manifold-rust

Pure Rust port of Manifold — a geometry library for 3D boolean operations on triangle meshes.

Part of the rust-apps suite — a collection of Rust graphics and geometry libraries by Lars Brubaker.

Status: Port in progress. See PORTING_PLAN.md for current phase.

What is Manifold?

Manifold is a high-performance C++ library for 3D solid modeling. It supports:

• Boolean operations (union, intersection, difference) on triangle meshes
• Mesh constructors (sphere, cube, cylinder, extrude, revolve)
• Cross-section (2D polygon) operations
• Smooth subdivision and SDF-based mesh generation
• Convex hull
• Minkowski sum/difference

This Rust port targets exact numerical match with the C++ implementation — same algorithms, same floating-point results, same triangle topology.

Why

MatterHackers uses 3D mesh boolean operations extensively in production for 3D printing workflows. A pure Rust implementation avoids FFI overhead and integrates cleanly with Rust tooling including WASM compilation.

Usage

// Coming soon — library is being ported incrementally

Demo

An interactive WASM demo will be available at https://larsbrubaker.github.io/manifold-rust/ once the port reaches a usable state.

Building

cargo build
cargo test

Restore the upstream C++ reference before doing exact-match validation:

git submodule update --init --recursive

Build and compare against the C++ reference with:

./validate-reference.ps1

You can also run a narrower validation slice by phase, for example:

./validate-reference.ps1 -Phase phase8

This configures and builds cpp-reference/manifold, runs the matching C++ reference tests, and then runs the corresponding Rust tests for the selected phase.

For the WASM demo:

cd demo
bun run build:wasm
bun run dev

Architecture

The port follows the C++ module structure:

Rust module	C++ source	Description
vec / linalg	linalg.h, vec.h	Vector math, linear algebra
polygon	polygon.cpp	2D polygon triangulation
impl	impl.cpp, impl.h	Core mesh data structure
constructors	constructors.cpp	Primitive mesh constructors
boolean3	boolean3.cpp	3D boolean operations
boolean_result	boolean_result.cpp	Boolean output assembly
csg_tree	csg_tree.cpp	CSG tree evaluation
edge_op	edge_op.cpp	Edge manipulation
face_op	face_op.cpp	Face manipulation
smoothing	smoothing.cpp	Smooth normals and subdivision
subdivision	subdivision.cpp	Mesh subdivision
properties	properties.cpp	Mesh properties
sdf	sdf.cpp	SDF-based mesh generation
quickhull	quickhull.cpp	Convex hull
minkowski	minkowski.cpp	Minkowski operations
cross_section	cross_section/	2D cross section

License

Apache-2.0 — matching the original Manifold library.

Credits

• Emmett Lalish — Author of the original Manifold library.
• Lars Brubaker — Port author.
• MatterHackers — Sponsor.