Topology graph

Low-level B-rep graph operations that work directly on an absolute BREP file path rather than a scene body. Use these when you need raw topology analysis, graph compaction, ML export, or local adjacency queries — call the scene-aware wrappers (validate_geometry, recognize_features) when working with bodies already loaded in the scene.

Tools

• graph_validate · graph_compact · graph_dedup · graph_ml · graph_select · feature_recognize

graph_validate

Raw-path topology validation. Pass an absolute BREP path; use validate_geometry for the scene-aware version.

Server: Swift + Node

Parameters

Returns — Topology validity report for the shape at brep_path. Reports errors/warnings on individual sub-shapes.

Example

// tool call arguments
{ "brep_path": "/Users/me/Library/Mobile Documents/com~apple~CloudDocs/OCCTSwiftScripts/output/part.brep" }

// example result
{ "valid": true, "errors": [], "warnings": [] }

Notes — For bodies already in the scene, prefer validate_geometry (takes a bodyId).

graph_compact

Compact a BREP’s topology graph (drops unreferenced nodes); writes the rebuilt shape to output_path.

Server: Swift + Node

Parameters

Returns — Confirmation that the compacted shape was written to output_path, plus node counts before and after.

Example

// tool call arguments
{
  "brep_path": "/Users/me/.occtswift-scripts/output/part.brep",
  "output_path": "/Users/me/.occtswift-scripts/output/part_compact.brep"
}

// example result
{ "output_path": "/Users/me/.occtswift-scripts/output/part_compact.brep", "nodesRemoved": 4 }

graph_dedup

Deduplicate shared surface/curve geometry in a BREP’s topology graph; writes the rebuilt shape to output_path.

Server: Swift + Node

Parameters

Returns — Confirmation that the deduplicated shape was written to output_path.

Example

// tool call arguments
{
  "brep_path": "/Users/me/.occtswift-scripts/output/assembly.brep",
  "output_path": "/Users/me/.occtswift-scripts/output/assembly_dedup.brep"
}

// example result
{ "output_path": "/Users/me/.occtswift-scripts/output/assembly_dedup.brep", "geometriesDeduped": 12 }

graph_ml

Export a BREP’s topology graph as ML-friendly JSON. Wraps ScriptHarness BREPGraphJSONExporter, augmented with a faceAdjacency block — the convexity-attributed gAAG edge attribute with face indices in shape.faces() order.

Server: Swift + Node

Parameters

Returns — ML-friendly JSON containing nodes (faces, edges, vertices with UV/edge samples), edges (topology adjacency), and a faceAdjacency block with { face1, face2, convexity, sharedEdgeCount } entries.

Each nodes.edges[] entry also carries convexity (convex, concave, smooth or unknown) and dihedralAngle (the interior angle in radians: pi/2 on a cube edge, 3 pi/2 on an inside corner, absent when unknown). unknown is an edge that is not between exactly two faces, such as the boundary of an open shell. meta.schemaVersion is 1.1.0. The Swift server passes the source shape to the exporter (#231), so it always emits these keys. The Node server relays occtkit graph-ml verbatim and gains them when the installed occtkit includes OCCTSwiftScripts#139; an older occtkit omits them.

Example

// tool call arguments
{
  "brep_path": "/Users/me/.occtswift-scripts/output/part.brep",
  "description": "bracket v2"
}

// example result
{
  "description": "bracket v2",
  "nodes": [ { "kind": "face", "index": 0 }, "..." ],
  "faceAdjacency": [
    { "face1": 0, "face2": 1, "convexity": "convex", "sharedEdgeCount": 1 }
  ]
}

Notes — Face indices in faceAdjacency follow shape.faces() order, consistent with query_topology’s face[N] scheme. The kernel’s attributed adjacency graph numbers face occurrences (orientedFaces()), which differ from faces() when two solids in a compound share a face, so the indices are converted and the shared face’s occurrences are merged (#201): shared-edge counts add, duplicate pairs collapse and self-edges are dropped.

graph_select

Local B-rep graph adjacency/selection query — returns a focused neighbourhood rather than a full graph dump.

Server: Swift only

Parameters

Returns — Depends on query:

• face-neighbors — adjacent face indices, convexity per shared edge, shared-edge count.
• edge-faces — face indices on both sides of the given edge.
• vertex-edges — edge indices incident to the given vertex.
• face-adjacency — full attributed face-adjacency graph (gAAG) for the shape.
• edges-class — indices of all edges matching the given class.

Example

// tool call arguments — face neighbours with convexity
{
  "brep_path": "/Users/me/.occtswift-scripts/output/part.brep",
  "query": "face-neighbors",
  "face": 2
}

// example result
{
  "face": 2,
  "neighbors": [
    { "face": 0, "convexity": "convex", "sharedEdgeCount": 1 },
    { "face": 3, "convexity": "concave", "sharedEdgeCount": 1 }
  ]
}

Notes — Face indices (face-neighbors, face-adjacency) are in shape.faces() order even on compounds with a shared face (#201; before that fix they were orientedFaces() occurrence indices). For the same neighbour data on a scene body, query_topology takes includeNeighbors. The correct secondary parameter to supply depends on query: face for face-neighbors, edge for edge-faces, vertex for vertex-edges, class for edges-class; none needed for face-adjacency. This tool is Swift only — Node clients must use graph_ml for adjacency data.

feature_recognize

Detect pockets and holes via AAG heuristics. Pass an absolute BREP path; recognize_features is the scene-aware variant.

Server: Swift + Node

Parameters

Returns — List of detected features (pockets, holes) with their face-index sets and geometry parameters.

Example

// tool call arguments
{ "brep_path": "/Users/me/.occtswift-scripts/output/part.brep" }

// example result
{
  "features": [
    { "kind": "hole", "faces": [4, 5], "diameter": 6.0 },
    { "kind": "pocket", "faces": [6, 7, 8], "depth": 5.0 }
  ]
}

Notes — For bodies already in the scene, prefer recognize_features (takes a bodyId). Face indices follow shape.faces() order.