diff options
| -rw-r--r-- | main.c | 41 |
1 files changed, 23 insertions, 18 deletions
@@ -50,11 +50,8 @@ rand_in(unsigned int range) } kd_node_t * -try_neighbor(kd_node_t *node, unsigned int width, unsigned int height, int which) +try_neighbor(kd_node_t *node, unsigned int width, unsigned int height, int dx, int dy) { - int dx = which%3 - 1; - int dy = which/3 - 1; - if (dx < 0 && node->x < -dx) { return NULL; } else if (dx > 0 && node->x + dx >= width) { @@ -68,19 +65,25 @@ try_neighbor(kd_node_t *node, unsigned int width, unsigned int height, int which return node + (int)width*dy + dx; } +// Star pattern +int neighbor_order[][2] = { + { -1, -1 }, + { 0, +1 }, + { +1, -1 }, + { -1, 0 }, + { +1, +1 }, + { 0, -1 }, + { -1, +1 }, + { +1, 0 }, +}; + kd_node_t * next_neighbor(kd_node_t *node, unsigned int width, unsigned int height) { - unsigned int first = rand_in(9); - - for (unsigned int i = first; i < first + 9; ++i) { - int which = i%9; - if (which == 4) { - // Skip self - continue; - } - - kd_node_t *neighbor = try_neighbor(node, width, height, which); + unsigned int first = rand_in(8); + for (unsigned int i = first; i < first + 8; ++i) { + int *delta = neighbor_order[i%8]; + kd_node_t *neighbor = try_neighbor(node, width, height, delta[0], delta[1]); if (neighbor && !neighbor->added) { return neighbor; } @@ -101,10 +104,12 @@ remove_if_surrounded(kd_forest_t *kdf, kd_node_t *node, unsigned int width, unsi void remove_non_boundary(kd_forest_t *kdf, kd_node_t *node, unsigned int width, unsigned int height) { - for (int i = 0; i < 9; ++i) { - kd_node_t *neighbor = try_neighbor(node, width, height, i); - if (neighbor) { - remove_if_surrounded(kdf, neighbor, width, height); + for (int dy = -1; dy <= 1; ++dy) { + for (int dx = -1; dx <= 1; ++dx) { + kd_node_t *neighbor = try_neighbor(node, width, height, dx, dy); + if (neighbor) { + remove_if_surrounded(kdf, neighbor, width, height); + } } } } |