Sprite Component exits screen in flame flutter - flutter

Question

I am completely new to flame and game development, I know with camera and viewpoint you can control the components but my component exits the screen and I don't know how to stop it from moving forward when it reaches the screen end.
Any idea how?

Answer 1

You don't want to control how your SpriteComponents move with the camera, the camera moves what you are looking at in the "world" and you want to move your component in the world.
If you don't move the camera then the solution can be to just look at whether the component is still within the screen by using a ScreenHitbox and the CollisionDetection system. (You could also just check the bounding box against the screen size).
Something like this, where it just moves back to the position it was in before colliding with the screen, should work:
class YourGame extends FlameGame with HasCollisionDetection {
Future<void> onLoad async {
add(ScreenHitbox());
}
...
}
class YourComponent extends SpriteComponent {
final Vector2 lastPosition = Vector2.zero();
#override
Future<void> onLoad() async {
...
// Adds a hitbox that covers the size of your component,
// so make sure that you have the size set.
add(RectangleHitbox());
}
...
#override
void update(double dt) {
lastPosition.setFrom(position);
// Update your position etc here
}
#override
void onBeginCollision(Set<Vector2> intersectionPoints, PositionComponent other) {
position = lastPosition;
}
}