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/cvs/deliantra/server/server/monster.c
Revision: 1.3
Committed: Fri Mar 10 14:08:38 2006 UTC (18 years, 2 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.2: +2 -2 lines
Log Message:
Another crash-fix: it seems scrolls can be legally empty

File Contents

# User Rev Content
1 root 1.1 /*
2     * static char *rcsid_monster_c =
3 root 1.3 * "$Id$";
4 root 1.1 */
5    
6     /*
7     CrossFire, A Multiplayer game for X-windows
8    
9     Copyright (C) 2002 Mark Wedel & Crossfire Development Team
10     Copyright (C) 1992 Frank Tore Johansen
11    
12     This program is free software; you can redistribute it and/or modify
13     it under the terms of the GNU General Public License as published by
14     the Free Software Foundation; either version 2 of the License, or
15     (at your option) any later version.
16    
17     This program is distributed in the hope that it will be useful,
18     but WITHOUT ANY WARRANTY; without even the implied warranty of
19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20     GNU General Public License for more details.
21    
22     You should have received a copy of the GNU General Public License
23     along with this program; if not, write to the Free Software
24     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25    
26     The authors can be reached via e-mail at crossfire-devel@real-time.com
27     */
28    
29     #include <global.h>
30     #ifndef __CEXTRACT__
31     #include <sproto.h>
32     #include <spells.h>
33     #include <skills.h>
34     #endif
35    
36    
37     #define MIN_MON_RADIUS 3 /* minimum monster detection radius */
38    
39    
40     /* checks npc->enemy and returns that enemy if still valid,
41     * NULL otherwise.
42     * this is map tile aware.
43     * If this returns an enemy, the range vector rv should also be
44     * set to sane values.
45     */
46     object *check_enemy(object *npc, rv_vector *rv) {
47    
48     /* if this is pet, let him attack the same enemy as his owner
49     * TODO: when there is no ower enemy, try to find a target,
50     * which CAN attack the owner. */
51     if ((npc->attack_movement & HI4) == PETMOVE)
52     {
53     if (npc->owner == NULL)
54     npc->enemy = NULL;
55     else if (npc->enemy == NULL)
56     npc->enemy = npc->owner->enemy;
57     }
58    
59     /* periodically, a monster mayu change its target. Also, if the object
60     * has been destroyed, etc, clear the enemy.
61     * TODO: this should be changed, because it invokes to attack forced or
62     * attacked monsters to leave the attacker alone, before it is destroyed
63     */
64     /* i had removed the random target leave, this invokes problems with friendly
65     * objects, getting attacked and defending herself - they don't try to attack
66     * again then but perhaps get attack on and on
67     * If we include a aggravated flag in , we can handle evil vs evil and good vs good
68     * too. */
69    
70     if(npc->enemy)
71     {
72     /* I broke these if's apart to better be able to see what
73     * the grouping checks are. Code is the same.
74     */
75     if ( QUERY_FLAG(npc->enemy,FLAG_REMOVED) ||
76     QUERY_FLAG(npc->enemy,FLAG_FREED) ||
77     !on_same_map(npc, npc->enemy) ||
78     npc == npc->enemy ||
79     QUERY_FLAG(npc, FLAG_NEUTRAL) ||
80     QUERY_FLAG(npc->enemy, FLAG_NEUTRAL))
81     npc->enemy = NULL;
82    
83     else if (QUERY_FLAG(npc, FLAG_FRIENDLY) && (
84     (QUERY_FLAG(npc->enemy, FLAG_FRIENDLY) && !(should_arena_attack(npc, npc->owner, npc->enemy))) ||
85     ((npc->enemy->type == PLAYER) && !(should_arena_attack(npc, npc->owner, npc->enemy)))
86     || npc->enemy == npc->owner))
87     npc->enemy = NULL;
88    
89    
90     else if (!QUERY_FLAG(npc, FLAG_FRIENDLY) &&
91     (!QUERY_FLAG(npc->enemy, FLAG_FRIENDLY) && npc->enemy->type!=PLAYER))
92     npc->enemy=NULL;
93    
94     /* I've noticed that pets could sometimes get an arrow as the
95     * target enemy - this code below makes sure the enemy is something
96     * that should be attacked. My guess is that the arrow hits
97     * the creature/owner, and so the creature then takes that
98     * as the enemy to attack.
99     */
100     else if (!QUERY_FLAG(npc->enemy, FLAG_MONSTER) &&
101     !QUERY_FLAG(npc->enemy,FLAG_GENERATOR) &&
102     npc->enemy->type!=PLAYER && npc->enemy->type != GOLEM)
103     npc->enemy=NULL;
104    
105     }
106     return can_detect_enemy(npc,npc->enemy,rv)?npc->enemy:NULL;
107     }
108    
109     /* Returns the nearest living creature (monster or generator).
110     * Modified to deal with tiled maps properly.
111     * Also fixed logic so that monsters in the lower directions were more
112     * likely to be skipped - instead of just skipping the 'start' number
113     * of direction, revisit them after looking at all the other spaces.
114     *
115     * Note that being this may skip some number of spaces, it will
116     * not necessarily find the nearest living creature - it basically
117     * chooses one from within a 3 space radius, and since it skips
118     * the first few directions, it could very well choose something
119     * 3 spaces away even though something directly north is closer.
120     *
121     * this function is map tile aware.
122     */
123     object *find_nearest_living_creature(object *npc) {
124     int i,mflags;
125     sint16 nx,ny;
126     mapstruct *m;
127     object *tmp;
128     int search_arr[SIZEOFFREE];
129    
130     get_search_arr(search_arr);
131     for(i=0;i<SIZEOFFREE;i++) {
132     /* modified to implement smart searching using search_arr
133     * guidance array to determine direction of search order
134     */
135     nx = npc->x + freearr_x[search_arr[i]];
136     ny = npc->y + freearr_y[search_arr[i]];
137     m = npc->map;
138    
139     mflags = get_map_flags(m, &m, nx, ny, &nx, &ny);
140     if (mflags & P_OUT_OF_MAP) continue;
141    
142     if (mflags & P_IS_ALIVE) {
143     tmp=get_map_ob(m,nx,ny);
144     while(tmp!=NULL && !QUERY_FLAG(tmp,FLAG_MONSTER)&&
145     !QUERY_FLAG(tmp,FLAG_GENERATOR ) && tmp->type!=PLAYER)
146     tmp=tmp->above;
147    
148     if (!tmp) {
149     LOG(llevDebug,"find_nearest_living_creature: map %s (%d,%d) has is_alive set but did not find a monster?\n",
150     m->path, nx, ny);
151     }
152     else {
153     if(can_see_monsterP(m,nx,ny,i))
154     return tmp;
155     }
156     } /* is something living on this space */
157     }
158     return NULL; /* nothing found */
159     }
160    
161    
162     /* Tries to find an enmy for npc. We pass the range vector since
163     * our caller will find the information useful.
164     * Currently, only move_monster calls this function.
165     * Fix function so that we always make calls to get_rangevector
166     * if we have a valid target - function as not doing so in
167     * many cases.
168     */
169    
170     object *find_enemy(object *npc, rv_vector *rv)
171     {
172     object *attacker, *tmp=NULL;
173    
174     attacker = npc->attacked_by; /* save this for later use. This can be a attacker. */
175     npc->attacked_by = NULL; /* always clear the attacker entry */
176    
177     /* if we berserk, we don't care about others - we attack all we can find */
178     if(QUERY_FLAG(npc,FLAG_BERSERK)) {
179     tmp = find_nearest_living_creature(npc);
180     if (tmp) get_rangevector(npc, tmp, rv, 0);
181     return tmp;
182     }
183    
184     /* Here is the main enemy selection.
185     * We want this: if there is an enemy, attack him until its not possible or
186     * one of both is dead.
187     * If we have no enemy and we are...
188     * a monster: try to find a player, a pet or a friendly monster
189     * a friendly: only target a monster which is targeting you first or targeting a player
190     * a neutral: fight a attacker (but there should be none), then do nothing
191     * a pet: attack player enemy or a monster
192     */
193    
194     /* pet move */
195     if ((npc->attack_movement & HI4) == PETMOVE) {
196     tmp= get_pet_enemy(npc,rv);
197     if (tmp) get_rangevector(npc, tmp, rv, 0);
198     return tmp;
199     }
200    
201     /* we check our old enemy. */
202     if((tmp=check_enemy(npc, rv))==NULL)
203     {
204     if(attacker) /* if we have an attacker, check him */
205     {
206     /* we want be sure this is the right one! */
207     if(attacker->count == npc->attacked_by_count)
208     {
209     /* TODO: thats not finished */
210     /* we don't want a fight evil vs evil or good against non evil */
211    
212     if( QUERY_FLAG(npc, FLAG_NEUTRAL) || QUERY_FLAG(attacker, FLAG_NEUTRAL) || /* neutral */
213     (QUERY_FLAG(npc, FLAG_FRIENDLY) && QUERY_FLAG(attacker, FLAG_FRIENDLY)) ||
214     (!QUERY_FLAG(npc, FLAG_FRIENDLY) &&
215     (!QUERY_FLAG(attacker, FLAG_FRIENDLY) && attacker->type!=PLAYER)) )
216     CLEAR_FLAG(npc,FLAG_SLEEP); /* skip it, but lets wakeup */
217     else if(on_same_map(npc, attacker)) /* thats the only thing we must know... */
218     {
219     CLEAR_FLAG(npc,FLAG_SLEEP); /* well, NOW we really should wake up! */
220     npc->enemy = attacker;
221     return attacker; /* yes, we face our attacker! */
222     }
223     }
224     }
225    
226     /* we have no legal enemy or attacker, so we try to target a new one */
227     if(!QUERY_FLAG(npc, FLAG_UNAGGRESSIVE) && !QUERY_FLAG(npc, FLAG_FRIENDLY) &&
228     !QUERY_FLAG(npc, FLAG_NEUTRAL))
229     {
230     npc->enemy = get_nearest_player(npc);
231     if (npc->enemy)
232     tmp = check_enemy(npc,rv);
233     }
234    
235     }
236    
237     return tmp;
238     }
239    
240     /* Sees if this monster should wake up.
