Expand description

About

A fully-featured set of tools for managing abilities in Bevy. This crate is meant to be used with Leafwing Input Manager, which converts inputs into actions.

Some of those actions will be abilities! Abilities are intended for gameplay use, and follow complex but relatively standardized logic about how they might be used.

use bevy::prelude::*;
use leafwing_abilities::prelude::*;
use leafwing_input_manager::prelude::*;

// We're modelling https://leagueoflegends.fandom.com/wiki/Zyra/LoL
// to show off this crate's features!
#[derive(Actionlike, Abilitylike, Clone, Copy, PartialEq)]
pub enum ZyraAbility {
    GardenOfThorns,
    DeadlySpines,
    RampantGrowth,
    GraspingRoots,
    Stranglethorns,
}

impl ZyraAbility {
    fn input_map() -> InputMap<ZyraAbility> {
        use ZyraAbility::*;

        // We can use this `new` idiom, which accepts an iterator of pairs
        InputMap::new([
            (KeyCode::Q, DeadlySpines),
            (KeyCode::W, RampantGrowth),
            (KeyCode::E, GraspingRoots),
            (KeyCode::R, Stranglethorns),
        ])
    }

    // This match pattern is super useful to be sure you've defined an attribute for every variant
    fn cooldown(&self) -> Cooldown {
        use ZyraAbility::*;

        let seconds: f32 = match *self {
            GardenOfThorns => 13.0,
            DeadlySpines => 7.0,
            RampantGrowth => 18.0,
            GraspingRoots => 12.0,
            Stranglethorns => 110.0,
        };

        Cooldown::from_secs(seconds)
    }

    fn cooldowns() -> CooldownState<ZyraAbility> {
        let mut cooldowns = CooldownState::default();

        // Now, we can loop over all the variants to populate our struct
        for ability in ZyraAbility::variants() {
            cooldowns.set(ability, ability.cooldown());
        }

        cooldowns
    }

    fn charges() -> ChargeState<ZyraAbility> {
        // The builder API can be very convenient when you only need to set a couple of values
        ChargeState::default()
            .set(ZyraAbility::RampantGrowth, Charges::replenish_one(2))
            .build()
    }
}

/// Marker component for this champion
#[derive(Component)]
struct Zyra;

#[derive(Bundle)]
struct ZyraBundle {
    champion: Zyra,
    #[bundle]
    input_manager_bundle: InputManagerBundle<ZyraAbility>,
    #[bundle]
    abilities_bundle: AbilitiesBundle<ZyraAbility>,
}

impl Default for ZyraBundle {
    fn default() -> Self {
        ZyraBundle {
            champion: Zyra,
            input_manager_bundle: InputManagerBundle::<ZyraAbility> {
                input_map: ZyraAbility::input_map(),
                ..default()
            },
            abilities_bundle: AbilitiesBundle::<ZyraAbility> {
                cooldowns: ZyraAbility::cooldowns(),
                charges: ZyraAbility::charges(),
            },
        }
    }
}

Features

  • track and automatically tick cooldowns
  • store multiple charges of abilities
  • Leafwing Studio’s trademark #[deny(missing_docs)]

Planned:

  • resource management (health, mana, energy etc)
  • damage
  • cast times
  • range checking

Modules

Charges are “uses of an action”. Actions may only be used if at least one charge is available.
Cooldowns tick down until actions are ready to be used.
Contains main plugin exported by this crate.
Everything you need to get started
The systems that power each InputManagerPlugin.

Structs

This [Bundle] allows entities to manage their Abilitylike actions effectively.
A custom WorldQuery type that fetches all ability relevant data for you.

Traits

Allows a type to be used as a gameplay action in an input-agnostic fashion

Functions

Checks if a Charges, Cooldown pair associated with an action is ready to use.
Triggers an implicit action, depleting a charge if available.

Derive Macros