/*
===========================================================================

Return to Castle Wolfenstein multiplayer GPL Source Code
Copyright (C) 1999-2010 id Software LLC, a ZeniMax Media company. 

This file is part of the Return to Castle Wolfenstein multiplayer GPL Source Code (“RTCW MP Source Code”).  

RTCW MP Source Code is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

RTCW MP Source Code is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with RTCW MP Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the RTCW MP Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the RTCW MP Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

===========================================================================
*/

//===========================================================================
//
// Name:			ai_cast_sight.c
// Function:		Wolfenstein AI Character Visiblity
// Programmer:		Ridah
// Tab Size:		4 (real tabs)
//===========================================================================

#include "g_local.h"
#include "../qcommon/q_shared.h"
#include "../botlib/botlib.h"      //bot lib interface
#include "../botlib/be_aas.h"
#include "../botlib/be_ea.h"
#include "../botlib/be_ai_gen.h"
#include "../botlib/be_ai_goal.h"
#include "../botlib/be_ai_move.h"
#include "../botlib/botai.h"          //bot ai interface

#include "ai_cast.h"

/*
Does sight checking for Cast AI's.
*/

static float aiStateFovScales[] =
{
	1.0,    // relaxed
	1.5,    // query
	1.5,    // alert
	2.0,    // combat
};

/*
==============
AICast_InFieldOfVision
==============
*/
qboolean AICast_InFieldOfVision( vec3_t viewangles, float fov, vec3_t angles ) {
	int i;
	float diff, angle;

	for ( i = 0; i < 2; i++ )
	{
		angle = AngleMod( viewangles[i] );
		angles[i] = AngleMod( angles[i] );
		diff = angles[i] - angle;
		if ( angles[i] > angle ) {
			if ( diff > 180.0 ) {
				diff -= 360.0;
			}
		} else
		{
			if ( diff < -180.0 ) {
				diff += 360.0;
			}
		}
		if ( diff > 0 ) {
			if ( diff > fov * 0.5 ) {
				return qfalse;
			}
		} else
		{
			if ( diff < -fov * 0.5 ) {
				return qfalse;
			}
		}
	}
	return qtrue;
}

/*
==============
AICast_VisibleFromPos
==============
*/
qboolean AICast_VisibleFromPos( vec3_t srcpos, int srcnum,
								vec3_t destpos, int destnum, qboolean updateVisPos ) {
	int i, contents_mask, passent, hitent;
	trace_t trace;
	vec3_t start, end, middle, eye;
	cast_state_t        *cs = NULL;
	int srcviewheight;
	vec3_t destmins, destmaxs;
	vec3_t right, vec;
	qboolean inPVS;