241     * Currently, this is only called from move_monster, and
242     * if enemy is set, then so should be rv.
243     * returns 1 if the monster should wake up, 0 otherwise.
244     */
245    
246     int check_wakeup(object *op, object *enemy, rv_vector *rv) {
247     int radius = op->stats.Wis>MIN_MON_RADIUS?op->stats.Wis:MIN_MON_RADIUS;
248    
249     /* Trim work - if no enemy, no need to do anything below */
250     if (!enemy) return 0;
251    
252     /* blinded monsters can only find nearby objects to attack */
253     if(QUERY_FLAG(op, FLAG_BLIND))
254     radius = MIN_MON_RADIUS;
255    
256     /* This covers the situation where the monster is in the dark
257     * and has an enemy. If the enemy has no carried light (or isnt
258     * glowing!) then the monster has trouble finding the enemy.
259     * Remember we already checked to see if the monster can see in
260     * the dark. */
261    
262     else if(op->map && op->map->darkness>0 && enemy && !enemy->invisible &&
263     !stand_in_light(enemy) &&
264     (!QUERY_FLAG(op,FLAG_SEE_IN_DARK) || !QUERY_FLAG(op,FLAG_SEE_INVISIBLE))) {
265     int dark = radius/(op->map->darkness);
266     radius = (dark>MIN_MON_RADIUS)?(dark+1):MIN_MON_RADIUS;
267     }
268     else if(!QUERY_FLAG(op,FLAG_SLEEP)) return 1;
269    
270     /* enemy should already be on this map, so don't really need to check
271     * for that.
272     */
273     if (rv->distance < (QUERY_FLAG(enemy, FLAG_STEALTH)?(radius/2)+1:radius)) {
274     CLEAR_FLAG(op,FLAG_SLEEP);
275     return 1;
276     }
277     return 0;
278     }
279    
280     int move_randomly(object *op) {
281     int i;
282    
283     /* Give up to 15 chances for a monster to move randomly */
284     for(i=0;i<15;i++) {
285     if(move_object(op,RANDOM()%8+1))
286     return 1;
287     }
288     return 0;
289     }
290    
291     /*
292     * Move-monster returns 1 if the object has been freed, otherwise 0.
293     */
294    
295     int move_monster(object *op) {
296     int dir, diff;
297     object *owner, *enemy, *part, *oph=op;
298     rv_vector rv;
299    
300     /* Monsters not on maps don't do anything. These monsters are things
301     * Like royal guards in city dwellers inventories.
302     */
303     if (!op->map) return 0;
304    
305     /* for target facing, we copy this value here for fast access */
306     if(oph->head) /* force update the head - one arch one pic */
307     oph = oph->head;
308    
309     if (QUERY_FLAG(op, FLAG_NO_ATTACK)) /* we never ever attack */
310     enemy = op->enemy = NULL;
311     else if((enemy= find_enemy(op, &rv)))
312     {
313     /* we have an enemy, just tell him we want him dead */
314     enemy->attacked_by = op; /* our ptr */
315     enemy->attacked_by_count = op->count; /* our tag */
316     }
317    
318     if ( QUERY_FLAG(op, FLAG_SLEEP) || QUERY_FLAG(op, FLAG_BLIND) ||
319     ((op->map->darkness>0) && !QUERY_FLAG(op,FLAG_SEE_IN_DARK) &&
320     !QUERY_FLAG(op,FLAG_SEE_INVISIBLE))) {
321     if(!check_wakeup(op,enemy,&rv))
322     return 0;
323     }
324    
325     /* check if monster pops out of hidden spot */
326     if(op->hide) do_hidden_move(op);
327    
328     if(op->pick_up)
329     monster_check_pickup(op);
330    
331     if(op->will_apply)
332     monster_apply_below(op); /* Check for items to apply below */
333    
334     /* generate hp, if applicable */
335     if(op->stats.Con > 0 && op->stats.hp < op->stats.maxhp) {
336    
337     /* last heal is in funny units. Dividing by speed puts
338     * the regeneration rate on a basis of time instead of
339     * #moves the monster makes. The scaling by 8 is
340     * to capture 8th's of a hp fraction regens
341     *
342     * Cast to sint32 before comparing to maxhp since otherwise an (sint16)
343     * overflow might produce monsters with negative hp.
344     */
345    
346     op->last_heal+= (int)((float)(8*op->stats.Con)/FABS(op->speed));
347     op->stats.hp = MIN((sint32)op->stats.hp+op->last_heal/32, op->stats.maxhp); /* causes Con/4 hp/tick */
348     op->last_heal%=32;
349    
350     /* So if the monster has gained enough HP that they are no longer afraid */
351     if (QUERY_FLAG(op,FLAG_RUN_AWAY) &&
352     op->stats.hp >= (signed short)(((float)op->run_away/(float)100)*
353     (float)op->stats.maxhp))
354     CLEAR_FLAG(op, FLAG_RUN_AWAY);
355    
356     if(op->stats.hp>op->stats.maxhp)
357     op->stats.hp=op->stats.maxhp;
358     }
359    
360     /* generate sp, if applicable */
361     if(op->stats.Pow > 0 && op->stats.sp < op->stats.maxsp) {
362    
363     /* last_sp is in funny units. Dividing by speed puts
364     * the regeneration rate on a basis of time instead of
365     * #moves the monster makes. The scaling by 8 is
366     * to capture 8th's of a sp fraction regens
367     *
368     * Cast to sint32 before comparing to maxhp since otherwise an (sint16)
369     * overflow might produce monsters with negative sp.
370     */
371    
372     op->last_sp+= (int)((float)(8*op->stats.Pow)/FABS(op->speed));
373     op->stats.sp = MIN(op->stats.sp+op->last_sp/128, op->stats.maxsp); /* causes Pow/16 sp/tick */
374     op->last_sp%=128;
375     }
376    
377     /* this should probably get modified by many more values.
378     * (eg, creatures resistance to fear, level, etc. )
379     */
380     if(QUERY_FLAG(op, FLAG_SCARED) &&!(RANDOM()%20)) {
381     CLEAR_FLAG(op,FLAG_SCARED); /* Time to regain some "guts"... */
382     }
383    
384 root 1.2 if (execute_event (op, EVENT_MOVE, op->enemy, 0, 0, SCRIPT_FIX_ALL))
385     return 0;
386    
387 root 1.1 /* If we don't have an enemy, do special movement or the like */
388     if(!enemy) {
389     if(QUERY_FLAG(op, FLAG_ONLY_ATTACK)) {
390     remove_ob(op);
391     free_object(op);
392     return 1;
393     }
394    
395     /* Probably really a bug for a creature to have both
396     * stand still and a movement type set.
397     */
398     if(!QUERY_FLAG(op, FLAG_STAND_STILL)) {
399     if (op->attack_movement & HI4)
400     {
401     switch (op->attack_movement & HI4) {
402     case (PETMOVE):
403     pet_move (op);
404     break;
405    
406     case (CIRCLE1):
407     circ1_move (op);
408     break;
409    
410     case (CIRCLE2):
411     circ2_move (op);
412     break;
413    
414     case (PACEV):
415     pace_movev(op);
416     break;
417    
418     case (PACEH):
419     pace_moveh(op);
420     break;
421    
422     case (PACEV2):
423     pace2_movev (op);
424     break;
425    
426     case (PACEH2):
427     pace2_moveh (op);
428     break;
429    
430     case (RANDO):
431     rand_move (op);
432     break;
433    
434     case (RANDO2):
435     move_randomly (op);
436     break;
437     }
438     return 0;
439     }
440     else if (QUERY_FLAG(op,FLAG_RANDOM_MOVE))
441     (void) move_randomly(op);
442    
443     } /* stand still */
444     return 0;
445     } /* no enemy */
446    
447     /* We have an enemy. Block immediately below is for pets */
448     if((op->attack_movement&HI4) == PETMOVE && (owner = get_owner(op)) != NULL && !on_same_map(op,owner))
449     {
450     follow_owner(op, owner);
451     /* If the pet was unable to follow the owner, free it */
452     if(QUERY_FLAG(op, FLAG_REMOVED) && FABS(op->speed) > MIN_ACTIVE_SPEED) {
453     remove_friendly_object(op);
454     free_object(op);
455     return 1;
456     }
457     return 0;
458     }
459    
460     /* doppleganger code to change monster facing to that of the nearest
461     * player. Hmm. The code is here, but no monster in the current
462     * arch set uses it.
463     */
464     if ( (op->race != NULL)&& strcmp(op->race,"doppleganger") == 0)
465     {
466     op->face = enemy->face;
467     if (op->name)
468     free_string(op->name);
469     add_refcount(op->name = enemy->name);
470     }
471    
472     /* Calculate range information for closest body part - this
473     * is used for the 'skill' code, which isn't that smart when
474     * it comes to figuring it out - otherwise, giants throw boulders
475     * into themselves.
476     */
477     get_rangevector(op, enemy, &rv, 0);
478    
479     /* Move the check for scared up here - if the monster was scared,
480     * we were not doing any of the logic below, so might as well save
481     * a few cpu cycles.
