input

src/rpg/entity/entity.c

@@ -39,9 +39,58 @@ void entityUpdate(entity_t *entity) {
     "Entity type has no update"
   );
 
+  // Handle subpixel movement
+  if(entity->subX < 0) {
+    entity->subX++;
+  } else if(entity->subY < 0) {
+    entity->subY++;
+  } else if(entity->subX > 0) {
+    entity->subX--;
+  } else if(entity->subY > 0) {
+    entity->subY--;
+  }
+
+  // Entity-Type handling
   ENTITY_CALLBACKS[entity->type].update(entity);
 }
 
+void entityTurn(entity_t *entity, const entitydir_t dir) {
+  assertNotNull(entity, "Entity cannot be NULL");
+  assertFalse(entityIsWalking(entity), "Entity is currently walking");
+  entity->dir = dir;
+}
+
+void entityWalk(entity_t *entity) {
+  assertNotNull(entity, "Entity cannot be NULL");
+  assertFalse(entityIsWalking(entity), "Entity is already walking");
+
+  switch(entity->dir) {
+    case ENTITY_DIR_UP:
+      entity->y--;
+      entity->subY = ENTITY_MOVE_SUBPIXEL;
+      break;
+    case ENTITY_DIR_DOWN:
+      entity->y++;
+      entity->subY = -ENTITY_MOVE_SUBPIXEL;
+      break;
+    case ENTITY_DIR_LEFT:
+      entity->x--;
+      entity->subX = ENTITY_MOVE_SUBPIXEL;
+      break;
+    case ENTITY_DIR_RIGHT:
+      entity->x++;
+      entity->subX = -ENTITY_MOVE_SUBPIXEL;
+      break;
+    default:
+      assertUnreachable("Invalid entity direction");
+  }
+}
+
+bool_t entityIsWalking(const entity_t *entity) {
+  assertNotNull(entity, "Entity cannot be NULL");
+  return (entity->subX != 0 || entity->subY != 0);
+}
+
 entity_t * entityGetAt(const uint8_t x, const uint8_t y) {
   entity_t *e = ENTITIES;
   do {