CadConvert 0.1.0

CadConvert

Parasolid (.x_t) and STEP (.stp) to glTF 2.0 or USDZ. Reads the B-Rep, tessellates it watertight, and writes a mesh with materials — no CAD kernel to install.

using CadConvert;

var result = CadConverter.Convert("housing.x_t", "housing.glb");
// The output's extension chooses the container: .glb or .usdz.

Console.WriteLine($"{result.Bodies} bodies, {result.Triangles:N0} triangles");
foreach (var warning in result.Warnings)
    Console.WriteLine($"warning: {warning}");

Defaults

The mesh is held to 0.04 % of the model's own diagonal and 8° between adjacent facet normals. Both are needed: a distance alone is satisfied by almost no subdivision on a small radius, which is how a 1 mm hole becomes a triangle. SagMillimetres and AngleDegrees are null by default and mean "the converter's own"; setting a distance also turns the relative reading off.

MeshTarget.Lean, the default, encodes normals a byte a component and leaves every vertex exactly where it was computed. Compact also puts positions on each mesh's own 16-bit grid — about a quarter smaller again, and it collapses the mesh's finest slivers, so it is for delivery rather than for modelling with. Plain compresses nothing.

Warnings are not failures

A call that returns normally produced a file. Warnings lists what the readers or the tessellator could not do — faces that produced no triangles, bodies that were skipped. It is usually empty, and when it is not, ignoring it is how a hole ships.

Threads and robustness

Conversions are independent: four threads converting at once produce identical results. A malformed file returns CadConvertException with a reason rather than taking the process down — the native side catches any panic at the boundary, because unwinding into a host is undefined behaviour.

Runtimes

The package carries the native library for every runtime it was built for, under runtimes/{rid}/native: linux-x64, linux-arm64, osx-arm64, osx-x64, win-x64. If a P/Invoke fails at load time, the runtime you are on was not among them.

A .NET Core host finds those on its own. .NET Framework does not — it copies a runtime-specific file only when the project names a runtime identifier, and most do not — so the package brings a build/CadConvert.targets that puts the right one beside your executable, and warns at build time if it has none for the platform you are building for.

build/native/include/cadconvert.h is there for a caller that is not .NET at all; it describes the same library.

Source, benchmarks and the engineering record: https://github.com/omerbasavul/cadconvert