482     */
483     if (!QUERY_FLAG(op, FLAG_SCARED))
484     {
485     rv_vector rv1;
486    
487     /* now we test every part of an object .... this is a real ugly piece of code */
488     for (part=op; part!=NULL; part=part->more) {
489     get_rangevector(part, enemy, &rv1, 0x1);
490     dir=rv1.direction;
491    
492     /* hm, not sure about this part - in original was a scared flag here too
493     * but that we test above... so can be old code here
494     */
495     if(QUERY_FLAG(op,FLAG_RUN_AWAY))
496     dir=absdir(dir+4);
497     if(QUERY_FLAG(op,FLAG_CONFUSED))
498     dir = absdir(dir + RANDOM()%3 + RANDOM()%3 - 2);
499    
500     if(QUERY_FLAG(op,FLAG_CAST_SPELL) && !(RANDOM()%3)) {
501     if(monster_cast_spell(op,part,enemy,dir,&rv1))
502     return 0;
503     }
504    
505     if(QUERY_FLAG(op,FLAG_READY_SCROLL) && !(RANDOM()%3)) {
506     if(monster_use_scroll(op,part,enemy,dir,&rv1))
507     return 0;
508     }
509    
510     if(QUERY_FLAG(op,FLAG_READY_RANGE)&&!(RANDOM()%3)) {
511     if(monster_use_range(op,part,enemy,dir))
512     return 0;
513     }
514     if(QUERY_FLAG(op,FLAG_READY_SKILL)&&!(RANDOM()%3)) {
515     if(monster_use_skill(op,rv.part,enemy,rv.direction))
516     return 0;
517     }
518     if(QUERY_FLAG(op,FLAG_READY_BOW)&&!(RANDOM()%2)) {
519     if(monster_use_bow(op,part,enemy,dir))
520     return 0;
521     }
522     } /* for processing of all parts */
523     } /* If not scared */
524    
525    
526     part = rv.part;
527     dir=rv.direction;
528    
529     if(QUERY_FLAG(op, FLAG_SCARED) || QUERY_FLAG(op,FLAG_RUN_AWAY))
530     dir=absdir(dir+4);
531    
532     if(QUERY_FLAG(op,FLAG_CONFUSED))
533     dir = absdir(dir + RANDOM()%3 + RANDOM()%3 - 2);
534    
535     if ((op->attack_movement & LO4) && !QUERY_FLAG(op, FLAG_SCARED))
536     {
537     switch (op->attack_movement & LO4) {
538     case DISTATT:
539     dir = dist_att (dir,op,enemy,part,&rv);
540     break;
541    
542     case RUNATT:
543     dir = run_att (dir,op,enemy,part,&rv);
544     break;
545    
546     case HITRUN:
547     dir = hitrun_att(dir,op,enemy);
548     break;
549    
550     case WAITATT:
551     dir = wait_att (dir,op,enemy,part,&rv);
552     break;
553    
554     case RUSH: /* default - monster normally moves towards player */
555     case ALLRUN:
556     break;
557    
558     case DISTHIT:
559     dir = disthit_att (dir,op,enemy,part,&rv);
560     break;
561    
562     case WAIT2:
563     dir = wait_att2 (dir,op,enemy,part,&rv);
564     break;
565    
566     default:
567     LOG(llevDebug,"Illegal low mon-move: %d\n",op->attack_movement & LO4);
568     }
569     }
570    
571     if (!dir)
572     return 0;
573    
574     if (!QUERY_FLAG(op,FLAG_STAND_STILL)) {
575     if(move_object(op,dir)) /* Can the monster move directly toward player? */
576     return 0;
577    
578     if(QUERY_FLAG(op, FLAG_SCARED) || !can_hit(part,enemy,&rv)
579     || QUERY_FLAG(op,FLAG_RUN_AWAY)) {
580    
581     /* Try move around corners if !close */
582     int maxdiff = (QUERY_FLAG(op, FLAG_ONLY_ATTACK) || RANDOM()&1) ? 1 : 2;
583     for(diff = 1; diff <= maxdiff; diff++) {
584     /* try different detours */
585     int m = 1-(RANDOM()&2); /* Try left or right first? */
586     if(move_object(op,absdir(dir + diff*m)) ||
587     move_object(op,absdir(dir - diff*m)))
588     return 0;
589     }
590     }
591     } /* if monster is not standing still */
592    
593     /*
594     * Eneq(@csd.uu.se): Patch to make RUN_AWAY or SCARED monsters move a random
595     * direction if they can't move away.
596     */
597     if (!QUERY_FLAG(op, FLAG_ONLY_ATTACK)&&(QUERY_FLAG(op,FLAG_RUN_AWAY)||QUERY_FLAG(op, FLAG_SCARED)))
598     if(move_randomly(op))
599     return 0;
600    
601     /*
602     * Try giving the monster a new enemy - the player that is closest
603     * to it. In this way, it won't just keep trying to get to a target
604     * that is inaccessible.
605     * This could be more clever - it should go through a list of several
606     * enemies, as it is now, you could perhaps get situations where there
607     * are two players flanking the monster at close distance, but which
608     * the monster can't get to, and a third one at a far distance that
609     * the monster could get to - as it is, the monster won't look at that
610     * third one.
611     */
612     if (!QUERY_FLAG(op, FLAG_FRIENDLY) && enemy == op->enemy)
613     {
614     object *nearest_player = get_nearest_player(op);
615     if (nearest_player && nearest_player != enemy && !can_hit(part,enemy,&rv)) {
616     op->enemy = NULL;
617     enemy = nearest_player;
618     }
619     }
620    
621     if(!QUERY_FLAG(op, FLAG_SCARED)&&can_hit(part,enemy,&rv))
622     {
623     /* The adjustement to wc that was here before looked totally bogus -
624     * since wc can in fact get negative, that would mean by adding
625     * the current wc, the creature gets better? Instead, just
626     * add a fixed amount - nasty creatures that are runny away should
627     * still be pretty nasty.
628     */
629     if(QUERY_FLAG(op,FLAG_RUN_AWAY))
630     {
631     part->stats.wc+=10;
632     (void)skill_attack(enemy,part,0,NULL, NULL);
633     part->stats.wc-=10;
634     }
635     else
636     (void)skill_attack(enemy,part,0,NULL, NULL);
637     } /* if monster is in attack range */
638    
639     if(QUERY_FLAG(part,FLAG_FREED)) /* Might be freed by ghost-attack or hit-back */
640     return 1;
641    
642     if(QUERY_FLAG(op, FLAG_ONLY_ATTACK))
643     {
644     remove_ob(op);
645     free_object(op);
646     return 1;
647     }
648     return 0;
649     }
650     int can_hit(object *ob1,object *ob2, rv_vector *rv) {
651     object *more;
652     rv_vector rv1;
653    
654     if(QUERY_FLAG(ob1,FLAG_CONFUSED)&&!(RANDOM()%3))
655     return 0;
656    
657     if (abs(rv->distance_x)<2&&abs(rv->distance_y)<2) return 1;
658    
659     /* check all the parts of ob2 - just because we can't get to
660     * its head doesn't mean we don't want to pound its feet
661     */
662     for (more = ob2->more; more!=NULL; more = more->more) {
663     get_rangevector(ob1, more, &rv1, 0);
664     if (abs(rv1.distance_x)<2&&abs(rv1.distance_y)<2) return 1;
665     }
666     return 0;
667    
668     }
669    
670     /* Returns 1 is monster should cast spell sp at an enemy
671     * Returns 0 if the monster should not cast this spell.
672     *
673     * Note that this function does not check to see if the monster can
674     * in fact cast the spell (sp dependencies and what not.) That is because
675     * this function is also sued to see if the monster should use spell items
676     * (rod/horn/wand/scroll).
677     * Note that there are certainly other offensive spells that could be
678     * included, but I decided to leave out the spells that may kill more
679     * monsters than players (eg, disease).
680     *
681     * This could be a lot smarter - if there are few monsters around,
682     * then disease might not be as bad. Likewise, if the monster is damaged,
683     * the right type of healing spell could be useful.
684     */
685    
686     static int monster_should_cast_spell(object *monster, object *spell_ob)
687     {
688     if (spell_ob->subtype == SP_BOLT || spell_ob->subtype == SP_BULLET ||
689     spell_ob->subtype == SP_EXPLOSION || spell_ob->subtype == SP_CONE ||
690     spell_ob->subtype == SP_BOMB || spell_ob->subtype == SP_SMITE ||
691     spell_ob->subtype == SP_MAGIC_MISSILE || spell_ob->subtype == SP_SUMMON_GOLEM ||
692     spell_ob->subtype == SP_MAGIC_WALL || spell_ob->subtype == SP_SUMMON_MONSTER ||
693     spell_ob->subtype == SP_MOVING_BALL || spell_ob->subtype == SP_SWARM ||
694     spell_ob->subtype == SP_INVISIBLE)
695    
696     return 1;
697    
698     return 0;
699     }
700    
701    
702     #define MAX_KNOWN_SPELLS 20
703    
704     /* Returns a randomly selected spell. This logic is still
705     * less than ideal. This code also only seems to deal with
706     * wizard spells, as the check is against sp, and not grace.
707     * can mosnters know cleric spells?
708     */
709     object *monster_choose_random_spell(object *monster) {
710     object *altern[MAX_KNOWN_SPELLS];
711     object *tmp;
712     int i=0;
713    
714     for(tmp=monster->inv;tmp!=NULL;tmp=tmp->below)
715     if (tmp->type==SPELLBOOK || tmp->type==SPELL) {
716     /* Check and see if it's actually a useful spell.
717     * If its a spellbook, the spell is actually the inventory item.
718     * if it is a spell, then it is just the object itself.
719     */
720     if (monster_should_cast_spell(monster, (tmp->type==SPELLBOOK)?tmp->inv:tmp)) {
721     altern[i++]=tmp;
722     if(i==MAX_KNOWN_SPELLS)
723     break;
724     }
725     }
726     if(!i)
727     return NULL;
728     return altern[RANDOM()%i];
729     }
730    
731     /* This checks to see if the monster should cast a spell/ability.
