fizecks

A physics engine written in Rust.

Usage

use fizecks::{Body, BodyKind, Shape, Vec2, World};

let mut world = World::new();
world.gravity = Vec2::new(0.0, 300.0);

// Static floor.
world.add_body(
    Body::new(Shape::Rect { half_width: 200.0, half_height: 10.0 })
        .with_position(Vec2::new(400.0, 550.0))
        .with_kind(BodyKind::Static),
);

// Bouncing ball.
world.add_body(
    Body::new(Shape::Circle { radius: 20.0 })
        .with_position(Vec2::new(400.0, 100.0))
        .with_restitution(0.8),
);

// Step the simulation.
let dt = 1.0 / 120.0;
world.step(dt);

Demos

The examples are headless: each one steps a scene deterministically, records a frame per step into an in-memory framebuffer, encodes an animated GIF to out/<name>.gif, and opens it in your default image viewer.

cargo run --example bouncing_ball       # gravity & restitution
cargo run --example box_stack           # stacking & friction
cargo run --example pendulum            # revolute joint
cargo run --example ccd_bullet          # continuous collision (tunnelling)
cargo run --example sensor_trigger      # sensor enter/exit events
cargo run --example kinematic_platform  # kinematic body carrying a dynamic box
cargo run --example convex_pile         # convex polygons heaping in a bin
cargo run --example ray_casting         # ray query sweep with hit markers

Each example also asserts its final state, so a run that doesn't end in PASS signals a regression. The only extra dependency is the small, pure-Rust gif encoder, declared as a dev-dependency — the library crate itself has zero dependencies.

Tests

cargo test

Status

fizecks is a library crate. Behavior is verified through the integration tests in tests/ and demonstrated by the headless examples above — see ROADMAP.md for feature progress.