State Machines

Interact with the Rive State Machine in Bevy

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For more information on Rive State Machines see the respective runtime and editor documentation.

Reading/Writing Inputs

Imports needed:

use rive_bevy::{
    events::{self, InputValue},
    RivePlugin, RiveStateMachine, SceneTarget, SpriteEntity, StateMachine,
};

The following code demonstrates reading and updating a Boolean state machine input.

Number and Trigger inputs can be accessed using get_number and get_trigger respectively.

fn update_state_machine_system(
    kbd: Res<Input<KeyCode>>,
    query: Query<(Entity, &mut RiveStateMachine)>,
) {
    if kbd.just_pressed(KeyCode::Return) {
        // Get the State Machine and its Entity
        let (_, state_machine) = query.get_single().expect("State machine not found");

        // Read the current value of an input
        let center_hover_current = state_machine.get_bool("centerHover").unwrap().get();

        // Update the input
        state_machine
            .get_bool("centerHover")
            .unwrap()
            .set(!center_hover_current);
    }
}

Alternatively, you can update an input using Bevy's EventWriter:

fn update_state_machine_system(
    kbd: Res<Input<KeyCode>>,
    query: Query<(Entity, &RiveStateMachine)>,
    mut input_events: EventWriter<events::Input>,
) {
    if kbd.just_pressed(KeyCode::Return) {
        // Get the State Machine and its Entity
        let (entity, _) = query.get_single().expect("State machine not found");

        // Send a new value to the input using Bevy events.
        input_events.send(events::Input {
            state_machine: entity,
            name: "shoot".into(), // name of the input
            value: events::InputValue::Trigger,
        });
    }
}

Additional Resources

• Rive Bevy inputs example