From 78028c8b652a4edf761b6f250c2fca4b6c576dee Mon Sep 17 00:00:00 2001 From: Piotr Hałaczkiewicz Date: Tue, 23 Jul 2013 09:56:54 +0200 Subject: Pathfinding code cleanup. Now uses binary heap defined in `db.h`. Walk requests now use A* (hard) pathfinding only to match game client behavior. Added defines for movement cost. Added some documentation & comments. --- src/map/mob.c | 2 +- src/map/path.c | 486 ++++++++++++++++++++++++++++----------------------------- src/map/path.h | 3 + src/map/pet.c | 2 +- src/map/unit.c | 12 +- 5 files changed, 254 insertions(+), 251 deletions(-) diff --git a/src/map/mob.c b/src/map/mob.c index 601ecd110..9cd05a8a3 100644 --- a/src/map/mob.c +++ b/src/map/mob.c @@ -1364,7 +1364,7 @@ int mob_randomwalk(struct mob_data *md,unsigned int tick) speed=iStatus->get_speed(&md->bl); for(i=c=0;iud.walkpath.path_len;i++){ // The next walk start time is calculated. if(md->ud.walkpath.path[i]&1) - c+=speed*14/10; + c+=speed*MOVE_DIAGONAL_COST/MOVE_COST; else c+=speed; } diff --git a/src/map/path.c b/src/map/path.c index 95895cb2a..32a4189bb 100644 --- a/src/map/path.c +++ b/src/map/path.c @@ -2,149 +2,61 @@ // For more information, see LICENCE in the main folder #include "../common/cbasetypes.h" +#include "../common/db.h" +#include "../common/malloc.h" #include "../common/nullpo.h" #include "../common/random.h" #include "../common/showmsg.h" -#include "../common/malloc.h" -#include "map.h" -#include "battle.h" + #include "path.h" +#include "map.h" #include #include #include +#define SET_OPEN 0 +#define SET_CLOSED 1 + +#define DIR_NORTH 1 +#define DIR_WEST 2 +#define DIR_SOUTH 4 +#define DIR_EAST 8 + +/// @name Structures and defines for A* pathfinding +/// @{ + +/// Path node +struct path_node { + struct path_node *parent; ///< pointer to parent (for path reconstruction) + short x; ///< X-coordinate + short y; ///< Y-coordinate + short g_cost; ///< Actual cost from start to this node + short f_cost; ///< g_cost + heuristic(this, goal) + short flag; ///< SET_OPEN / SET_CLOSED +}; + +/// Binary heap of path nodes +BHEAP_STRUCT_DECL(node_heap, struct path_node*); -#define MAX_HEAP 150 +/// Comparator for binary heap of path nodes (minimum cost at top) +#define NODE_MINTOPCMP(i,j) ((i)->f_cost - (j)->f_cost) -struct tmp_path { short x,y,dist,before,cost,flag;}; #define calc_index(x,y) (((x)+(y)*MAX_WALKPATH) & (MAX_WALKPATH*MAX_WALKPATH-1)) -const char walk_choices [3][3] = +/// Estimates the cost from (x0,y0) to (x1,y1). +/// This is inadmissible (overestimating) heuristic used by game client. +#define heuristic(x0, y0, x1, y1) (MOVE_COST * (abs((x1) - (x0)) + abs((y1) - (y0)))) // Manhattan distance +/// @} + +// Translates dx,dy into walking direction +static const unsigned char walk_choices [3][3] = { {1,0,7}, {2,-1,6}, {3,4,5}, }; -/*========================================== - * heap push (helper function) - *------------------------------------------*/ -static void push_heap_path(int *heap,struct tmp_path *tp,int index) -{ - int i,h; - - h = heap[0]; - heap[0]++; - - for( i = (h-1)/2; h > 0 && tp[index].cost < tp[heap[i+1]].cost; i = (h-1)/2 ) - heap[h+1] = heap[i+1], h = i; - - heap[h+1] = index; -} - -/*========================================== - * heap update (helper function) - * Move toward the root because cost has decreased. - *------------------------------------------*/ -static void update_heap_path(int *heap,struct tmp_path *tp,int index) -{ - int i,h; - - ARR_FIND( 0, heap[0], h, heap[h+1] == index ); - if( h == heap[0] ) - { - ShowError("update_heap_path bug\n"); - exit(EXIT_FAILURE); - } - - for( i = (h-1)/2; h > 0 && tp[index].cost < tp[heap[i+1]].cost; i = (h-1)/2 ) - heap[h+1] = heap[i+1], h = i; - - heap[h+1] = index; -} - -/*========================================== - * heap pop (helper function) - *------------------------------------------*/ -static int pop_heap_path(int *heap,struct tmp_path *tp) -{ - int i,h,k; - int ret,last; - - if( heap[0] <= 0 ) - return -1; - ret = heap[1]; - last = heap[heap[0]]; - heap[0]--; - - for( h = 0, k = 2; k < heap[0]; k = k*2+2 ) - { - if( tp[heap[k+1]].cost > tp[heap[k]].cost ) - k--; - heap[h+1] = heap[k+1], h = k; - } - - if( k == heap[0] ) - heap[h+1] = heap[k], h = k-1; - - for( i = (h-1)/2; h > 0 && tp[heap[i+1]].cost > tp[last].cost; i = (h-1)/2 ) - heap[h+1] = heap[i+1], h = i; - - heap[h+1]=last; - - return ret; -} - -/*========================================== - * calculate cost for the specified position - *------------------------------------------*/ -static int calc_cost(struct tmp_path *p,int16 x1,int16 y1) -{ - int xd = abs(x1 - p->x); - int yd = abs(y1 - p->y); - return (xd + yd)*10 + p->dist; -} - -/*========================================== - * attach/adjust path if neccessary - *------------------------------------------*/ -static int add_path(int *heap,struct tmp_path *tp,int16 x,int16 y,int dist,int before,int cost) -{ - int i; - - i = calc_index(x,y); - - if( tp[i].x == x && tp[i].y == y ) - { - if( tp[i].dist > dist ) - { - tp[i].dist = dist; - tp[i].before = before; - tp[i].cost = cost; - if( tp[i].flag ) - push_heap_path(heap,tp,i); - else - update_heap_path(heap,tp,i); - tp[i].flag = 0; - } - return 0; - } - - if( tp[i].x || tp[i].y ) - return 1; - - tp[i].x = x; - tp[i].y = y; - tp[i].dist = dist; - tp[i].before = before; - tp[i].cost = cost; - tp[i].flag = 0; - push_heap_path(heap,tp,i); - - return 0; -} - /*========================================== * Find the closest reachable cell, 'count' cells away from (x0,y0) in direction (dx,dy). * Income after the coordinates of the blow @@ -262,164 +174,250 @@ bool path_search_long(struct shootpath_data *spd,int16 m,int16 x0,int16 y0,int16 return true; } +/// @name A* pathfinding related functions +/// @{ + +/// Pushes path_node to the binary node_heap. +/// Ensures there is enough space in array to store new element. +static void heap_push_node(struct node_heap *heap, struct path_node *node) +{ + BHEAP_ENSURE(*heap, 1, 256); + BHEAP_PUSH(*heap, node, NODE_MINTOPCMP, swap_ptr); +} + +/// Updates path_node in the binary node_heap. +static int heap_update_node(struct node_heap *heap, struct path_node *node) +{ + int i; + ARR_FIND(0, BHEAP_LENGTH(*heap), i, BHEAP_DATA(*heap)[i] == node); + if (i == BHEAP_LENGTH(*heap)) { + ShowError("heap_update_node: node not found\n"); + return 1; + } + BHEAP_POPINDEX(*heap, i, NODE_MINTOPCMP, swap_ptr); + BHEAP_PUSH(*heap, node, NODE_MINTOPCMP, swap_ptr); + return 0; +} + +/// Path_node processing in A* pathfinding. +/// Adds new node to heap and updates/re-adds old ones if necessary. +static int add_path(struct node_heap *heap, struct path_node *tp, int16 x, int16 y, int g_cost, struct path_node *parent, int h_cost) +{ + int i = calc_index(x, y); + + if (tp[i].x == x && tp[i].y == y) { // We processed this node before + if (g_cost < tp[i].g_cost) { // New path to this node is better than old one + // Update costs and parent + tp[i].g_cost = g_cost; + tp[i].parent = parent; + tp[i].f_cost = g_cost + h_cost; + if (tp[i].flag == SET_CLOSED) { + heap_push_node(heap, &tp[i]); // Put it in open set again + } + else if (heap_update_node(heap, &tp[i])) { + return 1; + } + tp[i].flag = SET_OPEN; + } + return 0; + } + + if (tp[i].x || tp[i].y) // Index is already taken; see `tp` array FIXME for details + return 1; + + // New node + tp[i].x = x; + tp[i].y = y; + tp[i].g_cost = g_cost; + tp[i].parent = parent; + tp[i].f_cost = g_cost + h_cost; + tp[i].flag = SET_OPEN; + heap_push_node(heap, &tp[i]); + return 0; +} +///@} + /*========================================== * path search (x0,y0)->(x1,y1) * wpd: path info will be written here * flag: &1 = easy path search only * cell: type of obstruction to check for *------------------------------------------*/ -bool path_search(struct walkpath_data *wpd,int16 m,int16 x0,int16 y0,int16 x1,int16 y1,int flag,cell_chk cell) +bool path_search(struct walkpath_data *wpd, int16 m, int16 x0, int16 y0, int16 x1, int16 y1, int flag, cell_chk cell) { - int heap[MAX_HEAP+1]; - struct tmp_path tp[MAX_WALKPATH*MAX_WALKPATH]; - register int i,j,len,x,y,dx,dy; - int rp,xs,ys; + register int i, j, x, y, dx, dy; struct map_data *md; struct walkpath_data s_wpd; - if( wpd == NULL ) + if (wpd == NULL) wpd = &s_wpd; // use dummy output variable - if( !map[m].cell ) + if (!map[m].cell) return false; md = &map[m]; #ifdef CELL_NOSTACK //Do not check starting cell as that would get you stuck. - if( x0 < 0 || x0 >= md->xs || y0 < 0 || y0 >= md->ys ) + if (x0 < 0 || x0 >= md->xs || y0 < 0 || y0 >= md->ys) #else - if( x0 < 0 || x0 >= md->xs || y0 < 0 || y0 >= md->ys /*|| md->getcellp(md,x0,y0,cell)*/ ) + if (x0 < 0 || x0 >= md->xs || y0 < 0 || y0 >= md->ys /*|| md->getcellp(md,x0,y0,cell)*/) #endif return false; - if( x1 < 0 || x1 >= md->xs || y1 < 0 || y1 >= md->ys || md->getcellp(md,x1,y1,cell) ) + + // Check destination cell + if (x1 < 0 || x1 >= md->xs || y1 < 0 || y1 >= md->ys || md->getcellp(md,x1,y1,cell)) return false; - // calculate (sgn(x1-x0), sgn(y1-y0)) - dx = ((dx = x1-x0)) ? ((dx<0) ? -1 : 1) : 0; - dy = ((dy = y1-y0)) ? ((dy<0) ? -1 : 1) : 0; + if (flag&1) { + // Try finding direct path to target + // Direct path goes diagonally first, then in straight line. - // try finding direct path to target - x = x0; - y = y0; - i = 0; - while( i < ARRAYLENGTH(wpd->path) ) - { - wpd->path[i] = walk_choices[-dy + 1][dx + 1]; - i++; + // calculate (sgn(x1-x0), sgn(y1-y0)) + dx = ((dx = x1-x0)) ? ((dx<0) ? -1 : 1) : 0; + dy = ((dy = y1-y0)) ? ((dy<0) ? -1 : 1) : 0; - x += dx; - y += dy; + x = x0; // Current position = starting cell + y = y0; + i = 0; + while( i < ARRAYLENGTH(wpd->path) ) + { + wpd->path[i] = walk_choices[-dy + 1][dx + 1]; + i++; - if( x == x1 ) dx = 0; - if( y == y1 ) dy = 0; + x += dx; // Advance current position + y += dy; - if( dx == 0 && dy == 0 ) - break; // success - if( md->getcellp(md,x,y,cell) ) - break; // obstacle = failure - } + if( x == x1 ) dx = 0; // destination x reached, no longer move along x-axis + if( y == y1 ) dy = 0; // destination y reached, no longer move along y-axis - if( x == x1 && y == y1 ) - { //easy path successful. - wpd->path_len = i; - wpd->path_pos = 0; - return true; + if( dx == 0 && dy == 0 ) + break; // success + if( md->getcellp(md,x,y,cell) ) + break; // obstacle = failure + } + + if( x == x1 && y == y1 ) + { // easy path successful. + wpd->path_len = i; + wpd->path_pos = 0; + return true; + } + + return false; // easy path unsuccessful } + else { // !