g_items.c

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		ent->r.svFlags |= SVF_NOCLIENT;
		ent->s.eFlags |= EF_NODRAW;
		ent->r.contents = 0;
		ent->unlinkAfterEvent = qtrue;
		return;
	}

	// non zero wait overrides respawn time
	if ( ent->wait ) {
		respawn = ent->wait;
	}

	// random can be used to vary the respawn time
	if ( ent->random ) {
		respawn += crandom() * ent->random;
		if ( respawn < 1 ) {
			respawn = 1;
		}
	}

	// dropped items will not respawn
	if ( ent->flags & FL_DROPPED_ITEM ) {
		ent->freeAfterEvent = qtrue;
	}

	// picked up items still stay around, they just don't
	// draw anything.  This allows respawnable items
	// to be placed on movers.
	ent->r.svFlags |= SVF_NOCLIENT;
	ent->s.eFlags |= EF_NODRAW;
	ent->r.contents = 0;

	// ZOID
	// A negative respawn times means to never respawn this item (but don't 
	// delete it).  This is used by items that are respawned by third party 
	// events such as ctf flags
	if ( respawn <= 0 ) {
		ent->nextthink = 0;
		ent->think = 0;
	} else {
		ent->nextthink = level.time + respawn * 1000;
		ent->think = RespawnItem;
	}
	trap_LinkEntity( ent );
}


//======================================================================

/*
================
LaunchItem

Spawns an item and tosses it forward
================
*/
gentity_t *LaunchItem( gitem_t *item, vec3_t origin, vec3_t velocity ) {
	gentity_t	*dropped;

	dropped = G_Spawn();

	dropped->s.eType = ET_ITEM;
	dropped->s.modelindex = item - bg_itemlist;	// store item number in modelindex
	dropped->s.modelindex2 = 1; // This is non-zero is it's a dropped item

	dropped->classname = item->classname;
	dropped->item = item;
	VectorSet (dropped->r.mins, -ITEM_RADIUS, -ITEM_RADIUS, -ITEM_RADIUS);
	VectorSet (dropped->r.maxs, ITEM_RADIUS, ITEM_RADIUS, ITEM_RADIUS);
	dropped->r.contents = CONTENTS_TRIGGER;

	dropped->touch = Touch_Item;

	G_SetOrigin( dropped, origin );
	dropped->s.pos.trType = TR_GRAVITY;
	dropped->s.pos.trTime = level.time;
	VectorCopy( velocity, dropped->s.pos.trDelta );

	dropped->s.eFlags |= EF_BOUNCE_HALF;
#ifdef MISSIONPACK
	if ((g_gametype.integer == GT_CTF || g_gametype.integer == GT_1FCTF)			&& item->giType == IT_TEAM) { // Special case for CTF flags
#else
	if (g_gametype.integer == GT_CTF && item->giType == IT_TEAM) { // Special case for CTF flags
#endif
		dropped->think = Team_DroppedFlagThink;
		dropped->nextthink = level.time + 30000;
		Team_CheckDroppedItem( dropped );
	} else { // auto-remove after 30 seconds
		dropped->think = G_FreeEntity;
		dropped->nextthink = level.time + 30000;
	}

	dropped->flags = FL_DROPPED_ITEM;

	trap_LinkEntity (dropped);

	return dropped;
}

/*
================
Drop_Item

Spawns an item and tosses it forward
================
*/
gentity_t *Drop_Item( gentity_t *ent, gitem_t *item, float angle ) {
	vec3_t	velocity;
	vec3_t	angles;

	VectorCopy( ent->s.apos.trBase, angles );
	angles[YAW] += angle;
	angles[PITCH] = 0;	// always forward

	AngleVectors( angles, velocity, NULL, NULL );
	VectorScale( velocity, 150, velocity );
	velocity[2] += 200 + crandom() * 50;
	
	return LaunchItem( item, ent->s.pos.trBase, velocity );
}


/*
================
Use_Item

Respawn the item
================
*/
void Use_Item( gentity_t *ent, gentity_t *other, gentity_t *activator ) {
	RespawnItem( ent );
}

//======================================================================

/*
================
FinishSpawningItem

Traces down to find where an item should rest, instead of letting them
free fall from their spawn points
================
*/
void FinishSpawningItem( gentity_t *ent ) {
	trace_t		tr;
	vec3_t		dest;

	VectorSet( ent->r.mins, -ITEM_RADIUS, -ITEM_RADIUS, -ITEM_RADIUS );
	VectorSet( ent->r.maxs, ITEM_RADIUS, ITEM_RADIUS, ITEM_RADIUS );

	ent->s.eType = ET_ITEM;
	ent->s.modelindex = ent->item - bg_itemlist;		// store item number in modelindex
	ent->s.modelindex2 = 0; // zero indicates this isn't a dropped item

	ent->r.contents = CONTENTS_TRIGGER;
	ent->touch = Touch_Item;
	// useing an item causes it to respawn
	ent->use = Use_Item;

	if ( ent->spawnflags & 1 ) {
		// suspended
		G_SetOrigin( ent, ent->s.origin );
	} else {
		// drop to floor
		VectorSet( dest, ent->s.origin[0], ent->s.origin[1], ent->s.origin[2] - 4096 );
		trap_Trace( &tr, ent->s.origin, ent->r.mins, ent->r.maxs, dest, ent->s.number, MASK_SOLID );
		if ( tr.startsolid ) {
			G_Printf ("FinishSpawningItem: %s startsolid at %s\n", ent->classname, vtos(ent->s.origin));
			G_FreeEntity( ent );
			return;
		}

