Interactivity

Lunex implements its interactivity on top of Bevy_mod_picking. If you need more control over interactions, consider researching this crate.

This crate allows us to detect mouse clicks, hovers, drags, etc.

Requirements

• Please note that Cursor2d MUST be spawned for any picking to work.

• UiLunexPickingPlugin must be added (Part of UiDefaultPlugins but not part of UiMinimalPlugins)

• DefaultPickingPlugins.build().disable::<InputPlugin>() version of picking plugins must also be added (Part of UiDefaultPlugins but not part of UiMinimalPlugins)

Getting started

Interactivity is achieved by utilizing Events and Systems. Lunex provides several components to simplify the process. First, ensure your entity is pickable by adding PickableBundle for entities with sprites or meshes, and UiZoneBundle for entities without sprite or meshes.

Pay attention to DEPTH of entities (Not just UI entities), because if they overlap your pickable node, they will block all picking events. To avoid that, you can add Pickable::IGNORE component to any entity that might overlap your node.

#![allow(unused)]
fn main() {
// Make it non-obsructable for hit checking (mouse detection)
Pickable::IGNORE,
}

To check for mouse clicks, listen to UiClickEvent in your systems using the following code:

#![allow(unused)]
fn main() {
// Here we can listen to UiClick events that hold entity ID, then retrieve that entity from our query
fn button_click_system(mut events: EventReader<UiClickEvent>, query: Query<&CustomButton>) {
    // Iterate over all events
    for event in events.read() {
        // Get our entity
        if let Ok(button) = query.get(event.target) {
            // Process our button click
            info!("Pressed button: {}", button.text);
        }
    }
}
}

Note that UiClickEvent is NOT emitted automatically; you need to add a component to emit this event when Pointer<Down> is triggered, if you decide to make your own components.

#![allow(unused)]
fn main() {
// If we click on this node, it will emmit UiClick event on itself
UiClickEmitter::SELF,

// If we click on this node, it will emmit UiClick event from specified entity
UiClickEmitter::new(entity),
}

This component is really useful when creating complex components. You want UiClickEvent to be emmited from the top entity in a component, so users can listen to them. This component allows you to do exactly that.

Another components that you might find useful are:

#![allow(unused)]
fn main() {
// If it detects UiClick event for this entity it will despawn the specified entity, great for despawning routes
OnUiClickDespawn::new(entity),

// If it detects UiClick event for this entity it will run the closure, great for spawning routes
OnUiClickCommands::new(|commands| { commands.spawn(MyRoute); })
}