732     * it returns true if the monster casts a spell, 0 if he doesn't.
733     * head is the head of the monster.
734     * part is the part of the monster we are checking against.
735     * pl is the target.
736     * dir is the direction to case.
737     * rv is the vector which describes where the enemy is.
738     */
739    
740     int monster_cast_spell(object *head, object *part,object *pl,int dir, rv_vector *rv) {
741     object *spell_item;
742     object *owner;
743     rv_vector rv1;
744    
745     /* If you want monsters to cast spells over friends, this spell should
746     * be removed. It probably should be in most cases, since monsters still
747     * don't care about residual effects (ie, casting a cone which may have a
748     * clear path to the player, the side aspects of the code will still hit
749     * other monsters)
750     */
751     if(!(dir=path_to_player(part,pl,0)))
752     return 0;
753    
754     if(QUERY_FLAG(head,FLAG_FRIENDLY) && (owner = get_owner(head)) != NULL) {
755     get_rangevector(head, owner, &rv1, 0x1);
756     if(dirdiff(dir,rv1.direction) < 2) {
757     return 0; /* Might hit owner with spell */
758     }
759     }
760    
761     if(QUERY_FLAG(head,FLAG_CONFUSED))
762     dir = absdir(dir + RANDOM()%3 + RANDOM()%3 - 2);
763    
764     /* If the monster hasn't already chosen a spell, choose one
765     * I'm not sure if it really make sense to pre-select spells (events
766     * could be different by the time the monster goes again).
767     */
768     if(head->spellitem==NULL) {
769     if((spell_item=monster_choose_random_spell(head))==NULL) {
770     LOG(llevMonster,"Turned off spells in %s\n",head->name);
771     CLEAR_FLAG(head, FLAG_CAST_SPELL); /* Will be turned on when picking up book */
772     return 0;
773     }
774     if (spell_item->type == SPELLBOOK) {
775     if (!spell_item->inv) {
776     LOG(llevError,"spellbook %s does not contain a spell?\n", spell_item->name);
777     return 0;
778     }
779     spell_item=spell_item->inv;
780     }
781     }
782     else
783     spell_item=head->spellitem;
784    
785     if (!spell_item) return 0;
786    
787     /* Best guess this is a defensive/healing spell */
788     if (spell_item->range<=1 || spell_item->stats.dam < 0)
789     dir = 0;
790    
791     /* Monster doesn't have enough spell-points */
792     if(head->stats.sp<SP_level_spellpoint_cost(head,spell_item, SPELL_MANA))
793     return 0;
794    
795     if(head->stats.grace<SP_level_spellpoint_cost(head,spell_item, SPELL_GRACE))
796     return 0;
797    
798     head->stats.sp-=SP_level_spellpoint_cost(head,spell_item, SPELL_MANA);
799     head->stats.grace-=SP_level_spellpoint_cost(head,spell_item, SPELL_GRACE);
800    
801     /* set this to null, so next time monster will choose something different */
802     head->spellitem = NULL;
803    
804     return cast_spell(part,part,dir, spell_item, NULL);
805     }
806    
807    
808     int monster_use_scroll(object *head, object *part,object *pl,int dir, rv_vector *rv) {
809     object *scroll;
810     object *owner;
811     rv_vector rv1;
812    
813     /* If you want monsters to cast spells over friends, this spell should
814     * be removed. It probably should be in most cases, since monsters still
815     * don't care about residual effects (ie, casting a cone which may have a
816     * clear path to the player, the side aspects of the code will still hit
817     * other monsters)
818     */
819     if(!(dir=path_to_player(part,pl,0)))
820     return 0;
821    
822     if(QUERY_FLAG(head,FLAG_FRIENDLY) && (owner = get_owner(head)) != NULL) {
823     get_rangevector(head, owner, &rv1, 0x1);
824     if(dirdiff(dir,rv1.direction) < 2) {
825     return 0; /* Might hit owner with spell */
826     }
827     }
828    
829     if(QUERY_FLAG(head,FLAG_CONFUSED))
830     dir = absdir(dir + RANDOM()%3 + RANDOM()%3 - 2);
831    
832     for (scroll=head->inv; scroll; scroll=scroll->below)
833     if (scroll->type == SCROLL && monster_should_cast_spell(head, scroll->inv)) break;
834    
835     /* Used up all his scrolls, so nothing do to */
836     if (!scroll) {
837     CLEAR_FLAG(head, FLAG_READY_SCROLL);
838     return 0;
839     }
840    
841     /* Spell should be cast on caster (ie, heal, strength) */
842     if (scroll->inv->range==0)
843     dir = 0;
844    
845     apply_scroll(part, scroll, dir);
846     return 1;
847     }
848    
849     /* monster_use_skill()-implemented 95-04-28 to allow monster skill use.
850     * Note that monsters do not need the skills SK_MELEE_WEAPON and
851     * SK_MISSILE_WEAPON to make those respective attacks, if we
852     * required that we would drastically increase the memory
853     * requirements of CF!!
854     *
855     * The skills we are treating here are all but those. -b.t.
856     *
857     * At the moment this is only useful for throwing, perhaps for
858     * stealing. TODO: This should be more integrated in the game. -MT, 25.11.01
859     */
860    
861     int monster_use_skill(object *head, object *part, object *pl,int dir) {
862     object *skill, *owner;
863    
864     if(!(dir=path_to_player(part,pl,0)))
865     return 0;
866    
867     if(QUERY_FLAG(head,FLAG_FRIENDLY) && (owner = get_owner(head)) != NULL) {
868     int dir2 = find_dir_2(head->x-owner->x, head->y-owner->y);
869     if(dirdiff(dir,dir2) < 1)
870     return 0; /* Might hit owner with skill -thrown rocks for example ?*/
871     }
872     if(QUERY_FLAG(head,FLAG_CONFUSED))
873     dir = absdir(dir + RANDOM()%3 + RANDOM()%3 - 2);
874    
875     /* skill selection - monster will use the next unused skill.
876     * well...the following scenario will allow the monster to
877     * toggle between 2 skills. One day it would be nice to make
878     * more skills available to monsters.
879     */
880    
881     for(skill=head->inv;skill!=NULL;skill=skill->below)
882     if(skill->type==SKILL && skill!=head->chosen_skill) {
883     head->chosen_skill=skill;
884     break;
885     }
886    
887     if(!skill && !head->chosen_skill) {
888     LOG(llevDebug,"Error: Monster %s (%d) has FLAG_READY_SKILL without skill.\n",
889     head->name,head->count);
890     CLEAR_FLAG(head, FLAG_READY_SKILL);
891     return 0;
892     }
893     /* use skill */
894     return do_skill(head, part, head->chosen_skill,dir,NULL);
895     }
896    
897     /* Monster will use a ranged spell attack. */
898    
899     int monster_use_range(object *head,object *part,object *pl,int dir)
900     {
901     object *wand, *owner;
902     int at_least_one = 0;
903    
904     if(!(dir=path_to_player(part,pl,0)))
905     return 0;
906    
907     if(QUERY_FLAG(head,FLAG_FRIENDLY) && (owner = get_owner(head)) != NULL) {
908     int dir2 = find_dir_2(head->x-owner->x, head->y-owner->y);
909     if(dirdiff(dir,dir2) < 2)
910     return 0; /* Might hit owner with spell */
911     }
912     if(QUERY_FLAG(head,FLAG_CONFUSED))
913     dir = absdir(dir + RANDOM()%3 + RANDOM()%3 - 2);
914    
915     for(wand=head->inv;wand!=NULL;wand=wand->below)
916     {
917     if (wand->type == WAND)
918     {
919     /* Found a wand, let's see if it has charges left */
920     at_least_one = 1;
921     if( wand->stats.food<=0 )
922     continue;
923    
924     cast_spell( head, wand, dir, wand->inv, NULL );
925    
926     if ( !( --wand->stats.food ) )
927     {
928     if ( wand->arch )
929     {
930     CLEAR_FLAG(wand, FLAG_ANIMATE);
931     wand->face = wand->arch->clone.face;
932     wand->speed = 0;
933     update_ob_speed(wand);
934     }
935     }
936     /* Success */
937     return 1;
938     }
939     else if ( wand->type == ROD || wand->type==HORN ) {
940     /* Found rod/horn, let's use it if possible */
941     at_least_one = 1;
942     if( wand->stats.hp < MAX( wand->inv->stats.sp, wand->inv->stats.grace ) )
943     continue;
944    
945     /* drain charge before casting spell - can be a case where the
946     * spell destroys the monster, and rod, so if done after, results
947     * in crash.
948     */
949     drain_rod_charge( wand );
950     cast_spell( head, wand, dir, wand->inv, NULL );
951    
952     /* Success */
953     return 1;
954     }
955     }
956    
957     if ( at_least_one )
958     return 0;
959    
960     LOG(llevError,"Error: Monster %s (%d) HAS_READY_RANG() without wand/horn/rod.\n",
961     head->name,head->count);
962     CLEAR_FLAG(head, FLAG_READY_RANGE);
963     return 0;
964     }
965    
966     int monster_use_bow(object *head, object *part, object *pl, int dir) {
967     object *owner;
968    
969     if(!(dir=path_to_player(part,pl,0)))
970     return 0;
971     if(QUERY_FLAG(head,FLAG_CONFUSED))
972     dir = absdir(dir + RANDOM()%3 + RANDOM()%3 - 2);
973    
974     if(QUERY_FLAG(head,FLAG_FRIENDLY) && (owner = get_owner(head)) != NULL) {
975     int dir2 = find_dir_2(head->x-owner->x, head->y-owner->y);
976     if(dirdiff(dir,dir2) < 1)
977     return 0; /* Might hit owner with arrow */
978     }
979    
980     /* in server/player.c */
981     return fire_bow(head, part, NULL, dir, 0, part->x, part->y);
982    
983     }
984    
985     /* Checks if putting on 'item' will make 'who' do more
986     * damage. This is a very simplistic check - also checking things
987     * like speed and ac are also relevant.