	if ( g_entities[destnum].flags & FL_NOTARGET ) {
		return qfalse;
	}

	if ( srcnum < aicast_maxclients ) {
		cs = AICast_GetCastState( srcnum );
	}
	//
	if ( cs && cs->bs ) {
		srcviewheight = cs->bs->cur_ps.viewheight;
	} else if ( g_entities[srcnum].client ) {
		srcviewheight = g_entities[srcnum].client->ps.viewheight;
	} else {
		srcviewheight = 0;
	}
	//
	VectorCopy( g_entities[destnum].r.mins, destmins );
	VectorCopy( g_entities[destnum].r.maxs, destmaxs );
	//
	//calculate middle of bounding box
	VectorAdd( destmins, destmaxs, middle );
	VectorScale( middle, 0.5, middle );
	VectorAdd( destpos, middle, middle );
	// calculate eye position
	VectorCopy( srcpos, eye );
	eye[2] += srcviewheight;
	//
	// set the right vector
	VectorSubtract( middle, eye, vec );
	VectorNormalize( vec );
	right[0] = vec[1];
	right[1] = vec[0];
	right[2] = 0;
	//
	inPVS = qfalse;
	//
	for ( i = 0; i < 5; i++ )
	{
		if ( cs && updateVisPos ) {   // if it's a grenade or something, PVS checks don't work very well
			//if the point is not in potential visible sight
			if ( i < 3 ) {    // don't do PVS check for left/right checks
				if ( !trap_InPVS( eye, middle ) ) {
					continue;
				} else {
					inPVS = qtrue;
				}
			} else if ( !inPVS ) {
				break;      // wasn't in potential view in either of the previous tests
			}               // so don't bother doing left/right
		}
		//
		contents_mask = MASK_SHOT & ~CONTENTS_BODY; // we can see anything that a bullet can pass through
		passent = srcnum;
		hitent = destnum;
		VectorCopy( eye, start );
		VectorCopy( middle, end );
		//if the entity is in water, lava or slime
		if ( trap_PointContents( middle, destnum ) & ( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER ) ) {
			contents_mask |= ( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER );
		} //end if
		  //if eye is in water, lava or slime
		if ( trap_PointContents( eye, srcnum ) & ( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER ) ) {
			if ( !( contents_mask & ( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER ) ) ) {
				passent = destnum;
				hitent = srcnum;
				VectorCopy( middle, start );
				VectorCopy( eye, end );
			} //end if
			contents_mask ^= ( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER );
		} //end if
		  //trace from start to end
		trap_Trace( &trace, start, NULL, NULL, end, ENTITYNUM_NONE /*passent*/, contents_mask );
		//if water was hit
		if ( trace.contents & ( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER ) ) {
			//if the water surface is translucent
//			if (trace.surface.flags & (SURF_TRANS33|SURF_TRANS66))
			{
				//trace through the water
				contents_mask &= ~( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER );
				trap_Trace( &trace, trace.endpos, NULL, NULL, end, passent, contents_mask );
			} //end if
		} //end if
		  //if a full trace or the hitent was hit
		if ( trace.fraction >= 1 || trace.entityNum == hitent ) {
			return qtrue;
		}
		//check bottom and top of bounding box as well
		if ( i == 0 ) {
			middle[2] -= ( destmaxs[2] - destmins[2] ) * 0.5;
		} else if ( i == 1 ) {
			middle[2] += destmaxs[2] - destmins[2];
		} else if ( i == 2 )                                                          { // right side
			middle[2] -= ( destmaxs[2] - destmins[2] ) / 2.0;
			VectorMA( eye, destmaxs[0] - 0.5, right, eye );
		} else if ( i == 3 ) {    // left side
			VectorMA( eye, -2.0 * ( destmaxs[0] - 0.5 ), right, eye );
		}
	} //end for

	return qfalse;
}

/*
==============
AICast_CheckVisibility
==============
*/
qboolean AICast_CheckVisibility( gentity_t *srcent, gentity_t *destent ) {
	vec3_t dir, entangles, middle, eye, viewangles;
	cast_state_t        *cs;
	float fov, dist;
	int viewer, ent;
	orientation_t       or;

	if ( destent->flags & FL_NOTARGET ) {
		return qfalse;
	}
	//
	viewer = srcent->s.number;
	ent = destent->s.number;
	//
	cs = AICast_GetCastState( viewer );
	AICast_GetCastState( ent );
	// set the FOV
	fov = cs->attributes[FOV] * aiStateFovScales[cs->aiState];
	if ( !fov ) { // assume it's a player, give them a generic fov
		fov = 180;
	}
	if ( cs->aiFlags & AIFL_ZOOMING ) {
		fov *= 0.8;
	}
	//calculate middle of bounding box
	VectorAdd( destent->r.mins, destent->r.maxs, middle );
	VectorScale( middle, 0.5, middle );
	VectorAdd( destent->client->ps.origin, middle, middle );
	// calculate eye position
	if ( srcent->r.svFlags & SVF_CASTAI ) {
		if ( trap_GetTag( srcent->s.number, "tag_head", &or ) ) {
			// use the actual direction the head is facing
			vectoangles( or.axis[0], viewangles );
			// and the actual position of the head
			VectorCopy( or.origin, eye );
		} else {
			VectorCopy( srcent->client->ps.origin, eye );
			eye[2] += srcent->client->ps.viewheight;
			VectorCopy( srcent->client->ps.viewangles, viewangles );
		}
	} else {
		VectorCopy( srcent->client->ps.origin, eye );
		eye[2] += srcent->client->ps.viewheight;
		VectorCopy( srcent->client->ps.viewangles, viewangles );
	}
	//check if entity is within field of vision
	VectorSubtract( middle, eye, dir );
	vectoangles( dir, entangles );
	//
	dist = VectorLength( dir );
	//
	// alertness is visible range
	if ( cs->bs && dist > cs->attributes[ALERTNESS] ) {
		return qfalse;
	}
	// check FOV
	if ( !AICast_InFieldOfVision( viewangles, fov, entangles ) ) {
		return qfalse;
	}
	//
	if ( !AICast_VisibleFromPos( srcent->client->ps.origin, srcent->s.number, destent->client->ps.origin, destent->s.number, qtrue ) ) {
		return qfalse;
	}
	//
	return qtrue;
}