(flag&1) + // A* (A-star) pathfinding + // We always use A* for finding walkpaths because it is what game client uses. + // Easy pathfinding cuts corners of non-walkable cells, but client always walks around it. + + BHEAP_STRUCT_VAR(node_heap, open_set); // 'Open' set + + // FIXME: This array is too small to ensure all paths shorter than MAX_WALKPATH + // can be found without node collision: calc_index(node1) = calc_index(node2). + // Figure out more proper size or another way to keep track of known nodes. + struct path_node tp[MAX_WALKPATH * MAX_WALKPATH]; + struct path_node *current, *it; + int xs = md->xs - 1; + int ys = md->ys - 1; + int len = 0; + memset(tp, 0, sizeof(tp)); + + // Start node + i = calc_index(x0, y0); + tp[i].parent = NULL; + tp[i].x = x0; + tp[i].y = y0; + tp[i].g_cost = 0; + tp[i].f_cost = heuristic(x0, y0, x1, y1); + tp[i].flag = SET_OPEN; + + heap_push_node(&open_set, &tp[i]); // Put start node to 'open' set + for(;;) + { + int e = 0; // error flag - if( flag&1 ) - return false; + // Saves allowed directions for the current cell. Diagonal directions + // are only allowed if both directions around it are allowed. This is + // to prevent cutting corner of nearby wall. + // For example, you can only go NW from the current cell, if you can + // go N *and* you can go W. Otherwise you need to walk around the + // (corner of the) non-walkable cell. + int allowed_dirs = 0; - memset(tp,0,sizeof(tp)); - - i=calc_index(x0,y0); - tp[i].x=x0; - tp[i].y=y0; - tp[i].dist=0; - tp[i].before=0; - tp[i].cost=calc_cost(&tp[i],x1,y1); - tp[i].flag=0; - heap[0]=0; - push_heap_path(heap,tp,calc_index(x0,y0)); - xs = md->xs - 1; // Place by subtracting a pre- - ys = md->ys-1; - - for(;;) - { - int e=0,f=0,dist,cost,dc[4]={0,0,0,0}; + int g_cost; - if(heap[0]==0) - return false; - rp = pop_heap_path(heap,tp); - x = tp[rp].x; - y = tp[rp].y; - dist = tp[rp].dist + 10; - cost = tp[rp].cost; - - if(x==x1 && y==y1) - break; - - // dc[0] : y++ Incremental cost at the time - // dc[1] : x-- - // dc[2] : y-- - // dc[3] : x++ - - if(y < ys && !md->getcellp(md,x ,y+1,cell)) { - f |= 1; dc[0] = (y >= y1 ? 20 : 0); - e+=add_path(heap,tp,x ,y+1,dist,rp,cost+dc[0]); // (x, y+1) - } - if(x > 0 && !md->getcellp(md,x-1,y ,cell)) { - f |= 2; dc[1] = (x <= x1 ? 20 : 0); - e+=add_path(heap,tp,x-1,y ,dist,rp,cost+dc[1]); // (x-1, y ) - } - if(y > 0 && !md->getcellp(md,x ,y-1,cell)) { - f |= 4; dc[2] = (y <= y1 ? 20 : 0); - e+=add_path(heap,tp,x ,y-1,dist,rp,cost+dc[2]); // (x , y-1) - } - if(x < xs && !md->getcellp(md,x+1,y ,cell)) { - f |= 8; dc[3] = (x >= x1 ? 