Realtime Path Tracer for Bevy

bevy-hikari is an implementation of global illumination for Bevy.

After Bevy releasing 0.8, the plugin moves to deferred hybrid path tracing. For the old version (0.1.x) which uses voxel cone tracing with anisotropic mip-mapping, please check the bevy-0.6 branch.

Bevy Version Support

| bevy | bevy-hikari | | ------ | ------------- | | 0.6 | 0.1 | | 0.8 | 0.2 |

Progress

[x] Extraction and preparation of mesh assets and instances
[x] G-Buffer generation
[x] 2-bounce path tracing
[x] Next event estimation
[x] ReSTIR: Temporal sample reuse
[ ] ReSTIR: Spatial sample reuse
[ ] Spatiotemporal filtering
[ ] Hardware ray tracing (upstream related)

Basic Usage

Add HikariPlugin to your App after PbrPlugin
Setup the scene with a directional light
Set your camera's camera_render_graph to CameraRenderGraph::new(bevy_hikari::graph::NAME)

```rust use bevy::{pbr::PbrPlugin, prelude::, render::camera::CameraRenderGraph}; use bevy_hikari::prelude::; use std::f32::consts::PI;

fn main() { App::new() .addplugins(DefaultPlugins) .addplugin(PbrPlugin) // Add Hikari after PBR .addplugin(HikariPlugin) .addstartup_system(setup) .run(); }

fn setup( mut commands: Commands, mut meshes: ResMut>, mut materials: ResMut>, assetserver: Res, ) { // Plane commands.spawnbundle(PbrBundle { mesh: meshes.add(Mesh::from(shape::Plane { size: 5.0 })), material: materials.add(Color::rgb(0.3, 0.5, 0.3).into()), ..default() }); // Cube commands.spawnbundle(PbrBundle { mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })), material: materials.add(Color::rgb(0.8, 0.7, 0.6).into()), transform: Transform::from_xyz(0.0, 0.5, 0.0), ..default() });

// Only directional light is supported
commands.spawn_bundle(DirectionalLightBundle {
    directional_light: DirectionalLight {
        illuminance: 10000.0,
        ..Default::default()
    },
    transform: Transform {
        translation: Vec3::new(0.0, 5.0, 0.0),
        rotation: Quat::from_euler(EulerRot::XYZ, -PI / 4.0, PI / 4.0, 0.0),
        ..Default::default()
    },
    ..Default::default()
});

// Camera
commands.spawn_bundle(Camera3dBundle {
    // Set the camera's render graph to Hikari's
    camera_render_graph: CameraRenderGraph::new(bevy_hikari::graph::NAME),
    transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
    ..Default::default()
});

} ```