/*
==============
AICast_UpdateVisibility
==============
*/
void AICast_UpdateVisibility( gentity_t *srcent, gentity_t *destent, qboolean shareVis, qboolean directview ) {
	cast_visibility_t   *vis, *ovis, *svis, oldvis;
	cast_state_t        *cs, *ocs;
	qboolean shareRange;
	int cnt, i;

	if ( destent->flags & FL_NOTARGET ) {
		return;
	}

	cs = AICast_GetCastState( srcent->s.number );
	ocs = AICast_GetCastState( destent->s.number );

	if ( cs->castScriptStatus.scriptNoSightTime >= level.time ) {
		return;     // absolutely no sight (or hear) information allowed

	}
	shareRange = ( VectorDistance( srcent->client->ps.origin, destent->client->ps.origin ) < AIVIS_SHARE_RANGE );

	vis = &cs->vislist[destent->s.number];

	vis->chase_marker_count = 0;

	if ( aicast_debug.integer == 1 ) {
		if ( !vis->visible_timestamp || vis->visible_timestamp < level.time - 5000 ) {
			if ( directview ) {
				G_Printf( "SIGHT (direct): %s sees %s\n", srcent->aiName, destent->aiName );
			} else {
				G_Printf( "SIGHT (non-direct/audible): %s sees %s\n", srcent->aiName, destent->aiName );
			}
		}
	}

	// trigger the sight event
	AICast_Sight( srcent, destent, vis->visible_timestamp );

	// update the values
	vis->lastcheck_timestamp = level.time;
	vis->visible_timestamp = level.time;
	VectorCopy( destent->client->ps.origin, vis->visible_pos );
	VectorCopy( destent->client->ps.velocity, vis->visible_vel );

	// we may need to process this visibility at some point, even after they become not visible again
	vis->flags |= AIVIS_PROCESS_SIGHTING;

	if ( directview ) {
		vis->real_visible_timestamp = level.time;
		VectorCopy( destent->client->ps.origin, vis->real_visible_pos );
		vis->real_update_timestamp = level.time;
	}

	// if we are on fire, then run away from anything we see
	if ( cs->attributes[AGGRESSION] < 1.0 && srcent->s.onFireEnd > level.time && ( !destent->s.number || cs->dangerEntityValidTime < level.time + 2000 ) && !( cs->aiFlags & AIFL_NO_FLAME_DAMAGE ) ) {
		cs->dangerEntity = destent->s.number;
		VectorCopy( destent->r.currentOrigin, cs->dangerEntityPos );
		cs->dangerEntityValidTime = level.time + 5000;
		cs->dangerDist = 99999;
		cs->dangerEntityTimestamp = level.time;
	}

	// Look for reasons to make this character an enemy of ours

	// if they are an enemy and inside the detection radius, go hostile
	if ( !( vis->flags & AIVIS_ENEMY ) && !AICast_SameTeam( cs, destent->s.number ) ) {
		float idr;

		idr = cs->attributes[INNER_DETECTION_RADIUS];
		if ( cs->aiFlags & AIFL_ZOOMING ) {
			idr *= 10;
		}
		if ( !( vis->flags & AIVIS_ENEMY ) && VectorDistance( vis->visible_pos, g_entities[cs->entityNum].r.currentOrigin ) < idr ) {
			// RF, moved them over to AICast_ScanForEnemies()
			//AICast_ScriptEvent( cs, "enemysight", destent->aiName );
			vis->flags |= AIVIS_ENEMY;
		}
		// if we are in (or above) ALERT mode, then we now know this is an enemy
		else if ( cs->aiState >= AISTATE_ALERT ) {
			// RF, moved them over to AICast_ScanForEnemies()
			//AICast_ScriptEvent( cs, "enemysight", destent->aiName );
			vis->flags |= AIVIS_ENEMY;
		}
	}