988     *
989     * return true if item is a better object.
990     */
991    
992     int check_good_weapon(object *who, object *item) {
993     object *other_weap;
994     int val=0, i;
995    
996     for(other_weap=who->inv;other_weap!=NULL;other_weap=other_weap->below)
997     if(other_weap->type==item->type&&QUERY_FLAG(other_weap,FLAG_APPLIED))
998     break;
999    
1000     if(other_weap==NULL) /* No other weapons */
1001     return 1;
1002    
1003     /* Rather than go through and apply the new one, and see if it is
1004     * better, just do some simple checks
1005     * Put some multipliers for things that hvae several effects,
1006     * eg, magic affects both damage and wc, so it has more weight
1007     */
1008    
1009     val = item->stats.dam - other_weap->stats.dam;
1010     val += (item->magic - other_weap->magic) * 3;
1011     /* Monsters don't really get benefits from things like regen rates
1012     * from items. But the bonus for their stats are very important.
1013     */
1014     for (i=0; i<NUM_STATS; i++)
1015     val += (get_attr_value(&item->stats, i) - get_attr_value(&other_weap->stats, i))*2;
1016    
1017     if (val > 0) return 1;
1018     else return 0;
1019    
1020     }
1021    
1022     int check_good_armour(object *who, object *item) {
1023     object *other_armour;
1024     int val=0,i;
1025    
1026     for (other_armour = who->inv; other_armour != NULL;
1027     other_armour = other_armour->below)
1028     if (other_armour->type == item->type && QUERY_FLAG(other_armour,FLAG_APPLIED))
1029     break;
1030    
1031     if (other_armour == NULL) /* No other armour, use the new */
1032     return 1;
1033    
1034     /* Like above function , see which is better */
1035     val = item->stats.ac - other_armour->stats.ac;
1036     val = (item->resist[ATNR_PHYSICAL] - other_armour->resist[ATNR_PHYSICAL])/5;
1037     val += (item->magic - other_armour->magic) * 3;
1038    
1039     /* for the other protections, do weigh them very much in the equation -
1040     * it is the armor protection which is most important, because there is
1041     * no good way to know what the player may attack the monster with.
1042     * So if the new item has better protection than the old, give that higher
1043     * value. If the reverse, then decrease the value of this item some.
1044     */
1045     for (i=1; i <NROFATTACKS; i++) {
1046     if (item->resist[i] > other_armour->resist[i]) val++;
1047     else if (item->resist[i] < other_armour->resist[i]) val--;
1048     }
1049    
1050     /* Very few armours have stats, so not much need to worry about those. */
1051    
1052     if (val > 0) return 1;
1053     else return 0;
1054    
1055     }
1056    
1057     /*
1058     * monster_check_pickup(): checks for items that monster can pick up.
1059     *
1060     * Vick's (vick@bern.docs.uu.se) fix 921030 for the sweeper blob.
1061     * Each time the blob passes over some treasure, it will
1062     * grab it a.s.a.p.
1063     *
1064     * Eneq(@csd.uu.se): This can now be defined in the archetypes, added code
1065     * to handle this.
1066     *
1067     * This function was seen be continueing looping at one point (tmp->below
1068     * became a recursive loop. It may be better to call monster_check_apply
1069     * after we pick everything up, since that function may call others which
1070     * affect stacking on this space.
1071     */
1072    
1073     void monster_check_pickup(object *monster) {
1074     object *tmp,*next;
1075     int next_tag;
1076    
1077     for(tmp=monster->below;tmp!=NULL;tmp=next) {
1078     next=tmp->below;
1079     next_tag = next ? next->count : 0;
1080     if (monster_can_pick(monster,tmp)) {
1081     remove_ob(tmp);
1082     tmp = insert_ob_in_ob(tmp,monster);
1083     (void) monster_check_apply(monster,tmp);
1084     }
1085     /* We could try to re-establish the cycling, of the space, but probably
1086     * not a big deal to just bail out.
1087     */
1088     if (next && was_destroyed(next, next_tag)) return;
1089     }
1090     }
1091    
1092     /*
1093     * monster_can_pick(): If the monster is interested in picking up
1094     * the item, then return 0. Otherwise 0.
1095     * Instead of pick_up, flags for "greed", etc, should be used.
1096     * I've already utilized flags for bows, wands, rings, etc, etc. -Frank.
1097     */
1098    
1099     int monster_can_pick(object *monster, object *item) {
1100     int flag=0;
1101     int i;
1102    
1103     if(!can_pick(monster,item))
1104     return 0;
1105    
1106     if(QUERY_FLAG(item,FLAG_UNPAID))
1107     return 0;
1108    
1109     if (monster->pick_up&64) /* All */
1110     flag=1;
1111    
1112     else switch(item->type) {
1113     case MONEY:
1114     case GEM:
1115     flag=monster->pick_up&2;
1116     break;
1117    
1118     case FOOD:
1119     flag=monster->pick_up&4;
1120     break;
1121    
1122     case WEAPON:
1123     flag=(monster->pick_up&8)||QUERY_FLAG(monster,FLAG_USE_WEAPON);
1124     break;
1125    
1126     case ARMOUR:
1127     case SHIELD:
1128     case HELMET:
1129     case BOOTS:
1130     case GLOVES:
1131     case GIRDLE:
1132     flag=(monster->pick_up&16)||QUERY_FLAG(monster,FLAG_USE_ARMOUR);
1133     break;
1134    
1135     case SKILL:
1136     flag=QUERY_FLAG(monster,FLAG_CAN_USE_SKILL);
1137     break;
1138    
1139     case RING:
1140     flag=QUERY_FLAG(monster,FLAG_USE_RING);
1141     break;
1142    
1143     case WAND:
1144     case HORN:
1145     case ROD:
1146     flag=QUERY_FLAG(monster,FLAG_USE_RANGE);
1147     break;
1148    
1149     case SPELLBOOK:
1150     flag=(monster->arch!=NULL&&QUERY_FLAG((&monster->arch->clone),FLAG_CAST_SPELL));
1151     break;
1152    
1153     case SCROLL:
1154     flag = QUERY_FLAG(monster,FLAG_USE_SCROLL);
1155     break;
1156    
1157     case BOW:
1158     case ARROW:
1159     flag=QUERY_FLAG(monster,FLAG_USE_BOW);
1160     break;
1161     }
1162     /* Simplistic check - if the monster has a location to equip it, he will
1163     * pick it up. Note that this doesn't handle cases where an item may
1164     * use several locations.
1165     */
1166     for (i=0; i < NUM_BODY_LOCATIONS; i++) {
1167     if (monster->body_info[i] && item->body_info[i]) {
1168     flag=1;
1169     break;
1170     }
1171     }
1172    
1173     if (((!(monster->pick_up&32))&&flag) || ((monster->pick_up&32)&&(!flag)))
1174     return 1;
1175     return 0;
1176     }
1177    
1178     /*
1179     * monster_apply_below():
1180     * Vick's (vick@bern.docs.uu.se) @921107 -> If a monster who's
1181     * eager to apply things, encounters something apply-able,
1182     * then make him apply it
1183     */
1184    
1185     void monster_apply_below(object *monster) {
1186     object *tmp, *next;
1187    
1188     for(tmp=monster->below;tmp!=NULL;tmp=next) {
1189     next=tmp->below;
1190     switch (tmp->type) {
1191     case CF_HANDLE:
1192     case TRIGGER:
1193     if (monster->will_apply&1)
1194     manual_apply(monster,tmp,0);
1195     break;
1196    
1197     case TREASURE:
1198     if (monster->will_apply&2)
1199     manual_apply(monster,tmp,0);
1200     break;
1201    
1202     }
1203     if (QUERY_FLAG (tmp, FLAG_IS_FLOOR))
1204     break;
1205     }
1206     }
1207    
1208     /*
1209     * monster_check_apply() is meant to be called after an item is
1210     * inserted in a monster.
1211     * If an item becomes outdated (monster found a better item),
1212     * a pointer to that object is returned, so it can be dropped.
1213     * (so that other monsters can pick it up and use it)
1214     * Note that as things are now, monsters never drop something -
1215     * they can pick up all that they can use.
1216     */
1217    
1218     /* Sept 96, fixed this so skills will be readied -b.t.*/
1219    
1220     void monster_check_apply(object *mon, object *item) {
1221    
1222     int flag = 0;
1223    
1224     if(item->type==SPELLBOOK&&
1225     mon->arch!=NULL&&(QUERY_FLAG((&mon->arch->clone),FLAG_CAST_SPELL))) {
1226     SET_FLAG(mon, FLAG_CAST_SPELL);
1227     return;
1228     }
1229    
1230     /* If for some reason, this item is already applied, no more work to do */
1231     if(QUERY_FLAG(item,FLAG_APPLIED)) return;
1232    
1233     /* Might be better not to do this - if the monster can fire a bow,
1234     * it is possible in his wanderings, he will find one to use. In
1235     * which case, it would be nice to have ammo for it.