		// allow to ride movers
		ent->s.groundEntityNum = tr.entityNum;

		G_SetOrigin( ent, tr.endpos );
	}

	// team slaves and targeted items aren't present at start
	if ( ( ent->flags & FL_TEAMSLAVE ) || ent->targetname ) {
		ent->s.eFlags |= EF_NODRAW;
		ent->r.contents = 0;
		return;
	}

	// powerups don't spawn in for a while
	if ( ent->item->giType == IT_POWERUP ) {
		float	respawn;

		respawn = 45 + crandom() * 15;
		ent->s.eFlags |= EF_NODRAW;
		ent->r.contents = 0;
		ent->nextthink = level.time + respawn * 1000;
		ent->think = RespawnItem;
		return;
	}


	trap_LinkEntity (ent);
}


qboolean	itemRegistered[MAX_ITEMS];

/*
==================
G_CheckTeamItems
==================
*/
void G_CheckTeamItems( void ) {

	// Set up team stuff
	Team_InitGame();

	if( g_gametype.integer == GT_CTF ) {
		gitem_t	*item;

		// check for the two flags
		item = BG_FindItem( "Red Flag" );
		if ( !item || !itemRegistered[ item - bg_itemlist ] ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_CTF_redflag in map" );
		}
		item = BG_FindItem( "Blue Flag" );
		if ( !item || !itemRegistered[ item - bg_itemlist ] ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_CTF_blueflag in map" );
		}
	}
#ifdef MISSIONPACK
	if( g_gametype.integer == GT_1FCTF ) {
		gitem_t	*item;

		// check for all three flags
		item = BG_FindItem( "Red Flag" );
		if ( !item || !itemRegistered[ item - bg_itemlist ] ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_CTF_redflag in map" );
		}
		item = BG_FindItem( "Blue Flag" );
		if ( !item || !itemRegistered[ item - bg_itemlist ] ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_CTF_blueflag in map" );
		}
		item = BG_FindItem( "Neutral Flag" );
		if ( !item || !itemRegistered[ item - bg_itemlist ] ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_CTF_neutralflag in map" );
		}
	}

	if( g_gametype.integer == GT_OBELISK ) {
		gentity_t	*ent;

		// check for the two obelisks
		ent = NULL;
		ent = G_Find( ent, FOFS(classname), "team_redobelisk" );
		if( !ent ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_redobelisk in map" );
		}

		ent = NULL;
		ent = G_Find( ent, FOFS(classname), "team_blueobelisk" );
		if( !ent ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_blueobelisk in map" );
		}
	}

	if( g_gametype.integer == GT_HARVESTER ) {
		gentity_t	*ent;

		// check for all three obelisks
		ent = NULL;
		ent = G_Find( ent, FOFS(classname), "team_redobelisk" );
		if( !ent ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_redobelisk in map" );
		}

		ent = NULL;
		ent = G_Find( ent, FOFS(classname), "team_blueobelisk" );
		if( !ent ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_blueobelisk in map" );
		}

		ent = NULL;
		ent = G_Find( ent, FOFS(classname), "team_neutralobelisk" );
		if( !ent ) {
			G_Printf( S_COLOR_YELLOW "WARNING: No team_neutralobelisk in map" );
		}
	}
#endif
}

/*
==============
ClearRegisteredItems
==============
*/
void ClearRegisteredItems( void ) {
	memset( itemRegistered, 0, sizeof( itemRegistered ) );

	// players always start with the base weapon
	RegisterItem( BG_FindItemForWeapon( WP_MACHINEGUN ) );
	RegisterItem( BG_FindItemForWeapon( WP_GAUNTLET ) );
#ifdef MISSIONPACK
	if( g_gametype.integer == GT_HARVESTER ) {
		RegisterItem( BG_FindItem( "Red Cube" ) );
		RegisterItem( BG_FindItem( "Blue Cube" ) );
	}
#endif
}

/*
===============
RegisterItem

The item will be added to the precache list
===============
*/
void RegisterItem( gitem_t *item ) {
	if ( !item ) {
		G_Error( "RegisterItem: NULL" );
	}
	itemRegistered[ item - bg_itemlist ] = qtrue;
}


