Function bevy_mod_picking::mesh_events_system

pub fn mesh_events_system(
    mouse_button_input: Res<'_, Input<MouseButton>>, 
    touches_input: Res<'_, Touches>, 
    picking_events: EventWriter<'_, '_, PickingEvent>, 
    hover_query: Query<'_, '_, (Entity, &Hover, ChangeTrackers<Hover>), (Changed<Hover>, With<PickableMesh>)>, 
    selection_query: Query<'_, '_, (Entity, &Selection, ChangeTrackers<Selection>), (Changed<Selection>, With<PickableMesh>)>, 
    click_query: Query<'_, '_, (Entity, &Hover)>
)

Looks for changes in selection or hover state, and sends the appropriate events