gdrr2bp-wasm

WebAssembly build of JeroenGar/gdrr-2bp — a goal-driven ruin & recreate heuristic for the 2D guillotine bin-packing / nesting problem (variable-sized bins, optional 90° rotation, guillotine cuts) — with a small typed TypeScript wrapper.

Install

npm install @archiyou/gdrr2bp-wasm

Layout

src/             vendored gdrr-2bp source + the wasm `solve()` entry point (lib.rs)
ts/BinPacker.ts  the typed BinPacker class + public types and wire mapping
ts/index.ts      barrel re-export
pkg/             generated wasm + JS/TS bindings (built by build.sh)
examples/        sample instance + config
tests/smoke.rs   native end-to-end test
build.sh         wasm-pack build script

Building

rustup target add wasm32-unknown-unknown   # once
cargo install wasm-pack                     # once
./build.sh

./build.sh runs wasm-pack build --target bundler and writes pkg/.

Usage (TypeScript)

import { BinPacker, type Instance } from '@archiyou/gdrr2bp-wasm';

// 1. Load the wasm (separate, awaited step)
const bp = await new BinPacker().init();

// 2. Solve — plain camelCase objects, no JSON wrangling
const instance: Instance = {
  name: 'demo',
  sheets: [{ length: 10, height: 10, cost: 100 }],   // stock omitted = unlimited
  parts:  [{ length: 5, height: 9, demand: 1, value: 45 }],
};

const solution = bp.solve(instance, { maxRunTime: 2 }); // seconds; single-threaded
console.log(solution.stats.usagePct, solution.patterns);

solve(instance, options) applies sensible defaults for any option you omit; only maxRunTime / maxRRIterations have no default (see note below). The returned Solution is fully camelCase: patterns[].sheet, patterns[].root (a CuttingNode tree), stats.usagePct, etc.

For the raw OR-Datasets wire format there is an escape hatch: bp.solveRaw(instanceJson, configJson): string.

Bound your runs. Set maxRunTime (seconds) and/or maxRRIterations. With neither set the solver runs until the optimum's minimum material limit is reached, which may be effectively unbounded for large instances.

Differences from upstream

This is a single-threaded port. The following changes were made to the vendored source (each marked // wasm port: in the code):

• std::time::Instant → web_time::Instant (std Instant panics on wasm).
• Dropped the mimalloc global allocator and the ctrlc handler (no wasm support).
• The multi-threaded monitor is bypassed; the lahc loop enforces maxRunTime directly. nThreads from the config is ignored.
• Logging macros write to console.log instead of stdout.
• getrandom uses the wasm_js backend (see .cargo/config.toml).

Upstream algorithm, IO format and results are otherwise unchanged.