/*
===============
SaveRegisteredItems

Write the needed items to a config string
so the client will know which ones to precache
===============
*/
void SaveRegisteredItems( void ) {
	char	string[MAX_ITEMS+1];
	int		i;
	int		count;

	count = 0;
	for ( i = 0 ; i < bg_numItems ; i++ ) {
		if ( itemRegistered[i] ) {
			count++;
			string[i] = '1';
		} else {
			string[i] = '0';
		}
	}
	string[ bg_numItems ] = 0;

	G_Printf( "%i items registered\n", count );
	trap_SetConfigstring(CS_ITEMS, string);
}

/*
============
G_ItemDisabled
============
*/
int G_ItemDisabled( gitem_t *item ) {

	char name[128];

	Com_sprintf(name, sizeof(name), "disable_%s", item->classname);
	return trap_Cvar_VariableIntegerValue( name );
}

/*
============
G_SpawnItem

Sets the clipping size and plants the object on the floor.

Items can't be immediately dropped to floor, because they might
be on an entity that hasn't spawned yet.
============
*/
void G_SpawnItem (gentity_t *ent, gitem_t *item) {
	G_SpawnFloat( "random", "0", &ent->random );
	G_SpawnFloat( "wait", "0", &ent->wait );

	RegisterItem( item );
	if ( G_ItemDisabled(item) )
		return;

	ent->item = item;
	// some movers spawn on the second frame, so delay item
	// spawns until the third frame so they can ride trains
	ent->nextthink = level.time + FRAMETIME * 2;
	ent->think = FinishSpawningItem;

	ent->physicsBounce = 0.50;		// items are bouncy

	if ( item->giType == IT_POWERUP ) {
		G_SoundIndex( "sound/items/poweruprespawn.wav" );
		G_SpawnFloat( "noglobalsound", "0", &ent->speed);
	}

#ifdef MISSIONPACK
	if ( item->giType == IT_PERSISTANT_POWERUP ) {
		ent->s.generic1 = ent->spawnflags;
	}
#endif
}


/*
================
G_BounceItem

================
*/
void G_BounceItem( gentity_t *ent, trace_t *trace ) {
	vec3_t	velocity;
	float	dot;
	int		hitTime;

	// reflect the velocity on the trace plane
	hitTime = level.previousTime + ( level.time - level.previousTime ) * trace->fraction;
	BG_EvaluateTrajectoryDelta( &ent->s.pos, hitTime, velocity );
	dot = DotProduct( velocity, trace->plane.normal );
	VectorMA( velocity, -2*dot, trace->plane.normal, ent->s.pos.trDelta );

	// cut the velocity to keep from bouncing forever
	VectorScale( ent->s.pos.trDelta, ent->physicsBounce, ent->s.pos.trDelta );

	// check for stop
	if ( trace->plane.normal[2] > 0 && ent->s.pos.trDelta[2] < 40 ) {
		trace->endpos[2] += 1.0;	// make sure it is off ground
		SnapVector( trace->endpos );
		G_SetOrigin( ent, trace->endpos );
		ent->s.groundEntityNum = trace->entityNum;
		return;
	}

	VectorAdd( ent->r.currentOrigin, trace->plane.normal, ent->r.currentOrigin);
	VectorCopy( ent->r.currentOrigin, ent->s.pos.trBase );
	ent->s.pos.trTime = level.time;
}


/*
================
G_RunItem

================
*/
void G_RunItem( gentity_t *ent ) {
	vec3_t		origin;
	trace_t		tr;
	int			contents;
	int			mask;

	// if groundentity has been set to -1, it may have been pushed off an edge
	if ( ent->s.groundEntityNum == -1 ) {
		if ( ent->s.pos.trType != TR_GRAVITY ) {
			ent->s.pos.trType = TR_GRAVITY;
			ent->s.pos.trTime = level.time;
		}
	}

	if ( ent->s.pos.trType == TR_STATIONARY ) {
		// check think function
		G_RunThink( ent );
		return;
	}

	// get current position
	BG_EvaluateTrajectory( &ent->s.pos, level.time, origin );

	// trace a line from the previous position to the current position
	if ( ent->clipmask ) {
		mask = ent->clipmask;
	} else {
		mask = MASK_PLAYERSOLID & ~CONTENTS_BODY;//MASK_SOLID;
	}
	trap_Trace( &tr, ent->r.currentOrigin, ent->r.mins, ent->r.maxs, origin, 
		ent->r.ownerNum, mask );

	VectorCopy( tr.endpos, ent->r.currentOrigin );

	if ( tr.startsolid ) {
		tr.fraction = 0;
	}

	trap_LinkEntity( ent );	// FIXME: avoid this for stationary?

	// check think function
	G_RunThink( ent );

	if ( tr.fraction == 1 ) {
		return;
	}

	// if it is in a nodrop volume, remove it
	contents = trap_PointContents( ent->r.currentOrigin, -1 );
	if ( contents & CONTENTS_NODROP ) {
		if (ent->item && ent->item->giType == IT_TEAM) {
			Team_FreeEntity(ent);
		} else {
			G_FreeEntity( ent );
		}
		return;
	}

	G_BounceItem( ent, &tr );
}