• Notes
• Functions
• User Contributed Notes

• engine.inc (Provides base engine natives.)
• engine_stocks.inc (Provides base engine functions to make certain tasks easier.)
• engine_const.inc (Contains constants related to Engine's native functions.)

• Speech Constants
• Camera Constants
• Message Constants

• Entity Integer Keys
• Entity Float Keys
• Entity Vector Keys
• Entity Edict Keys
• Entity String Keys
• Entity Byte Keys

• Button Constants
• Movement Constants
• Solid Constants
• Contents Constants
• Damage Constants

#define SPEAK_NORMAL		0
#define SPEAK_MUTED		1
#define SPEAK_ALL		2
#define SPEAK_LISTENALL		4

#define CAMERA_NONE		0
#define CAMERA_3RDPERSON	1
#define CAMERA_UPLEFT		2
#define CAMERA_TOPDOWN		3

#define BLOCK_NOT		0
#define BLOCK_ONCE		1
#define BLOCK_SET		2

enum {
	ARG_BYTE = 1,			/* int */
	ARG_CHAR,			/* int */
	ARG_SHORT,			/* int */
	ARG_LONG,			/* int */
	ARG_ANGLE,			/* float */
	ARG_COORD,			/* float */
	ARG_STRING,			/* string */
	ARG_ENTITY,			/* int */
}

enum {
	EV_INT_gamestate = 0,
	EV_INT_oldbuttons,
	EV_INT_groupinfo,
	EV_INT_iuser1,
	EV_INT_iuser2,
	EV_INT_iuser3,
	EV_INT_iuser4,
	EV_INT_weaponanim,
	EV_INT_pushmsec,
	EV_INT_bInDuck,
	EV_INT_flTimeStepSound,
	EV_INT_flSwimTime,
	EV_INT_flDuckTime,
	EV_INT_iStepLeft,
	EV_INT_movetype,
	EV_INT_solid,
	EV_INT_skin,
	EV_INT_body,
	EV_INT_effects,
	EV_INT_light_level,
	EV_INT_sequence,
	EV_INT_gaitsequence,
	EV_INT_modelindex,
	EV_INT_playerclass,
	EV_INT_waterlevel,
	EV_INT_watertype,
	EV_INT_spawnflags,
	EV_INT_flags,
	EV_INT_colormap,
	EV_INT_team,
	EV_INT_fixangle,
	EV_INT_weapons,
	EV_INT_rendermode,
	EV_INT_renderfx,
	EV_INT_button,
	EV_INT_impulse,
	EV_INT_deadflag,
}

enum {
	EV_FL_impacttime = 0,
	EV_FL_starttime,
	EV_FL_idealpitch,
	EV_FL_pitch_speed,
	EV_FL_ideal_yaw,
	EV_FL_yaw_speed,
	EV_FL_ltime,
	EV_FL_nextthink,
	EV_FL_gravity,
	EV_FL_friction,
	EV_FL_frame,
	EV_FL_animtime,
	EV_FL_framerate,
	EV_FL_health,
	EV_FL_frags,
	EV_FL_takedamage,
	EV_FL_max_health,
	EV_FL_teleport_time,
	EV_FL_armortype,
	EV_FL_armorvalue,
	EV_FL_dmg_take,
	EV_FL_dmg_save,
	EV_FL_dmg,
	EV_FL_dmgtime,
	EV_FL_speed,
	EV_FL_air_finished,
	EV_FL_pain_finished,
	EV_FL_radsuit_finished,
	EV_FL_scale,
	EV_FL_renderamt,
	EV_FL_maxspeed,
	EV_FL_fov,
	EV_FL_flFallVelocity,
	EV_FL_fuser1,
	EV_FL_fuser2,
	EV_FL_fuser3,
	EV_FL_fuser4,
}

enum {
	EV_VEC_origin = 0,
	EV_VEC_oldorigin,
	EV_VEC_velocity,
	EV_VEC_basevelocity,
	EV_VEC_clbasevelocity,
	EV_VEC_movedir,
	EV_VEC_angles,
	EV_VEC_avelocity,
	EV_VEC_punchangle,
	EV_VEC_v_angle,
	EV_VEC_endpos,
	EV_VEC_startpos,
	EV_VEC_absmin,
	EV_VEC_absmax,
	EV_VEC_mins,
	EV_VEC_maxs,
	EV_VEC_size,
	EV_VEC_rendercolor,
	EV_VEC_view_ofs,
	EV_VEC_vuser1,
	EV_VEC_vuser2,
	EV_VEC_vuser3,
	EV_VEC_vuser4,
}

