X-Git-Url: https://plomlompom.com/repos/?a=blobdiff_plain;f=src%2Fserver%2Fai.c;h=c25c277dcb73b70101c823e41e0f360b5698f204;hb=cdb90723dd636591bcfa98ebb165cf74a0cdeec7;hp=96e7ac35463ec562a95de8d9757fc6090d74772b;hpb=dd9d65ee727ac7e95801da0f8b5bae7009811802;p=plomrogue diff --git a/src/server/ai.c b/src/server/ai.c index 96e7ac3..c25c277 100644 --- a/src/server/ai.c +++ b/src/server/ai.c @@ -1,112 +1,186 @@ /* src/server/ai.c */ #include "ai.h" -#include /* uint8_t, uint16_t */ -#include /* free() */ -#include /* strlen(), memset() */ -#include "../common/try_malloc.h" /* try_malloc() */ -#include "../common/yx_uint16.h" /* struct yx_uint16 */ +#include /* NULL */ +#include /* uint8_t, uint16_t, uint32_t, UINT16_MAX */ #include "map_object_actions.h" /* get_moa_id_by_name() */ #include "map_objects.h" /* struct MapObj */ #include "world.h" /* global world */ -#include "yx_uint16.h" /* yx_uint16_cmp(), mv_yx_in_dir() */ -/* Change cardinal direction string ("NNE" etc.) of any length >1 pointed to by - * "path_ptr" one step clockwise ("NNE" -> "NEE", "NEE" -> "EEE" etc.). +#define N_DIRS 8 + + + +/* Write into "neighbors" scores of the eight immediate 2D neighbors of the + * "score_map" cell at "pos_i" (array index), as found in the directions north, + * north-east, east etc. (clockwise order). "max_score" is used for illegal + * neighborhoods (i.e. if the direction would lead beyond the map's border). */ -static void clockwise_path(char ** path_ptr); +static void get_neighbor_scores(uint32_t * score_map, uint16_t pos_i, + uint32_t max_score, uint32_t * neighbors); -/* Return dir char (north = "N" etc.) to enemy nearest to "origin" (beeline). */ -static char nearest_enemy_dir(struct yx_uint16 origin); +/* Iterate over scored cells in "score_map" of world.map's 2D geometry. Compare + * each cell's score against the score of its immediate neighbors in N_DIRS + * directions. If it's neighbors are low enough that the result would be lower + * than the current value, re-set it to world.map.dist_orthogonal points higher + * than its lowest-scored orthogonal neighbor or world.map.dist_diagonal points + * higher than its lowest-scored diagonal neighbor (whatever would result in a + * lower value). Repeat this whole process until all cells have settled on their + * final score. Ignore cells whose position in "score_map" fits cells of + * unreachable terrain in world.map.cells. Expect "max_score" to be the maximum + * score for cells, marking them as unreachable. + */ +static void dijkstra_map(uint32_t * score_map, uint32_t max_score); + +/* Return numpad char of direction ("8", "6", "2", "4" etc.) of enemy with the + * shortest path to "mo_origin". If no enemy is around, return 0. + */ +static char get_dir_to_nearest_enemy(struct MapObj * mo_origin); -static void clockwise_path(char ** path_ptr) +static void get_neighbor_scores(uint32_t * score_map, uint16_t pos_i, + uint32_t max_score, uint32_t * neighbors) { - char * path = * path_ptr; - char old_char = path[0]; - char new_char = 'N'; - if ('N' == old_char) + uint32_t map_size = world.map.size.y * world.map.size.x; + uint8_t i_dir; + for (i_dir = 0; i_dir < N_DIRS; neighbors[i_dir] = max_score, i_dir++); + uint8_t open_north = pos_i >= world.map.size.x; + uint8_t open_east = pos_i + 1 % world.map.size.x; + uint8_t open_south = pos_i + world.map.size.x < map_size; + uint8_t open_west = pos_i % world.map.size.x; + if (open_north) { - new_char = 'E'; + neighbors[0] = score_map[pos_i - world.map.size.x]; } - else if ('E' == old_char) + if (open_north && open_east) { - new_char = 'S'; + neighbors[1] = score_map[pos_i - world.map.size.x + 1]; } - else if ('S' == old_char) + if (open_east) { - new_char = 'W'; + neighbors[2] = score_map[pos_i + 1]; } - uint8_t len = strlen(path); - uint8_t i = 0; - for (; i < len; i++) + if (open_east && open_south) { - uint8_t next_i = i + 1; - if (next_i == len || old_char != path[next_i]) - { - break; - } + neighbors[3] = score_map[pos_i + 1 + world.map.size.x]; + } + if (open_south) + { + neighbors[4] = score_map[pos_i + world.map.size.x]; + } + if (open_south && open_west) + { + neighbors[5] = score_map[pos_i + world.map.size.x - 1]; + } + if (open_west) + { + neighbors[6] = score_map[pos_i - 1]; + } + if (open_west && open_north) + { + neighbors[7] = score_map[pos_i - 1 - world.map.size.x]; } - path[i] = new_char; } -static char nearest_enemy_dir(struct yx_uint16 origin) +static void dijkstra_map(uint32_t * score_map, uint32_t max_score) { - char * f_name = "nearest_enemy_dir()"; - struct MapObj * mo; - char sel = 0; - uint16_t dist_max = world.map.size.y; - if (world.map.size.x > world.map.size.y) + uint32_t i_scans, neighbors[N_DIRS], min_neighbor_o, min_neighbor_d; + uint32_t map_size = world.map.size.y * world.map.size.x; + uint16_t pos; + uint8_t scores_still_changing = 1; + uint8_t i_dirs; + for (i_scans = 0; scores_still_changing; i_scans++) { - dist_max = world.map.size.x; - } - uint8_t escape = 0; - uint8_t dist, j; - uint16_t i; - for (dist = 1; !escape && dist <= dist_max; dist++) - { - char * path = try_malloc(dist + 1, f_name); - memset(path, 'N', dist); - path[dist] = '\0'; - for (i = 0; !escape && i < (dist * 4); i++) + scores_still_changing = 0; + for (pos = 0; pos < map_size; pos++) { - clockwise_path(&path); - struct yx_uint16 testpos = origin; - for (j = 0; j < dist; j++) - { - testpos = mv_yx_in_dir(path[j], testpos); - } - if (yx_uint16_cmp(&testpos, &origin) || - testpos.y > world.map.size.y || testpos.x > world.map.size.x) - { - continue; - } - for (mo = world.map_objs; mo != 0; mo = mo->next) + if ('.' == world.map.cells[pos]) { - if (mo->lifepoints && 1 == yx_uint16_cmp(&testpos, &mo->pos)) + get_neighbor_scores(score_map, pos, max_score, neighbors); + min_neighbor_d = max_score; + min_neighbor_o = max_score; + for (i_dirs = 0; i_dirs < N_DIRS; i_dirs++) + { + if (!(i_dirs % 2) && min_neighbor_o > neighbors[i_dirs]) + { + min_neighbor_o = neighbors[i_dirs]; + } + else if (i_dirs % 2 && min_neighbor_d > neighbors[i_dirs]) + { + min_neighbor_d = neighbors[i_dirs]; + } + } + if (score_map[pos] > min_neighbor_o + world.map.dist_orthogonal) { - sel = path[0]; - escape = 1; - break; + score_map[pos] = min_neighbor_o + world.map.dist_orthogonal; + scores_still_changing = 1; + } + if (score_map[pos] > min_neighbor_d + world.map.dist_diagonal) + { + score_map[pos] = min_neighbor_d + world.map.dist_diagonal; + scores_still_changing = 1; } } } - free(path); } - return sel; } -extern void pretty_dumb_ai(struct MapObj * mo) +static char get_dir_to_nearest_enemy(struct MapObj * mo_origin) +{ + /* Calculate for each cell the distance to the nearest map actor that is + * not "mo_origin", with movement only possible in the directions of "dir". + * (Actors' own cells start with a distance of 0 towards themselves.) + */ + uint32_t map_size = world.map.size.y * world.map.size.x; + uint32_t max_score = UINT32_MAX - (world.map.dist_diagonal + 1); + uint32_t score_map[map_size]; + uint32_t i; + for (i = 0; i < map_size; i++) + { + score_map[i] = max_score; + } + struct MapObj * mo = world.map_objs; + for (; mo != NULL; mo = mo->next) + { + if (!mo->lifepoints || mo == mo_origin) + { + continue; + } + score_map[(mo->pos.y * world.map.size.x) + mo->pos.x] = 0; + } + dijkstra_map(score_map, max_score); + + /* Return direction of "mo_origin"'s lowest-scored neighbor cell. */ + uint32_t neighbors[N_DIRS]; + uint16_t pos_i = (mo_origin->pos.y * world.map.size.x) + mo_origin->pos.x; + get_neighbor_scores(score_map, pos_i, max_score, neighbors); + char dir_to_nearest_enemy = 0; + uint32_t min_neighbor = max_score; + char * dirs = "89632147"; /* get_neighbor_scores()'s clockwise dir order.*/ + for (i = 0; i < N_DIRS; i++) + { + if (min_neighbor > neighbors[i]) + { + min_neighbor = neighbors[i]; + dir_to_nearest_enemy = dirs[i]; + } + } + return dir_to_nearest_enemy; +} + + + +extern void ai(struct MapObj * mo) { mo->command = get_moa_id_by_name("wait"); - char sel = nearest_enemy_dir(mo->pos); + char sel = get_dir_to_nearest_enemy(mo); if (0 != sel) { mo->command = get_moa_id_by_name("move");