Firefly

Firefly is an open-source, 2d lighting crate for the bevy game engine.

It's goal is to be a fully 2d lighting crate with features akin to the ones of more mature game engines, while keeping performance as high as possible and the minimizing the end-user API.

Firefly is still pretty early in development, with many features to be added still. However, there are already lot of cool stuff for you to play with or use for your games, if you wish to.

Short video showing off soft shadows and z-sorting:

https://github.com/user-attachments/assets/1984ef2a-0edd-4a40-93cb-a901057a9b74

Credit for the characters and assets to Kimberly and her upcoming game!

Usage

To use this crate, simply run cargo run bevy_firefly or add firefly to your Cargo.toml file.

You can see all the firely versions here.

Here is a basis example of integrating firefly into a bevy app:

use bevy::prelude::*;
use bevy_firefly::prelude::*;

fn main() {
  App:new()
    .add_plugins((DefaultPlugins, FireflyPlugin))
    .add_systems(Startup, setup)
    .run();
}

fn setup(mut commands: Commands) {
  commands.spawn((
    Camera2d,
    FireflyConfig::default()
  ));
     
  commands.spawn((
    PointLight2d {
      color: Color::srgb(1.0, 0.0, 0.0),
      range: 100.0,
      ..default()
    },
    Transform::default()
  ));
     
  commands.spawn((
    Occluder2d::circle(10.0),
    Transform::from_translation(vec3(0.0, 50.0, 0.0)),
  ));
}

Check out the examples and the crate documentation to learn more about using it.

Features

Some of the existing features are:

• Dynamic lights and occluders
• Point lights
• Round and polygonal occluders
• Soft shadows
• Occlusion z-sorting
• Occlusion sprite masking
• Transparent & colored occluders
• Light banding

Some of the currently planned features are:

• Normal maps
• Occluders casting sprite-based shadows
• Mulitple lightmaps
• Light textures

Feel free to open an issue if you want to request any specific features or report any bugs!

Bevy Compatibility

I'm planning to update to a newer bevy version soon, but I'm not currently working on it. If you want me to hurry, feel free to open an issue for it, and I'll try to prioritize it more :)

Alternatives

You can check out bevy_light_2d and bevy_lit. They were both a big inspiration when starting out with this crate!