enum {
	EV_ENT_chain = 0,
	EV_ENT_dmg_inflictor,
	EV_ENT_enemy,
	EV_ENT_aiment,
	EV_ENT_owner,
	EV_ENT_groundentity,
	EV_ENT_pContainingEntity,
	EV_ENT_euser1,
	EV_ENT_euser2,
	EV_ENT_euser3,
	EV_ENT_euser4,
}

enum {
	EV_SZ_classname = 0,
	EV_SZ_globalname,
	EV_SZ_model,
	EV_SZ_target,
	EV_SZ_targetname,
	EV_SZ_netname,
	EV_SZ_message,
	EV_SZ_noise,
	EV_SZ_noise1,
	EV_SZ_noise2,
	EV_SZ_noise3,
	EV_SZ_viewmodel,
	EV_SZ_weaponmodel,
}

enum {
	EV_BYTE_controller1 = 0,
	EV_BYTE_controller2,
	EV_BYTE_controller3,
	EV_BYTE_controller4,
	EV_BYTE_blending1,
	EV_BYTE_blending2,
}

#define IN_ATTACK		(1<<0)
#define IN_JUMP			(1<<1)
#define IN_DUCK			(1<<2)
#define IN_FORWARD		(1<<3)
#define IN_BACK			(1<<4)
#define IN_USE			(1<<5)
#define IN_CANCEL		(1<<6)
#define IN_LEFT			(1<<7)
#define IN_RIGHT		(1<<8)
#define IN_MOVELEFT		(1<<9)
#define IN_MOVERIGHT		(1<<10)
#define IN_ATTACK2		(1<<11)
#define IN_RUN			(1<<12)
#define IN_RELOAD		(1<<13)
#define IN_ALT1			(1<<14)
#define IN_SCORE		(1<<15)

#define	FL_FLY			(1<<0)		/* Changes the SV_Movestep() behavior to not need to be on ground */
#define	FL_SWIM			(1<<1)		/* Changes the SV_Movestep() behavior to not need to be on ground (but stay in water) */
#define	FL_CONVEYOR		(1<<2)
#define	FL_CLIENT		(1<<3)
#define	FL_INWATER		(1<<4)
#define	FL_MONSTER		(1<<5)
#define	FL_GODMODE		(1<<6)
#define	FL_NOTARGET		(1<<7)
#define	FL_SKIPLOCALHOST	(1<<8)		/* Don't send entity to local host, it's predicting this entity itself */
#define	FL_ONGROUND		(1<<9)		/* At rest / on the ground */
#define	FL_PARTIALGROUND	(1<<10)		/* not all corners are valid */
#define	FL_WATERJUMP		(1<<11)		/* player jumping out of water */
#define FL_FROZEN		(1<<12) 	/* Player is frozen for 3rd person camera */
#define FL_FAKECLIENT		(1<<13)		/* JAC: fake client, simulated server side; don't send network messages to them */
#define FL_DUCKING		(1<<14)		/* Player flag -- Player is fully crouched */
#define FL_FLOAT		(1<<15)		/* Apply floating force to this entity when in water */
#define FL_GRAPHED		(1<<16)		/* worldgraph has this ent listed as something that blocks a connection */
#define FL_IMMUNE_WATER		(1<<17)
#define	FL_IMMUNE_SLIME		(1<<18)
#define FL_IMMUNE_LAVA		(1<<19)
#define FL_PROXY		(1<<20)		/* This is a spectator proxy */
#define FL_ALWAYSTHINK		(1<<21)		/* Brush model flag -- call think every frame regardless of nextthink - ltime (for constantly changing velocity/path) */
#define FL_BASEVELOCITY		(1<<22)		/* Base velocity has been applied this frame (used to convert base velocity into momentum) */
#define FL_MONSTERCLIP		(1<<23)		/* Only collide in with monsters who have FL_MONSTERCLIP set */
#define FL_ONTRAIN		(1<<24)		/* Player is _controlling_ a train, so movement commands should be ignored on client during prediction. */
#define FL_WORLDBRUSH		(1<<25)		/* Not moveable/removeable brush entity (really part of the world, but represented as an entity for transparency or something) */
#define FL_SPECTATOR		(1<<26) 	/* This client is a spectator, don't run touch functions, etc. */
#define FL_CUSTOMENTITY		(1<<29)		/* This is a custom entity */
#define FL_KILLME		(1<<30)		/* This entity is marked for death -- This allows the engine to kill ents at the appropriate time */
#define FL_DORMANT		(1<<31)		/* Entity is dormant, no updates to client */
#define	MOVETYPE_NONE		0		/* never moves */
#define MOVETYPE_ANGLENOCLIP	1
#define MOVETYPE_ANGLECLIP	2
#define	MOVETYPE_WALK		3		/* Player only - moving on the ground */
#define	MOVETYPE_STEP		4		/* gravity, special edge handling -- monsters use this */
#define	MOVETYPE_FLY		5		/* No gravity, but still collides with stuff */
#define	MOVETYPE_TOSS		6		/* gravity/collisions */
#define	MOVETYPE_PUSH		7		/* no clip to world, push and crush */
#define	MOVETYPE_NOCLIP		8		/* No gravity, no collisions, still do velocity/avelocity */
#define	MOVETYPE_FLYMISSILE	9		/* extra size to monsters */
#define	MOVETYPE_BOUNCE		10		/* Just like Toss, but reflect velocity when contacting surfaces */
#define MOVETYPE_BOUNCEMISSILE	11		/* bounce w/o gravity */
#define MOVETYPE_FOLLOW		12		/* track movement of aiment */
#define	MOVETYPE_PUSHSTEP	13		/* BSP model that needs physics/world collisions (uses nearest hull for world collision) */