1236     */
1237     if(QUERY_FLAG(mon,FLAG_USE_BOW) && item->type==ARROW) {
1238     /* Check for the right kind of bow */
1239     object *bow;
1240     for(bow=mon->inv;bow!=NULL;bow=bow->below)
1241     if(bow->type==BOW && bow->race==item->race) {
1242     SET_FLAG(mon, FLAG_READY_BOW);
1243     LOG(llevMonster,"Found correct bow for arrows.\n");
1244     return; /* nothing more to do for arrows */
1245     }
1246     }
1247    
1248     if (item->type == TREASURE && mon->will_apply & WILL_APPLY_TREASURE) flag=1;
1249     /* Eating food gets hp back */
1250     else if (item->type == FOOD && mon->will_apply & WILL_APPLY_FOOD) flag=1;
1251     else if (item->type == SCROLL && QUERY_FLAG(mon, FLAG_USE_SCROLL)) {
1252 root 1.3 if (item->inv && monster_should_cast_spell(mon, item->inv))
1253 root 1.1 SET_FLAG(mon, FLAG_READY_SCROLL);
1254     /* Don't use it right now */
1255     return;
1256     }
1257     else if (item->type == WEAPON) flag = check_good_weapon(mon,item);
1258     else if (IS_ARMOR(item)) flag = check_good_armour(mon,item);
1259     /* Should do something more, like make sure this is a better item */
1260     else if (item->type == RING)
1261     flag=1;
1262     else if ( item->type==WAND || item->type == ROD || item->type==HORN )
1263     {
1264     /* We never really 'ready' the wand/rod/horn, because that would mean the
1265     * weapon would get undone.
1266     */
1267     if (!(can_apply_object(mon, item) & CAN_APPLY_NOT_MASK))
1268     {
1269     SET_FLAG(mon, FLAG_READY_RANGE);
1270     SET_FLAG(item, FLAG_APPLIED);
1271     }
1272     return;
1273     }
1274     else if (item->type == BOW) {
1275     /* We never really 'ready' the bow, because that would mean the
1276     * weapon would get undone.
1277     */
1278     if (!(can_apply_object(mon, item) & CAN_APPLY_NOT_MASK))
1279     SET_FLAG(mon, FLAG_READY_BOW);
1280     return;
1281     }
1282     else if ( item->type == SKILL )
1283     {
1284     /*
1285     * skills are specials: monsters must have the 'FLAG_READY_SKILL' flag set,
1286     * else they can't use the skill...
1287     * Skills also don't need to get applied, so return now.
1288     */
1289     SET_FLAG(mon, FLAG_READY_SKILL);
1290     return;
1291     }
1292    
1293    
1294     /* if we don't match one of the above types, return now.
1295     * can_apply_object will say that we can apply things like flesh,
1296     * bolts, and whatever else, because it only checks against the
1297     * body_info locations.
1298     */
1299     if (!flag) return;
1300    
1301     /* Check to see if the monster can use this item. If not, no need
1302     * to do further processing. Note that can_apply_object already checks
1303     * for the CAN_USE flags.
1304     */
1305     if (can_apply_object(mon, item) & CAN_APPLY_NOT_MASK) return;
1306    
1307     /* should only be applying this item, not unapplying it.
1308     * also, ignore status of curse so they can take off old armour.
1309     * monsters have some advantages after all.
1310     */
1311     manual_apply(mon, item, AP_APPLY | AP_IGNORE_CURSE);
1312    
1313     return;
1314     }
1315    
1316     void npc_call_help(object *op) {
1317     int x,y, mflags;
1318     object *npc;
1319     sint16 sx, sy;
1320     mapstruct *m;
1321    
1322     for(x = -3; x < 4; x++)
1323     for(y = -3; y < 4; y++) {
1324     m = op->map;
1325     sx = op->x + x;
1326     sy = op->y + y;
1327     mflags = get_map_flags(m, &m, sx, sy, &sx, &sy);
1328     /* If nothing alive on this space, no need to search the space. */
1329     if ((mflags & P_OUT_OF_MAP) || !(mflags & P_IS_ALIVE))
1330     continue;
1331    
1332     for(npc = get_map_ob(m,sx,sy);npc!=NULL;npc=npc->above)
1333     if(QUERY_FLAG(npc, FLAG_ALIVE)&&QUERY_FLAG(npc, FLAG_UNAGGRESSIVE))
1334     npc->enemy = op->enemy;
1335     }
1336     }
1337    
1338    
1339     int dist_att (int dir , object *ob, object *enemy, object *part, rv_vector *rv) {
1340    
1341     if (can_hit(part,enemy,rv))
1342     return dir;
1343     if (rv->distance < 10)
1344     return absdir(dir+4);
1345     else if (rv->distance>18)
1346     return dir;
1347     return 0;
1348     }
1349    
1350     int run_att (int dir, object *ob, object *enemy,object *part, rv_vector *rv) {
1351    
1352     if ((can_hit (part,enemy,rv) && ob->move_status <20) || ob->move_status <20) {
1353     ob->move_status++;
1354     return (dir);
1355     }
1356     else if (ob->move_status >20)
1357     ob->move_status = 0;
1358     return absdir (dir+4);
1359     }
1360    
1361     int hitrun_att (int dir, object *ob,object *enemy) {
1362     if (ob->move_status ++ < 25)
1363     return dir;
1364     else if (ob->move_status <50)
1365     return absdir (dir+4);
1366     else
1367     ob->move_status = 0;
1368     return absdir(dir+4);
1369     }
1370    
1371     int wait_att (int dir, object *ob,object *enemy,object *part,rv_vector *rv) {
1372    
1373     int inrange = can_hit (part, enemy,rv);
1374    
1375     if (ob->move_status || inrange)
1376     ob->move_status++;
1377    
1378     if (ob->move_status == 0)
1379     return 0;
1380     else if (ob->move_status <10)
1381     return dir;
1382     else if (ob->move_status <15)
1383     return absdir(dir+4);
1384     ob->move_status = 0;
1385     return 0;
1386     }
1387    
1388     int disthit_att (int dir, object *ob, object *enemy, object *part,rv_vector *rv) {
1389    
1390     /* The logic below here looked plain wrong before. Basically, what should
1391     * happen is that if the creatures hp percentage falls below run_away,
1392     * the creature should run away (dir+4)
1393     * I think its wrong for a creature to have a zero maxhp value, but
1394     * at least one map has this set, and whatever the map contains, the
1395     * server should try to be resilant enough to avoid the problem
1396     */
1397     if (ob->stats.maxhp && (ob->stats.hp*100)/ob->stats.maxhp < ob->run_away)
1398     return absdir(dir+4);
1399     return dist_att (dir,ob,enemy,part,rv);
1400     }
1401    
1402     int wait_att2 (int dir, object *ob,object *enemy,object *part, rv_vector *rv) {
1403     if (rv->distance < 9)
1404     return absdir (dir+4);
1405     return 0;
1406     }
1407    
1408     void circ1_move (object *ob) {
1409     static int circle [12] = {3,3,4,5,5,6,7,7,8,1,1,2};
1410     if(++ob->move_status > 11)
1411     ob->move_status = 0;
1412     if (!(move_object(ob,circle[ob->move_status])))
1413     (void) move_object(ob,RANDOM()%8+1);
1414     }
1415    
1416     void circ2_move (object *ob) {
1417     static int circle[20] = {3,3,3,4,4,5,5,5,6,6,7,7,7,8,8,1,1,1,2,2};
1418     if(++ob->move_status > 19)
1419     ob->move_status = 0;
1420     if(!(move_object(ob,circle[ob->move_status])))
1421     (void) move_object(ob,RANDOM()%8+1);
1422     }
1423    
1424     void pace_movev(object *ob) {
1425     if (ob->move_status++ > 6)
1426     ob->move_status = 0;
1427     if (ob->move_status < 4)
1428     (void) move_object (ob,5);
1429     else
1430     (void) move_object(ob,1);
1431     }
1432    
1433     void pace_moveh (object *ob) {
1434     if (ob->move_status++ > 6)
1435     ob->move_status = 0;
1436     if (ob->move_status < 4)
1437     (void) move_object(ob,3);
1438     else
1439     (void) move_object(ob,7);
1440     }
1441    
1442     void pace2_movev (object *ob) {
1443     if (ob->move_status ++ > 16)
1444     ob->move_status = 0;
1445     if (ob->move_status <6)
1446     (void) move_object (ob,5);
1447     else if (ob->move_status < 8)
1448     return;
1449     else if (ob->move_status <13)
1450     (void) move_object (ob,1);
1451     else return;
1452     }
1453    
1454     void pace2_moveh (object *ob) {
1455     if (ob->move_status ++ > 16)
1456     ob->move_status = 0;
1457     if (ob->move_status <6)
1458     (void) move_object (ob,3);
1459     else if (ob->move_status < 8)
1460     return;
1461     else if (ob->move_status <13)
1462     (void) move_object (ob,7);
1463     else return;
1464     }
1465    
1466     void rand_move (object *ob) {
1467     int i;
1468     if (ob->move_status <1 || ob->move_status >8 ||
1469     !(move_object(ob,ob->move_status|| ! (RANDOM()% 9))))
1470     for (i = 0; i < 5; i++)
1471     if (move_object(ob,ob->move_status = RANDOM()%8+1))
1472     return;
1473     }
1474    
1475     void check_earthwalls(object *op, mapstruct *m, int x, int y) {
1476     object *tmp;
1477     for (tmp = get_map_ob(m, x, y); tmp!=NULL; tmp=tmp->above) {
1478     if (tmp->type == EARTHWALL) {
1479     hit_player(tmp,op->stats.dam,op,AT_PHYSICAL,1);
1480     return;
1481     }
1482     }
1483     }
1484    
1485     void check_doors(object *op, mapstruct *m, int x, int y) {
1486     object *tmp;
1487     for (tmp = get_map_ob(m, x, y); tmp!=NULL; tmp=tmp->above) {
1488     if (tmp->type == DOOR) {
1489     hit_player(tmp,1000,op,AT_PHYSICAL,1);
1490     return;
1491     }
1492     }
1493     }
1494    
1495     /* This replaces all the msglang stuff about which seems to be a lot of
1496     * unneeded complication - since the setup of that data is never re-used
1497     * (say 'hi' to monster, then 'yes', it would re-do the entire parse-message)
1498     * it seems to me to make more sense to just have simple function that returns
1499     * the 'text' portion of the message that it matches - this savees us a bunch
1500     * of malloc's and free's, as well as that setup.
