WARNING: This plugin is barebones and supports a limited set of features. Please go read more about kajiya for context. It is an experiment in Rust rendering, not intended to be a fully featured renderer.

Yes, you can visualize some bevy entities in ray-traced glory, but don't expect much else for now; there is a finite number of meshes that can be instanced and meshes cannot be uninstanced yet. Expect some bugs and crashes!

Example

See bevy-kajiya-playground for basic usage of bevy and bevy-kajiya in a bevy app. You can fly around a simple scene with moving meshes in first person, manipulate the sun, and view a reflection of your player model in a mirror.

Usage

You must disable the default bevy renderer. Additionally, a patch is required for ray-tracing extensions. Put the following in your top-level Cargo.toml:

[dependencies]
bevy = { version = "0.6.0", default-features = false, features = ["bevy_winit"] }
bevy-kajiya = { path = "../path/to/bevy-kajiya" }

[patch.crates-io]
# Official ray-tracing extensions
rspirv = { git = "https://github.com/gfx-rs/rspirv.git", rev = "dae552c" }
spirv_headers = { git = "https://github.com/gfx-rs/rspirv.git", rev = "dae552c" }

kajiya does not support resizable windows yet. The window might be larger than anticipated due to the OS' DPI settings, so you may have to decrease the requested resolution. Make sure to use these window settings:

    .insert_resource(WindowDescriptor {
        width: 1920.,
        height: 1080.,
        vsync: false,
        resizable: false,
        ..Default::default()
    })

Add these plugins:

    .add_plugins(DefaultPlugins)
    .add_plugins(BevyKajiyaPlugins)

Scenes

You specify the scene to be loaded on startup with the KajiyaSceneDescriptor resource inserted in App::new(). The scene as specified by "my-scene" should be located in assets/scenes/my-scene.ron

    .insert_resource(KajiyaSceneDescriptor {
        scene_name: "my_scene".to_string(),
        ..Default::default()
    })

Scene Format Example

The renderer looks for all meshes in assets/meshes/. In this example, the mesh files should be located in assets/meshes/336_lrm/ and assets/meshes/floor/

(
    instances: [
        (
            position: (0, -0.001, 0),
            mesh: "336_lrm",
        ),
        (
            position: (0, 0, 0),
            mesh: "floor",
        ),
    ]
)

Meshes

You must run bake.cmd any time mesh assets have been modified (or if first time building). Adding new meshes requires adding a line in bake.cmd:

%BAKE% --scene "assets/meshes/my_mesh/scene.gltf" --scale 1.0 -o my_mesh

Then you can spawn the mesh with:

    commands.spawn_bundle(KajiyaMeshInstanceBundle {
        mesh_instance: KajiyaMeshInstance { 
            mesh: KajiyaMesh::User("my_mesh".to_string()),
        },
        transform: Transform::from_translation(Vec3::new(0.0, 0.0, 0.0)),
        ..Default::default()
    });

Camera

You must spawn exactly one camera. Put this in your setup system:

    commands.spawn_bundle(KajiyaCameraBundle {
        camera: KajiyaCamera {
            aspect_ratio: window.requested_width() / window.requested_height(),
            ..Default::default()
        },
        ..Default::default()
    })