Updated homunculus walk behavior

* Fixes #1950.
* Updated homunculus walk behavior to closer mimic official behavior.
* Homunculus will now stop in a random 3x3 area around the master.
* Homunculus will no longer get stuck when looking for an empty cell when supporting the master during attacks.
Thanks to @dragonis1701!

src/map/clif.c

@@ -14629,7 +14629,7 @@ void clif_parse_HomMoveToMaster(int fd, struct map_session_data *sd){
 	else
 		return;
 
-	unit_calc_pos(bl, sd->bl.x, sd->bl.y, sd->ud.dir);
+	unit_calc_pos(bl, sd->bl.x, sd->bl.y);
 	ud = unit_bl2ud(bl);
 	unit_walktoxy(bl, ud->to_x, ud->to_y, 4);
 }

src/map/elemental.c

@@ -243,7 +243,7 @@ int elemental_data_received(struct s_elemental *ele, bool flag) {
 		ed->bl.m = sd->bl.m;
 		ed->bl.x = sd->bl.x;
 		ed->bl.y = sd->bl.y;
-		unit_calc_pos(&ed->bl, sd->bl.x, sd->bl.y, sd->ud.dir);
+		unit_calc_pos(&ed->bl, sd->bl.x, sd->bl.y);
 		ed->bl.x = ed->ud.to_x;
 		ed->bl.y = ed->ud.to_y;
 

src/map/homunculus.c

@@ -1033,7 +1033,7 @@ void hom_alloc(struct map_session_data *sd, struct s_homunculus *hom)
 	hd->bl.m = sd->bl.m;
 	hd->bl.x = sd->bl.x;
 	hd->bl.y = sd->bl.y;
-	unit_calc_pos(&hd->bl, sd->bl.x, sd->bl.y, sd->ud.dir);
+	unit_calc_pos(&hd->bl, sd->bl.x, sd->bl.y);
 	hd->bl.x = hd->ud.to_x;
 	hd->bl.y = hd->ud.to_y;
 

src/map/mercenary.c

@@ -372,7 +372,7 @@ bool mercenary_recv_data(struct s_mercenary *merc, bool flag)
 		md->bl.m = sd->bl.m;
 		md->bl.x = sd->bl.x;
 		md->bl.y = sd->bl.y;
-		unit_calc_pos(&md->bl, sd->bl.x, sd->bl.y, sd->ud.dir);
+		unit_calc_pos(&md->bl, sd->bl.x, sd->bl.y);
 		md->bl.x = md->ud.to_x;
 		md->bl.y = md->ud.to_y;
 

src/map/pet.c

@@ -449,7 +449,7 @@ int pet_data_init(struct map_session_data *sd, struct s_pet *pet)
 	pd->bl.m = sd->bl.m;
 	pd->bl.x = sd->bl.x;
 	pd->bl.y = sd->bl.y;
-	unit_calc_pos(&pd->bl, sd->bl.x, sd->bl.y, sd->ud.dir);
+	unit_calc_pos(&pd->bl, sd->bl.x, sd->bl.y);
 	pd->bl.x = pd->ud.to_x;
 	pd->bl.y = pd->ud.to_y;
 
@@ -1148,7 +1148,7 @@ static int pet_ai_sub_hard(struct pet_data *pd, struct map_session_data *sd, uns
 		if(pd->ud.walktimer != INVALID_TIMER && check_distance_blxy(&sd->bl, pd->ud.to_x,pd->ud.to_y, 3))
 			return 0; // Already walking to him
 
-		unit_calc_pos(&pd->bl, sd->bl.x, sd->bl.y, sd->ud.dir);
+		unit_calc_pos(&pd->bl, sd->bl.x, sd->bl.y);
 
 		if(!unit_walktoxy(&pd->bl,pd->ud.to_x,pd->ud.to_y,0))
 			pet_randomwalk(pd,tick);

src/map/unit.c

@@ -2384,12 +2384,10 @@ bool unit_can_reach_bl(struct block_list *bl,struct block_list *tbl, int range,
  * @param bl: Object to calculate position
  * @param tx: X coordinate to go to
  * @param ty: Y coordinate to go to
- * @param dir: Direction which to be 2 cells from master's position
  * @return Success(0); Fail(1);
  */
-int unit_calc_pos(struct block_list *bl, int tx, int ty, uint8 dir)
+int unit_calc_pos(struct block_list *bl, int tx, int ty)
 {
-	int dx, dy, x, y;
 	struct unit_data *ud = unit_bl2ud(bl);
 
 	nullpo_ret(ud);
@@ -2400,64 +2398,15 @@ int unit_calc_pos(struct block_list *bl, int tx, int ty, uint8 dir)
 	ud->to_x = tx;
 	ud->to_y = ty;
 
-	// 2 cells from Master Position
-	dx = -dirx[dir] * 2;
-	dy = -diry[dir] * 2;
-	x = tx + dx;
-	y = ty + dy;
+	map_search_freecell(bl, bl->m, &ud->to_x, &ud->to_y, 3, 3, 1|2|4);
 
-	if( !unit_can_reach_pos(bl, x, y, 0) ) {
-		if( dx > 0 )
-			x--;
-		else if( dx < 0 )
-			x++;
+	if (!unit_can_reach_pos(bl, ud->to_x, ud->to_y, 0)) { // Attempt once more
+		map_search_freecell(bl, bl->m, &ud->to_x, &ud->to_y, 3, 3, 1|2|4);
 
-		if( dy > 0 )
-			y--;
-		else if( dy < 0 )
-			y++;
-
-		if( !unit_can_reach_pos(bl, x, y, 0) ) {
-			int i;
-
-			for( i = 0; i < 12; i++ ) {
-				int k = rnd()%8; // Pick a Random Dir
-
-				dx = -dirx[k] * 2;
-				dy = -diry[k] * 2;
-				x = tx + dx;
-				y = ty + dy;
-
-				if( unit_can_reach_pos(bl, x, y, 0) )
-					break;
-				else {
-					if( dx > 0 )
-						x--;
-					else if( dx < 0 )
-						x++;
-
-					if( dy > 0 )
-						y--;
-					else if( dy < 0 )
-						y++;
-
-					if( unit_can_reach_pos(bl, x, y, 0) )
-						break;
-				}
-			}
-
-			if( i == 12 ) {
-				x = tx; y = tx; // Exactly Master Position
-
-				if( !unit_can_reach_pos(bl, x, y, 0) )
-					return 1;
-			}
-		}
+		if (!unit_can_reach_pos(bl, ud->to_x, ud->to_y, 0))
+			return 1;
 	}
 
-	ud->to_x = x;
-	ud->to_y = y;
-
 	return 0;
 }
 

src/map/unit.h

@@ -112,7 +112,7 @@ int unit_walktoxy(struct block_list *bl, short x, short y, unsigned char flag);
 int unit_walktobl(struct block_list *bl, struct block_list *target, int range, unsigned char flag);
 void unit_run_hit(struct block_list *bl, struct status_change *sc, struct map_session_data *sd, enum sc_type type);
 bool unit_run(struct block_list *bl, struct map_session_data *sd, enum sc_type type);
-int unit_calc_pos(struct block_list *bl, int tx, int ty, uint8 dir);
+int unit_calc_pos(struct block_list *bl, int tx, int ty);
 int unit_delay_walktoxy_timer(int tid, unsigned int tick, int id, intptr_t data);
 int unit_delay_walktobl_timer(int tid, unsigned int tick, int id, intptr_t data);