forgekernel 0.9.1

Exact-arithmetic B-rep CAD kernel

forge

An exact-arithmetic boundary-representation (B-rep) CAD kernel. Geometric and topological decisions use exact rational arithmetic (ℚ, ℚ[π], ℚ[√d]) or certified intervals; no result depends on a floating-point tolerance.

It ships as two PyPI packages:

• forgekernel — the kernel, pure Python.
• forgekernel_rs — a native (Rust) build of the performance-critical routines, installed automatically when a wheel is available and returning the same results.

Capabilities

• Planar solids: rational linear algebra, plane-based B-rep, booleans, divergence-theorem mass properties.
• Quadrics (cylinder, cone, sphere, torus) with closed-form intersections.
• NURBS curves and surfaces; surface–surface intersection with complete branch detection and certified points.
• Procedural offsets and shells; edge blends (fillets); lofts.
• Exact volume, centroid, and inertia via the divergence theorem.
• STEP (AP203/AP214) import and export.

Design

A Python reference implementation defines the exact semantics. A Rust build provides the same operations for production use; each ported routine is cross-checked against the reference. Design notes and decisions are recorded in the gitcad repository (ADR-0018).

Layout

• src/forgekernel/ — the Python kernel.
• rust/forge-core/ — the native build (forgekernel_rs).

Install

pip install forgekernel          # pure Python
pip install forgekernel[rust]    # add the native build

License: Apache-2.0. Source: https://github.com/gitcad-xyz/forge