	// if they are friendly, then we should help them out if they are in trouble
	if ( AICast_SameTeam( cs, destent->s.number ) && ( srcent->aiTeam == AITEAM_ALLIES || srcent->aiTeam == AITEAM_NAZI ) ) {
		// if they are dead, we should check them out
		if ( destent->health <= 0 ) {
			// if we haven't already checked them out
			if ( !( vis->flags & AIVIS_INSPECTED ) ) {
				vis->flags |= AIVIS_INSPECT;
			}
			// if they are mad, we should help, or at least act concerned
		} else if ( cs->aiState < AISTATE_COMBAT && ocs->aiState >= AISTATE_COMBAT && ocs->bs && ( ocs->bs->enemy >= 0 ) ) {
			// if we haven't already checked them out
			if ( !( vis->flags & AIVIS_INSPECTED ) ) {
				vis->flags |= AIVIS_INSPECT;
			}
			// if they are alert, we should also go alert
		} else if ( cs->aiState < AISTATE_ALERT && ocs->aiState == AISTATE_ALERT && ocs->bs ) {
			AICast_StateChange( cs, AISTATE_ALERT );
		}
	}

	// if this is a friendly, then check them for hostile's that we currently haven't upgraded so

	if ( ( destent->health > 0 ) &&
		 ( srcent->aiTeam == destent->aiTeam ) && // only share with exact same team, and non-neutrals
		 ( srcent->aiTeam != AITEAM_NEUTRAL ) ) {
		ocs = AICast_GetCastState( destent->s.number );
		cnt = 0;
		//
		for ( i = 0; i < aicast_maxclients && cnt < level.numPlayingClients; i++ ) {
			if ( !g_entities[i].inuse ) {
				continue;
			}
			//
			cnt++;
			//
			if ( i == srcent->s.number ) {
				continue;
			}
			if ( i == destent->s.number ) {
				continue;
			}
			//
			ovis = &ocs->vislist[i];
			svis = &cs->vislist[i];
			//
			// if we are close to the friendly, then we should share their visibility info
			if ( destent->health > 0 && shareRange ) {
				// if they have seen this character more recently than us, share
				if ( ovis->visible_timestamp > svis->visible_timestamp ) {
					// trigger an EVENT

					// trigger the sight event
					AICast_Sight( srcent, destent, ovis->visible_timestamp );

					// we may need to process this visibility at some point, even after they become not visible again
					svis->flags |= AIVIS_PROCESS_SIGHTING;

					// if we are sharing information about an enemy, then trigger a scripted event
					if ( !svis->real_visible_timestamp && ovis->real_visible_timestamp && ( ovis->flags & AIVIS_ENEMY ) ) {
						// setup conditions
						BG_UpdateConditionValue( ocs->entityNum, ANIM_COND_ENEMY_TEAM, g_entities[i].aiTeam, qfalse );
						// call the event
						BG_AnimScriptEvent( &g_entities[ocs->entityNum].client->ps, ANIM_ET_INFORM_FRIENDLY_OF_ENEMY, qfalse, qfalse );
					}
					oldvis = *svis;
					// copy the whole structure
					*svis = *ovis;
					// minus the flags
					svis->flags = oldvis.flags;
					// check to see if we just made this character an enemy of ours
					if ( ( cs->aiState == AISTATE_COMBAT ) && ( ovis->flags & AIVIS_ENEMY ) && !( oldvis.flags & AIVIS_ENEMY ) ) {
						svis->flags |= AIVIS_ENEMY;
						AICast_ScriptEvent( cs, "enemysight", g_entities[i].aiName );
						if ( !( cs->aiFlags & AIFL_DENYACTION ) ) {
							G_AddEvent( srcent, EV_GENERAL_SOUND, G_SoundIndex( aiDefaults[cs->aiCharacter].sightSoundScript ) );
						}
					}
				}
			} else {
				// if either of us haven't seen this character yet, then ignore it
				if ( !svis->visible_timestamp || !ovis->visible_timestamp ) {
					continue;
				}
			}
			//
			// if they have marked this character as hostile, then we should also
			if ( ( cs->aiState == AISTATE_COMBAT ) && AICast_HostileEnemy( ocs, i ) && !AICast_HostileEnemy( cs, i ) ) {
				AICast_ScriptEvent( cs, "enemysight", g_entities[i].aiName );
				if ( !( cs->aiFlags & AIFL_DENYACTION ) ) {
					G_AddEvent( srcent, EV_GENERAL_SOUND, G_SoundIndex( aiDefaults[cs->aiCharacter].sightSoundScript ) );
				}
				svis->flags |= AIVIS_ENEMY;
			}
		}
	}
}