20 : 0); - e+=add_path(heap,tp,x+1,y ,dist,rp,cost+dc[3]); // (x+1, y ) - } - if( (f & (2+1)) == (2+1) && !md->getcellp(md,x-1,y+1,cell)) - e+=add_path(heap,tp,x-1,y+1,dist+4,rp,cost+dc[1]+dc[0]-6); // (x-1, y+1) - if( (f & (2+4)) == (2+4) && !md->getcellp(md,x-1,y-1,cell)) - e+=add_path(heap,tp,x-1,y-1,dist+4,rp,cost+dc[1]+dc[2]-6); // (x-1, y-1) - if( (f & (8+4)) == (8+4) && !md->getcellp(md,x+1,y-1,cell)) - e+=add_path(heap,tp,x+1,y-1,dist+4,rp,cost+dc[3]+dc[2]-6); // (x+1, y-1) - if( (f & (8+1)) == (8+1) && !md->getcellp(md,x+1,y+1,cell)) - e+=add_path(heap,tp,x+1,y+1,dist+4,rp,cost+dc[3]+dc[0]-6); // (x+1, y+1) - tp[rp].flag=1; - if(e || heap[0]>=MAX_HEAP-5) - return false; - } + if (BHEAP_LENGTH(open_set) == 0) { + BHEAP_CLEAR(open_set); + return false; + } - if( !(x==x1 && y==y1) ) // will never happen... - return false; + current = BHEAP_PEEK(open_set); // Look for the lowest f_cost node in the 'open' set + BHEAP_POP(open_set, NODE_MINTOPCMP, swap_ptr); // Remove it from 'open' set - for(len=0,i=rp;len<100 && i!=calc_index(x0,y0);i=tp[i].before,len++); - if(len==100 || len>=sizeof(wpd->path)) - return false; + x = current->x; + y = current->y; + g_cost = current->g_cost; + + current->flag = SET_CLOSED; // Add current node to 'closed' set - wpd->path_len = len; - wpd->path_pos = 0; - for(i=rp,j=len-1;j>=0;i=tp[i].before,j--) { - int dx = tp[i].x - tp[tp[i].before].x; - int dy = tp[i].y - tp[tp[i].before].y; - uint8 dir; - if( dx == 0 ) { - dir = (dy > 0 ? 0 : 4); - } else if( dx > 0 ) { - dir = (dy == 0 ? 6 : (dy < 0 ? 5 : 7) ); - } else { - dir = (dy == 0 ? 2 : (dy > 0 ? 1 : 3) ); + if (x == x1 && y == y1) { + BHEAP_CLEAR(open_set); + break; + } + + if (y < ys && !md->getcellp(md, x, y+1, cell)) allowed_dirs |= DIR_NORTH; + if (y > 0 && !md->getcellp(md, x, y-1, cell)) allowed_dirs |= DIR_SOUTH; + if (x < xs && !md->getcellp(md, x+1, y, cell)) allowed_dirs |= DIR_EAST; + if (x > 0 && !md->getcellp(md, x-1, y, cell)) allowed_dirs |= DIR_WEST; + +#define chk_dir(d) ((allowed_dirs & (d)) == (d)) + // Process neighbors of current node + // TODO: Processing order affects chosen path if there is more than one path with same cost. + // In few cases path found by server will be different than path found by game client. + if (chk_dir(DIR_SOUTH)) + e += add_path(&open_set, tp, x, y-1, g_cost + MOVE_COST, current, heuristic(x, y-1, x1, y1)); // (x, y-1) 4 + if (chk_dir(DIR_SOUTH|DIR_WEST) && !md->getcellp(md, x-1, y-1, cell)) + e += add_path(&open_set, tp, x-1, y-1, g_cost + MOVE_DIAGONAL_COST, current, heuristic(x-1, y-1, x1, y1)); // (x-1, y-1) 3 + if (chk_dir(DIR_WEST)) + e += add_path(&open_set, tp, x-1, y, g_cost + MOVE_COST, current, heuristic(x-1, y, x1, y1)); // (x-1, y) 2 + if (chk_dir(DIR_NORTH|DIR_WEST) && !md->getcellp(md, x-1, y+1, cell)) + e += add_path(&open_set, tp, x-1, y+1, g_cost + MOVE_DIAGONAL_COST, current, heuristic(x-1, y+1, x1, y1)); // (x-1, y+1) 1 + if (chk_dir(DIR_NORTH)) + e += add_path(&open_set, tp, x, y+1, g_cost + MOVE_COST, current, heuristic(x, y+1, x1, y1)); // (x, y+1) 0 + if (chk_dir(DIR_NORTH|DIR_EAST) && !md->getcellp(md, x+1, y+1, cell)) + e += add_path(&open_set, tp, x+1, y+1, g_cost + MOVE_DIAGONAL_COST, current, heuristic(x+1, y+1, x1, y1)); // (x+1, y+1) 7 + if (chk_dir(DIR_EAST)) + e += add_path(&open_set, tp, x+1, y, g_cost + MOVE_COST, current, heuristic(x+1, y, x1, y1)); // (x+1, y) 6 + if (chk_dir(DIR_SOUTH|DIR_EAST) && !md->getcellp(md, x+1, y-1, cell)) + e += add_path(&open_set, tp, x+1, y-1, g_cost + MOVE_DIAGONAL_COST, current, heuristic(x+1, y-1, x1, y1)); // (x+1, y-1) 5 +#undef chk_dir + if (e) { + BHEAP_CLEAR(open_set); + return false; + } } - wpd->path[j] = dir; - } - return