🕊️💡 bevy-kajiya

A bevy plugin that integrates the kajiya renderer with bevy

WARNING: This plugin is barebones and supports a limited set of features. Please go read more about kajiya for context and dependencies you may need for your system. This plugin and kajiya are experimental, and using this in a production environment is not recommended!

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 removed from memory on despawn. Expect some bugs and crashes!

Example

Included in examples/ is a simple bevy app demonstrating using the kajiya renderer with bevy systems, including camera controls and mesh instance transform manipulation. From this repo, execute

cargo run --example view

Usage

Make sure to clone kajiya. It is recommended to to point this project to this commit of kajiya, and that your file structure looks like

.
└── my_project/
    ├── bevy-kajiya/
    └── kajiya/

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-kajiya = { git = "https://github.com/seabassjh/bevy-kajiya" }
bevy = { version = "0.8.0", default-features = false, features = ["bevy_winit"] }

[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" }

Lastly, the .dll and .so libraries will need to be copied to the root of your bevy project, if you plan to pull in this crate as an external dependency.

Bevy Setup

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.

1. Make sure to use these window settings (resolution can be changed):

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

2. Configure kajiya renderer user settings and pass them to the plugin:

    .insert_resource(KajiyaDescriptor::default())

3. Lastly, add these plugins:

    .add_plugins(DefaultPlugins)
    .add_plugins(BevyKajiyaPlugins)

Meshes

Meshes are loaded at runtime from their gltf source file, and hot-reloading is now supported by default!

    commands.spawn_bundle(KajiyaMeshInstanceBundle {
        mesh_instance: KajiyaMeshInstance {
            mesh: "floor".to_string(),
            ..Default::default()
        },
        ..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(),
            ..KajiyaCamera::default()
        },
        ..Default::default()
    });

Contribution

Contributions are welcomed :) Long term plan is to replace the KajiyaBlah render and mesh types with bevy renderer-compatible types.

Contributions shall comply with the Rust standard licensing model (MIT OR Apache 2.0) and therefore be dual licensed as described below, without any additional terms or conditions:

License

This contribution is dual licensed under either

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)