/*
==============
AICast_UpdateNonVisibility
==============
*/
void AICast_UpdateNonVisibility( gentity_t *srcent, gentity_t *destent, qboolean directview ) {
	cast_visibility_t   *vis;
	cast_state_t        *cs;

	cs = AICast_GetCastState( srcent->s.number );

	vis = &cs->vislist[destent->s.number];

	// update the values
	vis->lastcheck_timestamp = level.time;
	vis->notvisible_timestamp = level.time;

	if ( directview ) {
		vis->real_update_timestamp = level.time;
		vis->real_notvisible_timestamp = level.time;
	}

	// if enough time has passed, and still within chase period, drop a marker
	if ( vis->chase_marker_count < MAX_CHASE_MARKERS ) {
		if ( ( level.time - vis->visible_timestamp ) > ( vis->chase_marker_count + 1 ) * CHASE_MARKER_INTERVAL ) {
			VectorCopy( destent->client->ps.origin, vis->chase_marker[vis->chase_marker_count] );
			vis->chase_marker_count++;
		}
	}
}

/*
==============
AICast_SightSoundEvent

  this cast has made a sound which should be heard by others
==============
*/
void AICast_SightSoundEvent( cast_state_t *cs, float range ) {
	int i;
	cast_state_t *ocs;
	gentity_t   *oent, *ent;

	ent = &g_entities[cs->entityNum];
	if ( ent->flags & FL_NOTARGET ) {
		return;
	}
	for ( i = 0, ocs = caststates, oent = g_entities; i < level.maxclients; i++, ocs++, oent++ ) {
		if ( !oent->inuse ) {
			continue;
		}
		if ( oent->aiInactive ) {
			continue;
		}
		if ( !ocs->bs ) {
			continue;
		}
		if ( oent->health <= 0 ) {
			continue;
		}
		if ( Distance( oent->r.currentOrigin, ent->r.currentOrigin ) > range * ocs->attributes[HEARING_SCALE] ) {
			continue;
		}
		// they heard us
		AICast_UpdateVisibility( oent, ent, qfalse, qfalse );
	}
}

/*
==============
AICast_SightUpdate
==============
*/
static int lastsrc = 0, lastdest = 0;

void AICast_SightUpdate( int numchecks ) {
	int count = 0, destcount, srccount;
	int src = 0, dest = 0;
	gentity_t       *srcent, *destent;
	cast_state_t    *cs;
	cast_visibility_t *vis;

	if ( numchecks < 5 ) {
		numchecks = 5;
	}

	if ( trap_Cvar_VariableIntegerValue( "savegame_loading" ) ) {
		return;
	}

	if ( saveGamePending ) {
		return;
	}

	// First, check all REAL clients, so sighting player is only effected by reaction_time, not
	// effected by framerate also
	for (   srccount = 0, src = 0, srcent = &g_entities[0];
			src < aicast_maxclients && srccount < level.numPlayingClients;
			src++, srcent++ )
	{
		if ( !srcent->inuse ) {
			continue;
		}

		srccount++;

		if ( srcent->aiInactive ) {
			continue;
		}
		if ( srcent->health <= 0 ) {
			continue;
		}
		if ( !( srcent->r.svFlags & SVF_CASTAI ) ) { // only source check AI Cast
			continue;
		}

		cs = AICast_GetCastState( src );

		if ( cs->castScriptStatus.scriptNoSightTime >= level.time ) {
			continue;
		}

		// make sure we are using the right AAS data for this entity (one's that don't get set will default to the player's AAS data)
		trap_AAS_SetCurrentWorld( cs->aasWorldIndex );

		for (   destcount = 0, dest = 0, destent = &g_entities[0];
				dest < aicast_maxclients && destcount < level.numPlayingClients;
				dest++, destent++ )
		{
			if ( !destent->inuse ) {
				continue;
			}

			destcount++;

			if ( destent->health <= 0 ) {
				continue;
			}
			if ( destent->r.svFlags & SVF_CASTAI ) {      // only dest check REAL clients
				continue;
			}

			if ( src == dest ) {
				continue;
			}

			vis = &cs->vislist[destent->s.number];

