`mesh_picking` not updating when mesh data changes, bug or intended?

[ncorbin786]

Bevy version

0.15.3

What you did

Might be a bug with mesh_picking. I noticed that when I adjusted the vertex positions on a Plane3d in real time the Trigger<Pointer<Click>> events would still fire, but only based on the dimensions of the initial mesh.

The updates I made to the Mesh3d vertex positions wouldn't affect it. Visually I could see the new mesh was larger, but if I clicked anywhere in those zones nothing happened. I had to click the original position to get it to fire.

I was using mesh.insert_attribute(Mesh::ATTRIBUTE_POSITION, new_positions.clone()); to adjust the vertex positions.

What went wrong

• Adjusting Mesh3d vertex positions does not update mesh_picking

Additional information

I found I was able to get it to work, as intended, after updating the vertex position by removing the Aabb component and re-adding it:

                    // Update the AABB to refresh raycasting
                    commands.entity(parent.get()).remove::<Aabb>();
                    commands.entity(parent.get()).insert(mesh.compute_aabb().unwrap());

[alice-i-cecile]

This is a bug. We need to be using asset changed detection. There's a new system param for it.

[notmd]

Related #7971

[StudioLE]

This has been bugging me for a while as well. It also occurs if you replace the Mesh3d with a new Mesh

Manually re-computing the Aabb does fix it.

Condensed workaround:

    /// Update the mesh geometry when the spline changes.
    fn on_spline_changed(
        mut events: EventReader<SplineChanged>,
        mut surfaces: Query<(&mut Mesh3d, &mut Aabb)>,
        mut meshes: ResMut<Assets<Mesh>>,
    ) {
        for event in events.read() {
            for (mut mesh_3d, mut aabb) in &mut surfaces {
                let mesh: Mesh = create_mesh();
                *aabb = mesh.compute_aabb().expect("Should be able to compute AABB");
                *mesh_3d = Mesh3d(meshes.add(mesh));
            }
        }
    }

[alice-i-cecile]

Ah, so the same bug that we're getting with animated meshes and their AABB: #4971.