51 lines
1.4 KiB
C
51 lines
1.4 KiB
C
#include <wildcards.h>
|
|
#include <stdio.h>
|
|
|
|
// Queries can have wildcard terms that can match multiple instances of a
|
|
// relationship or relationship target.
|
|
|
|
typedef struct {
|
|
int amount;
|
|
} Eats;
|
|
|
|
int main(int argc, char *argv[]) {
|
|
ecs_world_t *ecs = ecs_init_w_args(argc, argv);
|
|
|
|
ECS_COMPONENT(ecs, Eats);
|
|
ECS_TAG(ecs, Apples);
|
|
ECS_TAG(ecs, Pears);
|
|
|
|
// Create a query that matches edible components
|
|
ecs_query_t *q = ecs_query(ecs, {
|
|
.filter.terms = {{ .id = ecs_pair(ecs_id(Eats), EcsWildcard ) }}
|
|
});
|
|
|
|
// Create a few entities that match the query
|
|
ecs_entity_t bob = ecs_new_entity(ecs, "Bob");
|
|
ecs_set_pair(ecs, bob, Eats, Apples, {10});
|
|
ecs_set_pair(ecs, bob, Eats, Pears, {5});
|
|
|
|
ecs_entity_t alice = ecs_new_entity(ecs, "Alice");
|
|
ecs_set_pair(ecs, alice, Eats, Apples, {4});
|
|
|
|
// Iterate the query
|
|
ecs_iter_t it = ecs_query_iter(ecs, q);
|
|
while (ecs_query_next(&it)) {
|
|
Eats *eats = ecs_field(&it, Eats, 1);
|
|
ecs_id_t pair = ecs_field_id(&it, 1);
|
|
ecs_entity_t food = ecs_pair_second(ecs, pair);
|
|
|
|
for (int i = 0; i < it.count; i ++) {
|
|
printf("%s eats %d %s\n", ecs_get_name(ecs, it.entities[i]),
|
|
eats[i].amount, ecs_get_name(ecs, food));
|
|
}
|
|
}
|
|
|
|
// Output:
|
|
// Bob eats 10 Apples
|
|
// Bob eats 5 Pears
|
|
// Alice eats 4 Apples
|
|
|
|
return ecs_fini(ecs);
|
|
}
|