			// if we saw them last frame, skip this test, so we only check initial sightings each frame
			if ( vis->lastcheck_timestamp == vis->real_visible_timestamp ) {
				continue;
			}

			// if we recently checked this vis, skip
			if ( vis->lastcheck_timestamp >= level.time - 100 ) {
				continue;
			}

			if ( vis->lastcheck_timestamp > level.time ) {
				continue;   // let the loadgame settle down

			}
			// check for visibility
			if (    !( destent->flags & FL_NOTARGET )
					&&  ( AICast_CheckVisibility( srcent, destent ) ) ) {
				// record the sighting
				AICast_UpdateVisibility( srcent, destent, qtrue, qtrue );
			} else // if (vis->lastcheck_timestamp == vis->real_update_timestamp)
			{
				AICast_UpdateNonVisibility( srcent, destent, qtrue );
			}
		}
	}

	// Now do the normal timeslice checks
	for (   srccount = 0, src = lastsrc, srcent = &g_entities[lastsrc];
			src < aicast_maxclients; // && srccount < level.numPlayingClients;
			src++, srcent++ )
	{
		if ( !srcent->inuse ) {
			continue;
		}

		srccount++;

		if ( srcent->aiInactive ) {
			continue;
		}
		if ( srcent->health <= 0 ) {
			continue;
		}

		cs = AICast_GetCastState( src );

		if ( cs->castScriptStatus.scriptNoSightTime >= level.time ) {
			continue;
		}

		// make sure we are using the right AAS data for this entity (one's that don't get set will default to the player's AAS data)
		trap_AAS_SetCurrentWorld( cs->aasWorldIndex );

		if ( lastdest < 0 ) {
			lastdest = 0;
		}

		for (   destcount = 0, dest = lastdest, destent = &g_entities[lastdest];
				dest < aicast_maxclients; // && destcount < level.numPlayingClients;
				dest++, destent++ )
		{
			if ( !destent->inuse ) {
				continue;
			}

			destcount++;

			if ( destent->aiInactive ) {
				continue;
			}
			if ( src == dest ) {
				continue;
			}

			vis = &cs->vislist[destent->s.number];

			// we only check for initial sighting above
			if ( !( destent->r.svFlags & SVF_CASTAI ) ) {
				if ( vis->lastcheck_timestamp != vis->real_visible_timestamp ) {
					continue;
				}
			}

			if ( vis->lastcheck_timestamp == level.time ) {
				continue;   // already checked this frame
			}

			if ( vis->lastcheck_timestamp > level.time ) {
				continue;   // let the loadgame settle down

			}

			// if they are friends, only check very infrequently
			if ( AICast_SameTeam( cs, destent->s.number ) && ( vis->lastcheck_timestamp == vis->visible_timestamp )
				 && ( destent->health == vis->lastcheck_health ) ) {
				if ( vis->lastcheck_timestamp > ( level.time - ( 2000 + rand() % 1000 ) ) ) {
					continue;   // dont check too often
				}
			}

			// check for visibility
			if (    !( destent->flags & FL_NOTARGET )
					&&  ( AICast_CheckVisibility( srcent, destent ) ) ) {
				// make sure they are still with us
				if ( destent->inuse ) {
					// record the sighting
					AICast_UpdateVisibility( srcent, destent, qtrue, qtrue );
				}
			} else // if (vis->lastcheck_timestamp == vis->real_update_timestamp)
			{
				AICast_UpdateNonVisibility( srcent, destent, qtrue );
			}

			// break if we've processed the maximum visibilities
			if ( ++count > numchecks ) {
				dest++;
				if ( dest >= aicast_maxclients ) {
					src++;
				}
				goto escape;
			}
		}

		lastdest = 0;
	}

escape:

	if ( src >= aicast_maxclients ) {
		src = 0;
	}
	lastsrc = src;
	if ( dest >= aicast_maxclients ) {
		dest = 0;
	}
	lastdest = dest;
}