Task 003: WASM Bridge and TS Bindings

Status: DONE (2026-02-23)

Goal

Expose a minimal stable API from the Rust core library to TypeScript via WASM. Verify with round-trip tests.

Depends on

• Task 002 (Rust core types)

Implementation Notes

Design Decision (Codex-reviewed)

• Approach A: Flat f64 API — functions take/return raw f64, newtype wrapping at the WASM boundary
• Separate solar-line-wasm crate depends on solar-line-core
• Built with wasm-pack --target nodejs for Node tests; --target web for browser reports
• Constants exported as grouped getters (get_mu_constants, etc.) not individual functions
• Compound results: arrays for tuples (hohmann_transfer_dv → Float64Array), objects for named fields (solve_kepler → {eccentric_anomaly, iterations, residual})

Files Added/Changed

• crates/solar-line-wasm/ — new crate (Cargo.toml + src/lib.rs)

- Dependencies: wasm-bindgen, serde, serde-wasm-bindgen

- 8 native Rust tests

• ts/src/wasm.test.ts — 16 round-trip tests verifying WASM matches TS and reference values
• .github/workflows/ci.yml — updated to build WASM before TS tests
• .gitignore — added ts/pkg/ (generated WASM output)

Exported WASM API

• vis_viva(mu, r, a) → f64
• hohmann_transfer_dv(mu, r1, r2) → Float64Array
• orbital_period(mu, a) → f64
• specific_energy(mu, a) → f64
• specific_angular_momentum(mu, a, e) → f64
• solve_kepler(M, e) → {eccentric_anomaly, iterations, residual}
• mean_to_true_anomaly(M, e) → f64
• true_to_mean_anomaly(nu, e) → f64
• eccentric_to_true_anomaly(E, e) → f64
• true_to_eccentric_anomaly(nu, e) → f64
• eccentric_to_mean_anomaly(E, e) → f64
• mean_motion(mu, a) → f64
• propagate_mean_anomaly(m0, n, dt) → f64
• get_mu_constants() → {sun, mercury, venus, earth, mars, jupiter, saturn, uranus, neptune}
• get_orbit_radius_constants() → {mercury, venus, earth, mars, jupiter, saturn}
• get_reference_orbit_constants() → {earth_radius, leo_radius, geo_radius}

Test Coverage

• 37 Rust core tests + 8 WASM crate tests + 19 TypeScript tests (16 WASM round-trip) = 64 total