OCCTSwift API Reference

A detailed, per-type function reference for the OCCTSwift Swift API — modelled on OCCT’s own Doxygen class reference (dev.opencascade.org, indexed on context7 as /open-cascade-sas/occt). One page per public Swift type, every public method documented: signature, behaviour, parameters, return, the OCCT class/method it wraps, a runnable example, and gotchas.

This complements the other docs — it’s the exhaustive surface, vs:

• API_REFERENCE.md — the compact Swift→OCCT mapping table.
• guides/cookbook/ — task-oriented example pages.

Generation. These pages are produced by subagents (see /document-api), one per source file, each reading the Swift source + the OCCTBridge mapping + the upstream OCCT docs. Built over time; see Status for coverage.

Page layout

One file docs/reference/<Type>.md per public Swift type (matching Sources/OCCTSwift/<Type>.swift). Large types are split by their // MARK: sections into <Type>-<Area>.md (see Status).

Each page:

---
title: <Type>
parent: API Reference
---

# <Type>

<1–3 sentences: what the type represents, its OCCT analog(s), and how you obtain one.>

## Topics

- [<Group A>](#group-a) · [<Group B>](#group-b) · …

---

## <Group>        ← one ## per source `// MARK:` section, in source order

### `Type.method(label:)`     ← `###` per public member, in source order

<one-line summary — what it does.>

​```swift
public func method(label: Type) -> ReturnType
​```

<optional 1–2 sentences of detail / when to use.>

- **Parameters:** `label` — meaning. *(omit if none)*
- **Returns:** what comes back; **state nil/throws conditions** for optionals/throwing calls.
- **OCCT:** `Upstream_Class::Method` — the wrapped C++ API. *(omit only if pure-Swift)*
- **Example:**
  ​```swift
  let r = Type.method(label: …)
  ​```
- **Note:** gotchas / edge cases. *(omit if none)*

Entry rules (the template contract)

1. Signature is verbatim from the source — copy the full public declaration, including defaults.
2. Every public func / var / static func / init of the type gets a ### entry, in source order, grouped under its // MARK: section.
3. OCCT mapping is required wherever the method calls a bridge function — name the upstream class (BRepBuilderAPI_MakeWire, Geom_BSplineCurve, …). Find it from the bridge .mm implementation or the cross-reference index in OCCTBridge.h. Omit only for pure-Swift helpers.
4. Examples must be signature-faithful and runnable. Reuse a snippet from a cookbook page or a test where one exists (these are compile-checked); otherwise write a minimal, type-correct one. Fallible APIs unwrap with guard/if let, never force-unwrap.
5. No invention. Behaviour comes from the source doc comment, the bridge, and the OCCT docs — not guessed. If a method’s purpose is unclear, say so briefly rather than fabricate.
6. Concise. Reference, not prose — one tight summary line, parameters/returns as bullets.

Rollout

• Unit of work: one source file = one subagent job. Run a batch per session; /document-api <Type> for a single page.
• Order: core types first (Shape, Wire, Surface, Curve3D, Curve2D, Edge, Face, Mesh), then I/O & documents (Exporter, Document), then the long tail (drawing, annotation, measurement, etc.).
• Giants (Document ~1865, Shape ~993, BRepGraph, Surface, Curve2D, Curve3D): split by // MARK: section into <Type>-<Area>.md, one subagent per chunk, linked from the type’s index page.

Status

Coverage tracker — update as pages land. (Counts = public decls in the source file.)

Table of contents

• 2D Geometry Primitives
• Annotation & GD&T
• Bill of Materials & Selection
• Color & Material
• Concurrency & Progress
• Construction & Sketching
• Curve Adaptors & Wire Ordering
• Curve2D
• Curve2D — Analysis
• Curve2D — Analytic Types
• Curve2D — Constraint Solvers
• Curve3D
• Curve3D — Analysis
• Curve3D — Analytic Types
• Curve3D — Construction
• Date & Period
• Display & Presentation
• Document
• Document — BSpline/Bezier Methods & Extrema
• Document — Builders, Fillet/Chamfer & glTF
• Document — Coordinate Systems, Transforms & Completions
• Document — Geometry Constructors & Pipe Shells
• Document — Math Solvers & Local Properties
• Document — Math, Bounds, OSD & Conversions
• Document — Mesh I/O, Projection & Shape Fixing
• Document — OCAF Attributes, Naming & Elementary Geometry
• Document — Persistence, I/O & XDE Tools
• Document — Shape Analysis, OSD & Geometry Builders
• Document — XCAF & API Completions
• Document — XCAF Notes, Views & Materials
• Drawing & Sheets
• Drawing Automation & Helpers
• DrawingAnnotation
• Edge
• Exporter
• Face
• Feature Recognition & Medial Axis
• FeatureReconstructor
• Geometry Solvers & Builders
• Measurement
• Mesh
• Shape
• Shape — Advanced Sweeps & API Completions
• Shape — Builders & Boolean Internals I
• Shape — Builders & Boolean Internals II
• Shape — Features, Sweeps & Surface Building
• Shape — Geometry Recognition & Polygon/Triangulation Data
• Shape — HLR, Intervals, Mesh Props & Geom Primitives
• Shape — Healing, Recognition & Feature Ops
• Shape — Measurement, Sub-Shapes & Local Operations
• Sheet Metal
• Surface
• Surface — Advanced Construction
• Surface — Analysis
• Surface — Analytic Types
• Surface — BSpline & Bezier
• ThreadFeatures
• TopologyGraph
• TopologyGraph — Attributes, Snapshots & References
• TopologyGraph — Builders & Editor Mutation
• TopologyGraph — Editor Geometry, Sampling & Durable Identity
• TopologyGraph — Topology Detail, History & Mesh
• Vector & Raster Export
• Wire