`PointerDrag` component
A PointerDrag component would be convenient for checking if a certain pointer is dragging something when you're dealing with complex logic.
Maybe it can look something like this:
#[derive(Component, Deref)]
struct PointerDrag(Option<Entity>);
It will contain Some(Entity) when the pointer is currently dragging an entity.
This already exists in the form of events and event listeners. You could create your own special purpose component for this purpose if you want some other behavior.
https://docs.rs/bevy_mod_picking/latest/bevy_mod_picking/events/struct.Drag.html https://github.com/aevyrie/bevy_mod_picking/blob/main/examples/drag_and_drop.rs
I'm not sure if we want to add components for every type of event. This would also need to be a Vec, as a pointer can be dragging multiple entities at a time.