I'm playing around with Forge2d on Flutter Flame and created a Ninja which throws Kanuies (a character shooting bullets basically). If I create Kanuies and the Ninja separately then add them separately to the game world, all will be fine. However, I want the Ninja class to be responsible for login for throwing the Kanui. So I was wondering what is the right way to add a bullet component to a character component in Forge2d.

In my current code, inside Ninja Class, if I call add(Kanui) there will be no graphics shown about Kanuie NOT even with debugMode=true . However, if use addToParrent(Kanui) it will be fine again.

Below is the link to my code. Please have a look and suggest corrections. I'll provide some snippets here as well.

https://github.com/bmd007/flame_playground/blob/154cc0a9a99cc4bd5732e8d0c94bfa38093b0298/lib/my_girl.dart#L134

Ninja Class:

class MyGirl extends BodyComponent {

  late SpriteAnimationComponent component;
  Queue<MyGirlKanui> kanuies = Queue<MyGirlKanui>();

  @override
  Future<void> onl oad() async {
    await super.onLoad();
    idleAnimation = await gameRef.loadSpriteAnimation("red_girl/idle_spriteSheet.png", idleAnimationData);

    component = SpriteAnimationComponent()
      ..animation = idleAnimation
      ..size = Vector2.all(6)
      ..anchor = Anchor.center;
    add(component);

    kanuies.add(MyGirlKanui(initialPosition));
  }


  @override
  Body createBody() {
    final shape = PolygonShape()..setAsBoxXY(3, 3);
    final fixtureDefinition = FixtureDef(shape, density: 2, restitution: 0.1, friction: 2);
    final bodyDefinition = BodyDef(position: initialPosition, type: BodyType.dynamic)..fixedRotation = true;
    return world.createBody(bodyDefinition)..createFixture(fixtureDefinition);
  }

  throwKanui() async {
    if (kanuies.isNotEmpty) {
      var kanui = kanuies.removeFirst();
      // await parent?.add(kanui);
      await add(kanui);
      kanui.component.position = component.position;
      kanui.body.linearVelocity.x = 30;
    }
  }

I call the throw method when a UI button is pressed.

CodePudding user response：

In Forge2D you shouldn't add any bodies as children to other components. You can add the HasGameRef<Forge2DGame> mixin to the component and then you can add the bullets directly to the game. Also don't forget to put the body of the bullet to isBullet = true if the "bullet" is moving very fast, otherwise you could end up with tunneling (where the body passes through the object that it is supposed to hit).