true; + for (it = current; it->parent != NULL; it = it->parent, len++); + if (len > sizeof(wpd->path)) { + return false; + } + + // Recreate path + wpd->path_len = len; + wpd->path_pos = 0; + for (it = current, j = len-1; j >= 0; it = it->parent, j--) { + dx = it->x - it->parent->x; + dy = it->y - it->parent->y; + wpd->path[j] = walk_choices[-dy + 1][dx + 1]; + } + return true; + } // A* end + + return false; } -//Distance functions, taken from http://www.flpcode.com/articles/article_fastdistance.shtml +//Distance functions, taken from http://www.flipcode.com/articles/article_fastdistance.shtml int check_distance(int dx, int dy, int distance) { #ifdef CIRCULAR_AREA @@ -439,7 +437,7 @@ unsigned int distance(int dx, int dy) if ( dx < 0 ) dx = -dx; if ( dy < 0 ) dy = -dy; - //There appears to be something wrong with the aproximation below when either dx/dy is 0! [Skotlex] + //There appears to be something wrong with the approximation below when either dx/dy is 0! [Skotlex] if ( dx == 0 ) return dy; if ( dy == 0 ) return dx; diff --git a/src/map/path.h b/src/map/path.h index b1ca71955..5bc551dc9 100644 --- a/src/map/path.h +++ b/src/map/path.h @@ -6,6 +6,9 @@ #include "map.h" // enum cell_chk +#define MOVE_COST 10 +#define MOVE_DIAGONAL_COST 14 + #define MAX_WALKPATH 32 struct walkpath_data { diff --git a/src/map/pet.c b/src/map/pet.c index 2697e8128..3e7019806 100644 --- a/src/map/pet.c +++ b/src/map/pet.c @@ -817,7 +817,7 @@ static int pet_randomwalk(struct pet_data *pd,unsigned int tick) } for(i=c=0;iud.walkpath.path_len;i++){ if(pd->ud.walkpath.path[i]&1) - c+=pd->status.speed*14/10; + c+=pd->status.speed*MOVE_DIAGONAL_COST/MOVE_COST; else c+=pd->status.speed; } diff --git a/src/map/unit.c b/src/map/unit.c index 4a8a87920..7c65594ca 100644 --- a/src/map/unit.c +++ b/src/map/unit.c @@ -107,9 +107,9 @@ int unit_walktoxy_sub(struct block_list *bl) ud->walkpath.path_len--; dir = ud->walkpath.path[ud->walkpath.path_len]; if(dir&1) - i-=14; + i -= MOVE_DIAGONAL_COST; else - i-=10; + i -= MOVE_COST; ud->to_x -= dirx[dir]; ud->to_y -= diry[dir]; } @@ -126,7 +126,7 @@ int unit_walktoxy_sub(struct block_list *bl) if(ud->walkpath.path_pos>=ud->walkpath.path_len) i = -1; else if(ud->walkpath.path[ud->walkpath.path_pos]&1) - i = iStatus->get_speed(bl)*14/10; + i = iStatus->get_speed(bl)*MOVE_DIAGONAL_COST/MOVE_COST; else i = iStatus->get_speed(bl); if( i > 0) @@ -346,14 +346,16 @@ int unit_walktoxy( struct block_list *bl, short x, short y, int flag) if( ud == NULL) return 0; - path_search(&wpd, bl->m, bl->x, bl->y, x, y, flag&1, CELL_CHKNOPASS); // Count walk path cells + if (!path_search(&wpd, bl->m, bl->x, bl->y, x, y, flag&1, CELL_CHKNOPASS)) // Count walk path cells + return 0; + #ifdef OFFICIAL_WALKPATH if( !path_search_long(NULL, bl->m, bl->x, bl->y, x, y, CELL_CHKNOPASS) // Check if there is an obstacle between && (wpd.path_len > (battle_config.max_walk_path/17)*14) // Official number of walkable cells is 14 if and only if there is an obstacle between. [malufett] && (bl->type != BL_NPC) ) // If type is a NPC, please disregard. return 0; #endif - if( (battle_config.max_walk_path < wpd.path_len) && (bl->type != BL_NPC) ) + if ((wpd.path_len > battle_config.max_walk_path) && (bl->type != BL_NPC)) return 0; if (flag&4 && DIFF_TICK(ud->canmove_tick, iTimer->gettick()) > 0 && -- cgit v1.2.3-70-g09d2