bevy_rich_text3d

Mesh based raster rich text implementation for bevy.

This crate is similar to bevy_text but aims to be more user friendly and powerful.

Unlike bevy_text, this crate renders text as a Mesh and an Image atlas. This not only works with StandardMaterial but also can be empowered by user defined shaders.

We render each glyph as a separate quad, meaning in shaders, we can easily manipulate individual glyphs for different effects. Additionally we support exporting specific values like glyph count, glyph position or user defined magic numbers via either uv1 or custom mesh attributes.

Add plugins:

app.add_plugins(Text3dPlugin{
    default_atlas_dimension: (1024, 1024),
    load_system_fonts: true,
    ..Default::default()
});

// Add fonts via the `LoadFonts` resource.
app.insert_resource(LoadFonts {
    font_paths: vec!["assets/roboto.ttf".to_owned()],
    font_directories: vec!["assets/fonts".to_owned()],
    ..Default::default()
});

Spawn a Text3d.

commands.spawn(
    Text3d::new("Hello, World!"),
    // Mesh2d also works
    Mesh3d::default(),
    MeshMaterial3d(materials.add(
        StandardMaterial {
            base_color_texture: Some(TextAtlas::DEFAULT_IMAGE.clone()),
            alpha_mode: AlphaMode::Blend,
            ..Default::default()
        }
    ))
)

Rich text can be created from a string using the Text3d::parse function. We support a straightforward syntax:

• {style:value}: equivalent to <style>value</style> in html.
• {value} (without :): parse as a dynamic value that can be fetched from the world.

See documentation on Text3d::parse for up-to-date syntax.

• cosmic_text

A minimal subset of Cosmic text is used for layout.

• tiny_skia

Used for tesselation.

• bevy

Bevy's asset system functions as an alternative to swash.

We store rendered glyphs inside a texture atlas in the component TextAtlasHandle. If you did not create a new one, all glyphs will be cached inside the same default texture, and you can use the convenient TextAtlas::DEFAULT_IMAGE as the image in your materials.

However, if you need more control over where your glyphs are stored, you can manually create a TextAtlas and Image alongside your Text3d, they can be managed the same way as other assets.

• How do I add fonts?

Add them to the LoadFonts resource before the app starts.

• Some characters are missing when text changes

You must add TouchTextMaterial*dPlugin to get around a change detection issue in bevy. This is a band-aid solution intended to be removed later as we wait for a fix upstream.

• Some glyphs are displaying as ▮▮▮▮

This means the placeholder glyphs for emojis are getting prioritized. You should either set the font family in Text3dStyling or set a default serif font in the plugin.

• How do I use this crate on wasm?

The easiest way to use this crate is to embed your fonts into the binary via include_bytes!, then add them to LoadFonts via font_embedded.

Licensed under either of

• 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)

at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.