Rust bindings target in generate.mk

[Fedr]

Adds TARGET=rust to scripts/mrbind/generate.mk, the MeshLib side of MeshInspector/mrbind#54 (requested in #5910), plus examples, tests, CI, and the crate as a release asset.

generate.mk

make -f scripts/mrbind/generate.mk TARGET=rust

generates source/MeshLibRust/src (gitignored) from source/MeshLibC2/temp/interop_desc.json and runs cargo build on the crate. source/MeshLibRust/Cargo.toml and build.rs are committed (the generator doesn't emit them, per the mrbind review). Like TARGET=csharp, it needs TARGET=c to have run first. The CUDA sub-library is mapped to MeshLibC2Cuda with --imported-split-lib-name, same as for C#. --force-namespace MR puts the std:: container instantiations under mr:: too. Consumers of the crate get the C libraries' directory from MESHLIB_LIB_DIR, which build.rs reads and the build rule sets to the MeshLib build directory when it exists.

On the full MeshLib API the generator wraps 37764 functions (715 of them with raw C types, none skipped) and the crate compiles with no warnings. Classes get upcast_to_<base>() / downcasts from the C cast functions, std::function wrappers get from_fn(closure), and [[clang::lifetimebound]] becomes explicit lifetimes.

Examples

examples/rust-examples has MeshBoolean, MeshDecimate and MeshLoadSave, ported from the C examples. The boolean one, for comparison with MeshBoolean.dox.c:

let sphere1 = mr::make_uv_sphere(Some(1.0), Some(64), Some(64));
let mut sphere2 = sphere1.clone();
sphere2.transform(&mr::AffineXf3f::translation(&Vector3f {x: 0.7, y: 0.0, z: 0.0}), None);
let mut mapper = BooleanResultMapper::new();
let result = mr::boolean_6(&sphere1, &sphere2, BooleanOperation::Intersection, None, Some(&mut mapper), None);
if !result.valid() { return Err(format!("Failed to perform boolean: {}", result.error_string())); }
let faces_of_sphere1 = mapper.map_mr_face_bit_set(sphere1.topology().get_valid_faces(), MapObject::A);

Tests

source/MRTestRust ports all of MRTestC2 (28 files, 92 tests) to cargo test, one module per C test file, with the same inputs and expected numbers, plus one test with a progress callback made from a Rust closure (including cancelling through it). All pass on every CI job below, and locally against the MeshLib 3.1.4.297 NuGet libraries (one assertion, compute_per_face_normals_1, needs a newer library than that package).

CI

One Release job per OS and architecture runs .github/actions/build-rust-bindings: install Rust if missing (.github/actions/setup-rust, a minimal rustup toolchain in the runner's temp directory), generate and build the crate, build and run the examples and the tests against the freshly built C bindings. That's the GCC jobs on Ubuntu (22/24/26, x64 and arm64), the CMake jobs on Windows (x64 and arm64), and the vcpkg jobs on macOS (x64 and arm64).

The arm64 ubuntu22 job that already uploads the C# and Python binding sources also uploads the crate, and upload-distributions attaches it to the draft release as meshlib_<version>_rust_bindings.zip (Cargo.toml, build.rs, src; the C libraries come from the platform packages).
The generated src is byte-identical on all 10 jobs (verified by a temporary comparison job, https://github.com/MeshInspector/MeshLib/actions/runs/38567043688/job/115887156957), so one archive serves all platforms.

Docs

doxygen/general_pages/RustSetupGuide.md (linked from Getting Started and the navigation), and Rust tabs in the boolean, decimate and load/save example pages.

mrbind gitlink

thirdparty/mrbind is bumped to the head of the rust-generator branch so that mrbind_gen_rust gets built by the existing mrbind build steps on every platform. It must be re-bumped to the merge commit once mrbind#54 merges.

🤖 Generated with Claude Code

[Grantim]

We should at least put result package at draft releases

[Grantim]

should we upload from other platforms too?

[Fedr]

The crate is sources only, like the C# assembly: the same code on every platform (it references the C library by name, MeshLibC2, which the linker resolves to the .dll/.so/.dylib of the target), while the binaries come from the platform packages. So we publish one crate, and the new compare-rust-bindings job verifies on every run that all platforms generate the same one (8122de7, f45e593).

[Grantim]

should we mention Rust in public docs?

[Fedr]

Done in 5e35e44: a Rust setup guide (doxygen/general_pages/RustSetupGuide.md, linked from Getting Started and the navigation), and Rust tabs in the boolean, decimate and load/save example pages.