseEntity* GetUnknown()->GetBaseEntity()- Pointer to the entity's local representation.
char* GetClassName()- The classname of the assigned entity.
bool IsFree()- Whether there is currently an entity assigned to this edict.
float freetime- The server timestamp at which the edict was last freed. Can be used to avoid reallocating the edict immediately.
bool HasStateChanged()- Whether anything in the DataTable needs transmission.
void StateChanged()- Tell the edict of a change to the entity's DataTable that needs transmission.
IServerEntity* GetIServerEntity()IServerNetworkable* GetNetworkable()ICollideable* GetCollideable()- Accessors to various interfaces.
