Input test.

src/rpg/entity/entity.c

@@ -12,12 +12,11 @@
 entity_t ENTITIES[ENTITY_COUNT];
 
 entitycallbacks_t ENTITY_CALLBACKS[ENTITY_TYPE_COUNT] = {
-    [ENTITY_TYPE_NULL] = {
-      .init = NULL
-    },
+    [ENTITY_TYPE_NULL] = { 0 },
     
     [ENTITY_TYPE_PLAYER] = {
-      .init = playerInit
+      .init = playerInit,
+      .update = playerUpdate
     },
 };
 
@@ -31,4 +30,23 @@ void entityInit(entity_t *entity, const entitytype_t type) {
   memoryZero(entity, sizeof(entity_t));
   entity->type = type;
   ENTITY_CALLBACKS[type].init(entity);
+}
+
+void entityUpdate(entity_t *entity) {
+  assertNotNull(entity, "Entity cannot be NULL");
+  assertNotNull(
+    ENTITY_CALLBACKS[entity->type].update,
+    "Entity type has no update"
+  );
+
+  ENTITY_CALLBACKS[entity->type].update(entity);
+}
+
+entity_t * entityGetAt(const uint8_t x, const uint8_t y) {
+  entity_t *e = ENTITIES;
+  do {
+    if(e->type && e->x == x && e->y == y) return e;
+    e++;
+  } while(e < (ENTITIES + ENTITY_COUNT));
+  return NULL;
 }