🐕 Bevy Keith

2D graphic library inspired by Piet (📦 piet) for the Bevy game engine.

Currently a purely immediate-mode library (the ), but with future plans to explore partial retaining to reduce CPU usage.

Usage

Add the KeithPlugin to your Bevy app:

App::default()
    .add_plugins(DefaultPlugins)
    .add_plugin(KeithPlugin);

Add a Canvas component where you want to draw. If you add the Canvas on the same Entity as an OrthographicProjection component, then the canvas automatically resizes to the full orthographic camera area.

// Only for initial setup, or if controlled manually
let mut canvas = Canvas::new(Rect {
    min: Vec2::splat(-400.),
    max: Vec2::splat(100.),
});

// Optionally clear the canvas with a given color before drawing
canvas.set_background_color(Some(Color::BEIGE));

// Spawn on the same Entity as an OrthographicProjection for auto-resize
commands
    .spawn_bundle(Camera2dBundle::default())
    .insert(canvas);

Draw something on the Canvas via a RenderContext:

fn run(mut query: Query<&mut Canvas>) {
    let mut canvas = query.single_mut();
    canvas.clear();

    let mut ctx = canvas.render_context();

    // Draw a filled rectangle
    let brush = ctx.solid_brush(Color::PINK);
    let rect = Rect {
        min: Vec2::ZERO,
        max: Vec2::splat(50.),
    };
    ctx.fill(rect, &brush);

    // Draw a text
    let text = ctx
        .new_layout("Hello World!")
        .color(Color::ORANGE_RED)
        .font(...)
        .font_size(24.)
        .build();
    ctx.draw_text(text, Vec2::ZERO);

    // Draw a textured rectangle
    let rect = Rect {
        min: Vec2::new(100., 150.),
        max: Vec2::new(116., 166.),
    };
    ctx.draw_image(rect, my_res.image.clone());

    // Draw some lines
    let brush = ctx.solid_brush(Color::GREEN);
    for i in 0..=10 {
        ctx.line(Vec2::new(-200.5, 0.5 + i as f32 * 15.), Vec2::new(0.5, 0.5 + i as f32 * 40.), &brush, 1. + i as f32);
    }
}