A start to explaining Quake 3

Probably not quite right, but it's a start. I'm forced to make some guesses about the structure, due to me not actually having the game, and not being able to test my suppositions.

(g) means a file is in the game folder, (c) means the client folder, (u) means the ui folder

The main data structure for entities in q3 is shown below. this is stored in q_shared.h in the game directory (it's linked to directly by most of the other code (the *_local.h files link to it)

I'm pulling together definitions for each of the fields in it. each field that is a link, links to the definitions I've been able to find. Comments I've added are in blue.

The entity state structure (sent from server to client)
typedef struct entityState_s {

int number; // entity index int eType; // entityType_t int eFlags; // This would appear to be refering to this list of flags trajectory_t pos; // for calculating position trajectory_t apos; // for calculating angles int time; // not sure what these two are for int time2; vec3_t origin; // a 3 dimensional array of floats (Note) vec3_t origin2; // these 2 are probably used for the actual location of the entity, and where it was a frame ago vec3_t angles; //These 2 will probably be for current angles, and angles a frame ago vec3_t angles2; int otherEntityNum; // shotgun sources, etc int otherEntityNum2; // not a clue here yet int groundEntityNum; // -1 = in air int constantLight; // r + (g<<8) + (b<<16) + (intensity<<24) int loopSound; // constantly loop this sound int modelindex; int modelindex2; int clientNum; // 0 to (MAX_CLIENTS - 1), for players and corpses int frame; int solid; // for client side prediction, trap_linkentity sets this properly int event; // impulse events -- muzzle flashes, footsteps, etc int eventParm; // for players int powerups; // bit flags int weapon; // determines weapon and flash model, etc int legsAnim; // mask off ANIM_TOGGLEBIT int torsoAnim; // mask off ANIM_TOGGLEBIT

} entityState_t;

This is the list of types that an entity can be. when I find out the effects these have on the game, I'll update it (in bg_public.h (in game))

typedef enum {
	ET_GENERAL,
	ET_PLAYER,
	ET_ITEM,
	ET_MISSILE,
	ET_MOVER,
	ET_BEAM,
	ET_PORTAL,
	ET_SPEAKER,
	ET_PUSH_TRIGGER,
	ET_TELEPORT_TRIGGER,
	ET_INVISIBLE,
	ET_GRAPPLE,				// grapple hooked on wall

	ET_EVENTS				// any of the EV_* events can be added freestanding
							// by setting eType to ET_EVENTS + eventNum
							// this avoids having to set eFlags and eventNum
} entityType_t;

Also in bg_public.h (g) All I can find for the moment

// entityState_t->eFlags
#define	EF_DEAD				0x00000001		// don't draw a foe marker over players with EF_DEAD
#define	EF_TELEPORT_BIT		0x00000004		// toggled every time the origin abruptly changes
#define	EF_AWARD_EXCELLENT	0x00000008		// draw an excellent sprite
#define	EF_BOUNCE			0x00000010		// for missiles
#define	EF_BOUNCE_HALF		0x00000020		// for missiles
#define	EF_AWARD_GAUNTLET	0x00000040		// draw a gauntlet sprite
#define	EF_NODRAW			0x00000080		// may have an event, but no model (unspawned items)
#define	EF_FIRING			0x00000100		// for lightning gun
#define	EF_MOVER_STOP		0x00000400		// will push otherwise
#define	EF_TALK				0x00001000		// draw a talk balloon
#define	EF_CONNECTION		0x00002000		// draw a connection trouble sprite
#define	EF_VOTED			0x00004000		// already cast a vote
#define	EF_AWARD_IMPRESSIVE	0x00008000		// draw an impressive sprite

From q_shared.h(g).

typedef struct {
	trType_t	trType;
	int		trTime;
	int		trDuration;			// if non 0, trTime + trDuration = stop time
	vec3_t	trBase;
	vec3_t	trDelta;			// velocity, etc
} trajectory_t;

I checked to see if this has changed. it has, kinda. heres it's defintion, along with some others

typedef float vec_t;
typedef vec_t vec2_t[2];
typedef vec_t vec3_t[3];
typedef vec_t vec4_t[4];
typedef vec_t vec5_t[5];

I don't know why they've done it this way yet, but I'm planning to find out

The client structure (I'm working on the defintions)

struct gclient_s {
	// ps MUST be the first element, because the server expects it
	playerState_t	ps;				// communicated by server to clients

	// the rest of the structure is private to game
	clientPersistant_t	pers;
	clientSession_t		sess;

	qboolean	readyToExit;		// wishes to leave the intermission

	qboolean	noclip;

	int			lastCmdTime;		// level.time of last usercmd_t, for EF_CONNECTION
									// we can't just use pers.lastCommand.time, because
									// of the g_sycronousclients case
	int			buttons;
	int			oldbuttons;
	int			latched_buttons;

	// sum up damage over an entire frame, so
	// shotgun blasts give a single big kick
	int			damage_armor;		// damage absorbed by armor
	int			damage_blood;		// damage taken out of health
	int			damage_knockback;	// impact damage
	vec3_t		damage_from;		// origin for vector calculation
	qboolean	damage_fromWorld;	// if true, don't use the damage_from vector

	int			accurateCount;		// for "impressive" reward sound

	//
	int			lasthurt_client;	// last client that damaged this client
	int			lasthurt_mod;		// type of damage the client did

	// timers
	int			respawnTime;		// can respawn when time > this, force after g_forcerespwan
	int			inactivityTime;		// kick players when time > this
	qboolean	inactivityWarning;	// qtrue if the five seoond warning has been given
	int			rewardTime;			// clear the EF_AWARD_IMPRESSIVE, etc when time > this

	int			airOutTime;

	int			lastKillTime;		// for multiple kill rewards

	qboolean	fireHeld;			// used for hook
	gentity_t	*hook;				// grapple hook if out

	// timeResidual is used to handle events that happen every second
	// like health / armor countdowns and regeneration
	int			timeResidual;
};

Entity Flags

// gentity->flags
#define	FL_GODMODE				0x00000010
#define	FL_NOTARGET				0x00000020
#define	FL_TEAMSLAVE			0x00000400	// not the first on the team
#define FL_NO_KNOCKBACK			0x00000800
#define FL_DROPPED_ITEM			0x00001000
#define FL_NO_BOTS				0x00002000	// spawn point not for bot use
#define FL_NO_HUMANS			0x00004000	// spawn point just for bots