OCCTSwiftIO Cookbook

Task-oriented, example-rich guides for the OCCTSwiftIO + MeshIO API — one page per task, each a short bit of prose followed by runnable Swift snippets using the real shipped API.

Conventions

• Every example is runnable Swift in a fenced swift block, using the real current API. Fallible loaders / exporters are throws; the CAD loaders are async throws. Mesh I/O is synchronous.
• Two imports, two charters. import MeshIO for the pure-Swift mesh path (no OCCT); import OCCTSwift
  • import OCCTSwiftIO for CAD B-Rep, JWW, manifests, and ML export.
• Format by extension. Both CADFileFormat(fileExtension:) and MeshFormat(fileExtension:) map a file extension to a format case; MeshIO.load / MeshIO.write do this for you.

Pages

• Importing a CAD file — ShapeLoader.load / loadRobust, CADFileFormat, colors + AP242 metadata.
• Exporting shapes — ExportManager.export to STEP / BREP / OBJ / PLY / glTF / GLB.
• Reading & writing meshes — MeshIO.load / write, the Mesh value type, the per-format readers.
• The ScriptManifest format — ShapeLoader.loadFromManifest, ScriptManifest / BodyDescriptor.
• Progress reporting — ImportProgressClosure, fraction + step callbacks, cancellation.
• ML graph export — TopologyGraph.exportForML() / exportJSON(), the COO adjacency layout.

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Table of contents

• Importing a CAD file
• Exporting shapes
• Reading & writing meshes
• The ScriptManifest format
• Progress reporting
• ML graph export