#define	SOLID_NOT		0		/* no interaction with other objects */
#define	SOLID_TRIGGER		1		/* touch on edge, but not blocking */
#define	SOLID_BBOX		2		/* touch on edge, block */
#define	SOLID_SLIDEBOX		3		/* touch on edge, but not an onground */
#define	SOLID_BSP		4		/* bsp clip, touch on edge, block */

#define	CONTENTS_EMPTY		-1
#define	CONTENTS_SOLID		-2
#define	CONTENTS_WATER		-3
#define	CONTENTS_SLIME		-4
#define	CONTENTS_LAVA		-5
#define	CONTENTS_SKY		-6
#define	CONTENTS_ORIGIN		-7		/* removed at csg time */
#define	CONTENTS_CLIP		-8		/* changed to contents_solid */
#define	CONTENTS_CURRENT_0	-9
#define	CONTENTS_CURRENT_90	-10
#define	CONTENTS_CURRENT_180	-11
#define	CONTENTS_CURRENT_270	-12
#define	CONTENTS_CURRENT_UP	-13
#define	CONTENTS_CURRENT_DOWN	-14
#define CONTENTS_TRANSLUCENT	-15
#define	CONTENTS_LADDER		-16

#define DMG_GENERIC		0		/* generic damage was done */
#define DMG_CRUSH		(1<<0)		/* crushed by falling or moving object */
#define DMG_BULLET		(1<<1)		/* shot */
#define DMG_SLASH		(1<<2)		/* cut, clawed, stabbed */
#define DMG_BURN		(1<<3)		/* heat burned */
#define DMG_FREEZE		(1<<4)		/* frozen */
#define DMG_FALL		(1<<5)		/* fell too far */
#define DMG_BLAST		(1<<6)		/* explosive blast damage */
#define DMG_CLUB		(1<<7)		/* crowbar, punch, headbutt */
#define DMG_SHOCK		(1<<8)		/* electric shock */
#define DMG_SONIC		(1<<9)		/* sound pulse shockwave */
#define DMG_ENERGYBEAM		(1<<10)		/* laser or other high energy beam */
#define DMG_NEVERGIB		(1<<12)		/* with this bit OR'd in, no damage type will be able to gib victims upon death */
#define DMG_ALWAYSGIB		(1<<13)		/* with this bit OR'd in, any damage type can be made to gib victims upon death */
#define DMG_DROWN		(1<<14)		/* Drowning */
/* time-based damage */
#define DMG_TIMEBASED		(~(0x3fff))	/* mask for time-based damage */
/* TF Additions */
#define DMG_PARALYZE		(1<<15)		/* slows affected creature down */
#define DMG_NERVEGAS		(1<<16)		/* nerve toxins, very bad */
#define DMG_POISON		(1<<17)		/* blood poisioning */
#define DMG_RADIATION		(1<<18)		/* radiation exposure */
#define DMG_DROWNRECOVER	(1<<19)		/* drowning recovery */
#define DMG_ACID		(1<<20)		/* toxic chemicals or acid burns */
#define DMG_SLOWBURN		(1<<21)		/* in an oven */
#define DMG_SLOWFREEZE		(1<<22)		/* in a subzero freezer */
#define DMG_MORTAR		(1<<23)		/* Hit by air raid (done to distinguish grenade from mortar) */