#include "cavegen.h" #include #include #include #define MAX_STEPS 200 #define NUM_WALKERS 100 enum direction { UP, LEFT, RIGHT, DOWN, NUM_DIRS, }; void create_cave( enum tile_type **map, struct point **open_tiles, int *num_open_tiles, struct point *up, struct point *down ) { // create a map consisting entirely of walls *map = malloc(sizeof(enum tile_type) * HEIGHT * WIDTH); for (int i = 0; i < HEIGHT; ++i) { for (int j = 0; j < WIDTH; ++j) { (*map)[i * WIDTH + j] = WALL; } } // start in the middle of the screen int start_x = WIDTH / 2; int start_y = HEIGHT / 2; // make the starting point GROUND (*map)[start_y * WIDTH + start_x] = GROUND; *open_tiles = malloc(sizeof(struct point) * HEIGHT * WIDTH); *num_open_tiles = 1; (*open_tiles)[0].x = start_x; (*open_tiles)[0].y = start_y; for (int i = 0; i < NUM_WALKERS; ++i) { // get a random open point struct point curr_point = (*open_tiles)[rand() % *num_open_tiles]; int x_pos = curr_point.x; int y_pos = curr_point.y; // iterate until the walk exits the array or MAX_STEPS is reached for (int j = 1; j < MAX_STEPS - 1 && x_pos < WIDTH - 1 && x_pos >= 1 && y_pos < HEIGHT - 1 && y_pos >= 1; ++j) { // add new open point if the current point is still a wall if ((*map)[y_pos * WIDTH + x_pos] == WALL) { (*open_tiles)[*num_open_tiles].x = x_pos; (*open_tiles)[*num_open_tiles].y = y_pos; ++(*num_open_tiles); } (*map)[y_pos * WIDTH + x_pos] = GROUND; // assign ground // move in a random direction enum direction dir = rand() % NUM_DIRS; switch (dir) { case UP : --y_pos; break; case LEFT : --x_pos; break; case RIGHT : ++x_pos; break; case DOWN : ++y_pos; break; default : exit(EXIT_FAILURE); // should not occur } } } // assign the up stair and remove from open tiles int in = rand() % *num_open_tiles; *up = (*open_tiles)[in]; (*open_tiles)[in] = (*open_tiles)[*num_open_tiles - 1]; --(*num_open_tiles); (*map)[up->y * WIDTH + up->x] = UP_STAIR; // assign the down stair and remove from open tiles in = rand() % *num_open_tiles; *down = (*open_tiles)[in]; (*open_tiles)[in] = (*open_tiles)[*num_open_tiles - 1]; --(*num_open_tiles); (*map)[down->y * WIDTH + down->x] = DOWN_STAIR; }