Why aren't `Fill` and `Stroke` housed in `ShapeBundle`?

[akappel]

Obviously this is already merged (via #198) and out in the wild, but I'm trying to understand why Fill and Stroke were pulled out of ShapeBundle? The idea of making them components was a good one, and the updated ergonomics of GeometryBuilder seems sound. But now I have two extra components on my top-level bundle that weren't needed previously, and are only useful in the context of the ShapeBundle.

As an example, my PinballBundle goes from:

#[derive(Component)]
pub struct Pinball;

#[derive(Bundle)]
pub struct PinballBundle {
    pinball: Pinball,
    rigidbody: RigidBody,
    collider: Collider,
    friction: Friction,
    #[bundle]
    shape_bundle: ShapeBundle,
}

to:

#[derive(Component)]
pub struct Pinball;

#[derive(Bundle)]
pub struct PinballBundle {
    pinball: Pinball,
    rigidbody: RigidBody,
    collider: Collider,
    friction: Friction,
    #[bundle]
    shape_bundle: ShapeBundle,
    fill: Fill,
    stroke: Stroke,
}

Not a huge deal, just liked having it all packaged under ShapeBundle. Since I use ShapeBundle in other places as well, it feels like I'll need to create an intermediary bundle to join them back together.

[Nilirad]

It's because you may not always want to have both components at the same time, and Bevy does not have bundles with optional components.

We may add a different bundle for each draw mode, but I have to think about it.

• For optional components, see bevyengine/bevy#2157

[akappel]

Ah okay, makes sense. Thanks for the background! A bundle for each draw mode sounds promising, but for now I'll just create that intermediary bundle with both 👍 Thanks!