1501     * This function takes the message to be parsed in 'msg', the text to
1502     * match in 'match', and returns the portion of the message. This
1503     * returned portion is in a malloc'd buf that should be freed.
1504     * Returns NULL if no match is found.
1505     * The player is passed too, so that quest-related messages can be checked too.
1506     */
1507     static char *find_matching_message(object* pl, const char *msg, const char *match)
1508     {
1509     const char *cp=msg, *cp1, *cp2;
1510     char *cp3, regex[MAX_BUF], gotmatch=0;
1511    
1512     while (1) {
1513     if (strncmp(cp, "@match ", 7)) {
1514     LOG(llevDebug,"find_matching_message: Invalid message %s", msg);
1515     return NULL;
1516     }
1517     else {
1518     /* Find the end of the line, and copy the regex portion into it */
1519     cp2 = strchr(cp+7, '\n');
1520     strncpy(regex, cp+7, (cp2 - cp -7 ));
1521     regex[cp2 - cp -7] = 0;
1522    
1523     /* Find the next match command */
1524     cp1 = strstr(cp+6, "\n@match");
1525    
1526     /* Got a match - handle * as special case - proper regex would be .*,
1527     * but lots of messages don't use that form.
1528     */
1529     if (regex[0] == '*') gotmatch=1;
1530     else {
1531     char *pipe, *pnext=NULL;
1532     /* need to parse all the | seperators. Our re_cmp isn't
1533     * realy a fully blown regex parser.
1534     */
1535     for (pipe=regex; pipe != NULL; pipe = pnext) {
1536     pnext = strchr(pipe, '|');
1537     if (pnext) {
1538     *pnext = 0;
1539     pnext ++;
1540     }
1541     if (re_cmp(match, pipe)) {
1542     gotmatch = 1;
1543     break;
1544     }
1545     }
1546     }
1547     if (gotmatch) {
1548     if (cp1) {
1549     cp3 = malloc(cp1 - cp2 + 1);
1550     strncpy(cp3, cp2+1, cp1 - cp2);
1551     cp3[cp1 - cp2] = 0;
1552     }
1553     else { /* if no next match, just want the rest of the string */
1554     cp3 = strdup_local(cp2+1);
1555     }
1556     return cp3;
1557     }
1558     gotmatch = 0;
1559     if (cp1) cp = cp1 + 1;
1560     else return NULL;
1561     }
1562     }
1563     /* Should never get reached */
1564     }
1565    
1566     /* This function looks for an object or creature that is listening.
1567     * I've disabled the bit that has only the first npc monster listen -
1568     * we'll see how this works out. only the first npc listens, which
1569     * is sort of bogus since it uses the free_arr which has a preference
1570     * to certain directions.
1571     *
1572     * There is a rare even that the orig_map is used for - basically, if
1573     * a player says the magic word that gets him teleported off the map,
1574     * it can result in the new map putting the object count too high,
1575     * which forces the swap out of some other map. In some cases, the
1576     * map the player was just on now gets swapped out - thus, the
1577     * object on that map are no longer in memory. So check to see if the
1578     * players map changes, and if so, don't process any further.
1579     * If it does change, most likely we don't care about the results
1580     * of further conversation. Also, depending on the value of i,
1581     * the conversation would continue on the new map, which probably isn't
1582     * what is really wanted either.
1583     */
1584     void communicate(object *op, const char *txt) {
1585     object *npc;
1586     int i, mflags;
1587     sint16 x, y;
1588     mapstruct *mp, *orig_map = op->map;
1589    
1590     int flag=1; /*hasn't spoken to a NPC yet*/
1591     for(i = 0; i <= SIZEOFFREE2; i++) {
1592    
1593     mp = op->map;
1594     x = op->x + freearr_x[i];
1595     y = op->y + freearr_y[i];
1596    
1597     mflags = get_map_flags(mp, &mp, x, y, &x, &y);
1598     if (mflags & P_OUT_OF_MAP) continue;
1599    
1600     for(npc = get_map_ob(mp,x,y); npc != NULL; npc = npc->above) {
1601     if (npc->type == MAGIC_EAR) {
1602     (void) talk_to_wall(op, npc, txt); /* Maybe exit after 1. success? */
1603     if (orig_map != op->map) {
1604     LOG(llevDebug,"Warning: Forced to swap out very recent map - MAX_OBJECTS should probably be increased\n");
1605     return;
1606     }
1607     }
1608     else if (flag) {
1609     #if 0
1610     if (talk_to_npc(op, npc,txt))
1611     flag=0; /* Can be crowded */
1612     #else
1613     talk_to_npc(op, npc,txt);
1614     #endif
1615     if (orig_map != op->map) {
1616     LOG(llevDebug,"Warning: Forced to swap out very recent map - MAX_OBJECTS should probably be increased\n");
1617     return;
1618     }
1619     }
1620     }
1621     }
1622     }
1623    
1624     static int do_talk_npc(object* op, object* npc, object* override, const char* txt)
1625     {
1626     char* cp;
1627     char buf[MAX_BUF];
1628    
1629     if(override->msg == NULL || *override->msg != '@')
1630     return 0;
1631    
1632     cp = find_matching_message(op, override->msg, txt);
1633     if (cp) {
1634     sprintf(buf,"%s says:",query_name(npc));
1635     new_info_map(NDI_NAVY|NDI_UNIQUE, npc->map,buf);
1636     new_info_map(NDI_NAVY | NDI_UNIQUE, npc->map, cp);
1637     quest_apply_items(override,op->contr);
1638     free(cp);
1639     return 1;
1640     }
1641     return 0;
1642     }
1643    
1644     int talk_to_npc(object *op, object *npc, const char *txt) {
1645     object *cobj;
1646    
1647     /* Move this commone area up here - shouldn't cost much extra cpu
1648     * time, and makes the function more readable */
1649     /* Lauwenmark: Handle for plugin say event */
1650     if (op==npc) return 0;
1651     if (execute_event(npc, EVENT_SAY,op,NULL,txt,SCRIPT_FIX_ALL)!=0)
1652     return 0;
1653     /* Lauwenmark - Here we let the objects inside inventories hear and answer, too. */
1654     /* This allows the existence of "intelligent" weapons you can discuss with */
1655     for(cobj=npc->inv;cobj!=NULL; cobj = cobj->below)
1656     {
1657     if (execute_event(cobj, EVENT_SAY,npc,NULL,txt,SCRIPT_FIX_ALL)!=0)
1658     return 0;
1659     }
1660     for ( cobj = npc->inv; cobj; cobj = cobj->below )
1661     if ( quest_is_override_compatible( cobj, op ) )
1662     if ( do_talk_npc( op, npc, cobj, txt ) )
1663     return 1;
1664     return do_talk_npc( op, npc, npc, txt );
1665     }
1666    
1667     static int do_talk_wall(object* pl, object* npc, object* override, const char* txt)
1668     {
1669     char* cp;
1670     if(override->msg == NULL || *override->msg != '@')
1671     return 0;
1672    
1673     cp = find_matching_message(pl, override->msg, txt);
1674     if (!cp)
1675     return 0;
1676    
1677     new_info_map(NDI_NAVY | NDI_UNIQUE, npc->map,cp);
1678     use_trigger(npc);
1679     quest_apply_items(npc, pl->contr);
1680     free(cp);
1681    
1682     return 1;
1683     }
1684    
1685     int talk_to_wall(object* pl, object *npc, const char *txt) {
1686    
1687     object* inv;
1688    
1689     for ( inv = npc->inv; inv; inv = inv->below)
1690     if ( quest_is_override_compatible(inv, pl ) )
1691     if ( do_talk_wall( pl, npc, inv, txt ) )
1692     return 1;
1693    
1694     return do_talk_wall( pl, npc, npc, txt );;
1695     }
1696    
1697     /* find_mon_throw_ob() - modeled on find_throw_ob
1698     * This is probably overly simplistic as it is now - We want
1699     * monsters to throw things like chairs and other pieces of
1700     * furniture, even if they are not good throwable objects.
1701     * Probably better to have the monster throw a throwable object
1702     * first, then throw any non equipped weapon.
1703     */
1704    
1705     object *find_mon_throw_ob( object *op ) {
1706     object *tmp = NULL;
1707    
1708     if(op->head) tmp=op->head; else tmp=op;
1709    
1710     /* New throw code: look through the inventory. Grap the first legal is_thrown
1711     * marked item and throw it to the enemy.
1712     */
1713    
1714     for(tmp=op->inv;tmp;tmp=tmp->below) {
1715    
1716     /* Can't throw invisible objects or items that are applied */
1717     if(tmp->invisible || QUERY_FLAG(tmp,FLAG_APPLIED)) continue;
1718    
1719     if(QUERY_FLAG(tmp,FLAG_IS_THROWN))
1720     break;
1721    
1722     }
1723    
1724     #ifdef DEBUG_THROW
1725     LOG(llevDebug,"%s chooses to throw: %s (%d)\n",op->name,
1726     !(tmp)?"(nothing)":query_name(tmp),tmp?tmp->count:-1);
1727     #endif
1728    
1729     return tmp;
1730     }
1731    
1732     /* determine if we can 'detect' the enemy. Check for walls blocking the
1733     * los. Also, just because its hidden/invisible, we may be sensitive/smart
1734     * enough (based on Wis & Int) to figure out where the enemy is. -b.t.
