Configure collider as a child entity/component

[wentao]

Here is the use case I'm facing: I have a blender exported glb scene where it contains a rendering object and collider object with different names. Let's call them view and collider. The collider object is much simpler but wraps the view object very well.

After loading the scene into bevy, I can use the following code to hide the collider from rendering

commands
        .spawn((
            HookedSceneBundle {
                scene: SceneBundle {
                    transform: ...
                    scene: ...
                    ..default()
                },
                hook: SceneHook::new(|entity, cmds| {
                    let name = entity.get::<Name>().map(|t| t.as_str());
                    match name {
                        Some("collider") => cmds
                            .insert(Visibility::Hidden)
                            .insert(TagCollider),
                        _ => cmds,
                    };
                }),
            },
            RigidBody::Kinematic,

The TagCollider component will be processed async in another system where we can generate the Collider from the mesh

let collider = Collider::trimesh_from_mesh(meshes.get(mesh.id()).unwrap()).unwrap();
commands.entity(entity).remove::<TagCollider>().insert(collider);

This works fine and I can detect collision events between the colliders correct. However, the Collider is attached to a descendant entity of the root entity I added during the scene loading phase.

Is there anyway to configure collision event to point at RigidBody entity (the root), rather than the Collider entity? I used bevy_rapid3d previously and the collision events generated there always points RigidBody entity instead of Collider entity.

[Jondolf]

Child colliders have a ColliderParent component that points to the Entity of the root RigidBody. That should work as a workaround for now.

It would be straightforward to change collision events to always point to the rigid body entity, and I might change the default to that... but pointing to the Collider entity can also have use cases. Like if you had a sensor collider for ground detection as the child of a Player entity, you might want to get collisions specifically for the collider to know that you hit the ground and not something else.

One option would be to make collisions store both the rigid body entity and the collider entity. This would make both use cases viable.

[wentao]

Thank you for quick response!

ColliderParent works pretty well for my use case. Having collisions store both regid body entity and collider entity sounds even better.