shrubbery

Shrubbery is a procedural voxel generation library for rust projects. Features:

• Serializable shaping logic
• Built in space colonization implementation
• Deterministic generation

Integrate into any game

This is my voxel game, utilizing shrubbery.ron assets.

Example: "editor"

The editor example code, can preview ANY shrubbery.ron asset.

Example code: minimal

fn main() {
    let seed = rand::random();
    let shrubbery_settings = shrubbery_settings();
    let mut generator = ShrubberyGenerator::generate(seed, &shrubbery_settings);
    let voxels = generator.voxelize();
}

How a shrubbery is designed

Here is all shaping features:

• Branch (3D lines with start + end point)
• Shape::Sphere, spawned on branch end points
• Shape::ConiferWhorl, segmented 4-star shape, placed along a branch's start-end point. Perfect for fir/pine trees.
• Shape::Starleaf, a 4-star shape.

You construct building steps, here is an example based upon: "Assets/oak.shrubbery.ron"

(
    build_steps: [
        SpawnRoot(( id: AssignId(0), )),
        Grow((
            times: Value(7),
            length: Range(3.0, 5.0),
            thickness: IterationScale(min: Value(3.0), max: Value(1.0),),
            filter: (ignore_root: false),
        )),
        SpawnAttractors((
            location: FromBranch(()),
            shape: Cube((size_x: 25.0, size_y: 20.0, size_z: 25.0)),
            attractor_spacing: AttractorSpacing(attractor_spacing: 6.0, jitter_ratio: 1.0),
        )),
        // spawn new branches using space colonization to fill the attractor space
        Grow((
            times: Value(3),
            dir: Attractor(()),
            length: Value(8.0),
            filter: (id: Target(1)),
        )),
        Shape((
            shape: Sphere(radius: Value(6.0)),
            voxel: Value(Solid(VoxelMapping(name: "leaf_orange"))),
            filter: (iteration: Greater(0)),
    ],
)

Feature flags

Feature	Default	Description
serde	✓	Serialization for settings and voxel definitions (RON, etc.)
bevy	✓	Bevy integration: shrubbery.ron asset loader, plugin, debug draw. Implies serde and pulls in ron

Bevy support table

bevy	shrubbery
0.19	0.3
0.17.3	0.2

Testing

cargo test

Determinism is verified with golden hashes: tests/golden_hashes/*.golden.ron record the expected voxel-output hash for every asset in assets/shrubbery/ at a fixed set of seeds. The tests discover assets automatically — there is no hard-coded list.

If you intentionally change generation behavior or add a new asset, the golden hash test will fail until you regenerate and commit the goldens:

cargo test --test generate_golden_hashes -- --ignored --nocapture

License

Shrubbery is free and open source! All code in this repository is dual-licensed under either:

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

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.