1735     * modified by MSW to use the get_rangevector so that map tiling works
1736     * properly. I also so odd code in place that checked for x distance
1737     * OR y distance being within some range - that seemed wrong - both should
1738     * be within the valid range. MSW 2001-08-05
1739     * Returns 0 if enemy can not be detected, 1 if it is detected
1740     */
1741    
1742     int can_detect_enemy (object *op, object *enemy, rv_vector *rv) {
1743     int radius = MIN_MON_RADIUS, hide_discovery;
1744    
1745     /* null detection for any of these condtions always */
1746     if(!op || !enemy || !op->map || !enemy->map)
1747     return 0;
1748    
1749     /* If the monster (op) has no way to get to the enemy, do nothing */
1750     if (!on_same_map(op, enemy))
1751     return 0;
1752    
1753     get_rangevector(op, enemy, rv, 0);
1754    
1755     /* Monsters always ignore the DM */
1756     if ( ( op->type != PLAYER ) && QUERY_FLAG( enemy, FLAG_WIZ ) )
1757     return 0;
1758    
1759     /* simple check. Should probably put some range checks in here. */
1760     if(can_see_enemy(op,enemy)) return 1;
1761    
1762     /* The rest of this is for monsters. Players are on their own for
1763     * finding enemies!
1764     */
1765     if(op->type==PLAYER) return 0;
1766    
1767     /* Quality invisible? Bah, we wont see them w/o SEE_INVISIBLE
1768     * flag (which was already checked) in can_see_enmy (). Lets get out of here
1769     */
1770     if(enemy->invisible && (!enemy->contr || (!enemy->contr->tmp_invis && !enemy->contr->hidden)))
1771     return 0;
1772    
1773     /* use this for invis also */
1774     hide_discovery = op->stats.Int/5;
1775    
1776     /* Determine Detection radii */
1777     if(!enemy->hide) /* to detect non-hidden (eg dark/invis enemy) */
1778     radius = (op->stats.Wis/5)+1>MIN_MON_RADIUS?(op->stats.Wis/5)+1:MIN_MON_RADIUS;
1779     else { /* a level/INT/Dex adjustment for hiding */
1780     object *sk_hide;
1781     int bonus = (op->level/2) + (op->stats.Int/5);
1782    
1783     if(enemy->type==PLAYER) {
1784     if((sk_hide = find_skill_by_number(enemy,SK_HIDING)))
1785     bonus -= sk_hide->level;
1786     else {
1787     LOG(llevError,"can_detect_enemy() got hidden player w/o hiding skill!\n");
1788     make_visible(enemy);
1789     radius=radius<MIN_MON_RADIUS?MIN_MON_RADIUS:radius;
1790     }
1791     }
1792     else /* enemy is not a player */
1793     bonus -= enemy->level;
1794    
1795     radius += bonus/5;
1796     hide_discovery += bonus*5;
1797     } /* else creature has modifiers for hiding */
1798    
1799     /* Radii stealth adjustment. Only if you are stealthy
1800     * will you be able to sneak up closer to creatures */
1801     if(QUERY_FLAG(enemy,FLAG_STEALTH))
1802     radius = radius/2, hide_discovery = hide_discovery/3;
1803    
1804     /* Radii adjustment for enemy standing in the dark */
1805     if(op->map->darkness>0 && !stand_in_light(enemy)) {
1806     /* on dark maps body heat can help indicate location with infravision
1807     * undead don't have body heat, so no benefit detecting them.
1808     */
1809     if(QUERY_FLAG(op,FLAG_SEE_IN_DARK) && !is_true_undead(enemy))
1810     radius += op->map->darkness/2;
1811     else
1812     radius -= op->map->darkness/2;
1813    
1814     /* op next to a monster (and not in complete darkness)
1815     * the monster should have a chance to see you.
1816     */
1817     if(radius<MIN_MON_RADIUS && op->map->darkness<5 && rv->distance<=1)
1818     radius = MIN_MON_RADIUS;
1819     } /* if on dark map */
1820    
1821     /* Lets not worry about monsters that have incredible detection
1822     * radii, we only need to worry here about things the player can
1823     * (potentially) see. This is 13, as that is the maximum size the player
1824     * may have for their map - in that way, creatures at the edge will
1825     * do something. Note that the distance field in the
1826     * vector is real distance, so in theory this should be 18 to
1827     * find that.
1828     */
1829     if(radius>13) radius = 13;
1830    
1831     /* Enemy in range! Now test for detection */
1832     if ((int) rv->distance <= radius) {
1833     /* ah, we are within range, detected? take cases */
1834     if(!enemy->invisible) /* enemy in dark squares... are seen! */
1835     return 1;
1836    
1837     /* hidden or low-quality invisible */
1838     if(enemy->hide && (rv->distance <= 1) && (RANDOM()%100<=hide_discovery)) {
1839     make_visible(enemy);
1840     /* inform players of new status */
1841     if(enemy->type==PLAYER && player_can_view(enemy,op))
1842     new_draw_info_format(NDI_UNIQUE,0, enemy,
1843     "You are discovered by %s!",op->name);
1844     return 1; /* detected enemy */
1845     }
1846     else if (enemy->invisible) {
1847     /* Change this around - instead of negating the invisible, just
1848     * return true so that the mosnter that managed to detect you can
1849     * do something to you. Decreasing the duration of invisible
1850     * doesn't make a lot of sense IMO, as a bunch of stupid creatures
1851     * can then basically negate the spell. The spell isn't negated -
1852     * they just know where you are!
1853     */
1854     if ((RANDOM() % 50) <= hide_discovery) {
1855     if (enemy->type == PLAYER) {
1856     new_draw_info_format(NDI_UNIQUE,0, enemy,
1857     "You see %s noticing your position.", query_name(op));
1858     }
1859     return 1;
1860     }
1861     }
1862     } /* within range */
1863    
1864     /* Wasn't detected above, so still hidden */
1865     return 0;
1866     }
1867    
1868     /* determine if op stands in a lighted square. This is not a very
1869     * intellegent algorithm. For one thing, we ignore los here, SO it
1870     * is possible for a bright light to illuminate a player on the
1871     * other side of a wall (!).
1872     */
1873    
1874     int stand_in_light( object *op) {
1875     sint16 nx,ny;
1876     mapstruct *m;
1877    
1878    
1879     if(!op) return 0;
1880     if(op->glow_radius > 0) return 1;
1881    
1882     if(op->map) {
1883     int x, y, x1, y1;
1884    
1885    
1886    
1887     /* Check the spaces with the max light radius to see if any of them
1888     * have lights, and if any of them light the player enough, then return 1.
1889     */
1890     for (x = op->x - MAX_LIGHT_RADII; x <= op->x + MAX_LIGHT_RADII; x++) {
1891     for (y = op->y - MAX_LIGHT_RADII; y <= op->y + MAX_LIGHT_RADII; y++) {
1892     m = op->map;
1893     nx = x;
1894     ny = y;
1895    
1896     if (get_map_flags(m, &m, nx, ny, &nx, &ny) & P_OUT_OF_MAP) continue;
1897    
1898     x1 = abs(x - op->x)*abs(x - op->x);
1899     y1 = abs(y - op->y)*abs(y - op->y);
1900     if (isqrt(x1 + y1) < GET_MAP_LIGHT(m, nx, ny)) return 1;
1901     }
1902     }
1903     }
1904     return 0;
1905     }
1906    
1907    
1908     /* assuming no walls/barriers, lets check to see if its *possible*
1909     * to see an enemy. Note, "detection" is different from "seeing".
1910     * See can_detect_enemy() for more details. -b.t.
1911     * return 0 if can't be seen, 1 if can be
1912     */
1913    
1914     int can_see_enemy (object *op, object *enemy) {
1915     object *looker = op->head?op->head:op;
1916    
1917     /* safety */
1918     if(!looker||!enemy||!QUERY_FLAG(looker,FLAG_ALIVE))
1919     return 0;
1920    
1921     /* we dont give a full treatment of xrays here (shorter range than normal,
1922     * see through walls). Should we change the code elsewhere to make you
1923     * blind even if you can xray?
1924     */
1925     if(QUERY_FLAG(looker,FLAG_BLIND) && !QUERY_FLAG(looker,FLAG_XRAYS))
1926     return 0;
1927    
1928     /* checking for invisible things */
1929     if(enemy->invisible) {
1930     /* HIDDEN ENEMY. by definition, you can't see hidden stuff!
1931     * However,if you carry any source of light, then the hidden
1932     * creature is seeable (and stupid) */
1933    
1934     if(has_carried_lights(enemy)) {
1935     if(enemy->hide) {
1936     make_visible(enemy);
1937     new_draw_info(NDI_UNIQUE,0, enemy,
1938     "Your light reveals your hiding spot!");
1939     }
1940     return 1;
1941     } else if (enemy->hide) return 0;
1942    
1943     /* Invisible enemy. Break apart the check for invis undead/invis looker
1944     * into more simple checks - the QUERY_FLAG doesn't return 1/0 values,
1945     * and making it a conditional makes the code pretty ugly.
1946     */
1947     if (!QUERY_FLAG(looker,FLAG_SEE_INVISIBLE)) {
1948     if (makes_invisible_to(enemy, looker)) return 0;
1949     }
1950     } else if(looker->type==PLAYER) /* for players, a (possible) shortcut */
1951     if(player_can_view(looker,enemy)) return 1;
1952    
1953     /* ENEMY IN DARK MAP. Without infravision, the enemy is not seen
1954     * unless they carry a light or stand in light. Darkness doesnt
1955     * inhibit the undead per se (but we should give their archs
1956     * CAN_SEE_IN_DARK, this is just a safety
1957     * we care about the enemy maps status, not the looker.
1958     * only relevant for tiled maps, but it is possible that the
1959     * enemy is on a bright map and the looker on a dark - in that
1960     * case, the looker can still see the enemy
1961     */
1962     if(enemy->map->darkness>0&&!stand_in_light(enemy)
1963     &&(!QUERY_FLAG(looker,FLAG_SEE_IN_DARK)||
1964     !is_true_undead(looker)||!QUERY_FLAG(looker,FLAG_XRAYS)))
1965     return 0;
1966    
1967     return 1;
1968     }
1969