BREP Kernel Reference

This page catalogs the core classes and helpers that make up the BREP kernel (everything under src/BREP). Use it alongside docs/solid-methods.md for Solid details and docs/brep-api.md for the export map.

Core types

  • Solid / Face / Edge / Vertex – Geometry + selection primitives (Solid API in docs/solid-methods.md).
  • AssemblyComponent – Groups one or more solids for the assembly constraint solver. Options: { name='Component', fixed=false }.

Primitives (src/BREP/primitives.js)

All extend Solid and immediately generate geometry.

  • Cube({ x=1, y=1, z=1, name })
  • Pyramid({ bL=1, s=4, h=1, name }) (s is side count ≥ 3)
  • Sphere({ r=1, resolution=24, name })
  • Cylinder({ radius=1, height=1, resolution=32, name })
  • Cone({ r1=0.5, r2=1, h=1, resolution=32, name })
  • Torus({ mR=2, tR=0.5, resolution=48, arcDegrees=360, name })

Feature solids

- ExtrudeSolid – { face, distance=1 | dir:Vector3, distanceBack=0, name='Extrude' }.

  • Sweep – { face, sweepPathEdges=[], distance=1, distanceBack=0, mode='translate', name='Sweep', omitBaseCap=false }.
  • Revolve – { face, axis, angle=360, resolution=64, name='Revolve' }.
  • TubeSolid (Tube) – { points=[], radius=1, innerRadius=0, resolution=32, closed=false, name='Tube' }.

- ChamferSolid – { edgeToChamfer, distance=1, sampleCount=50, snapSeamToEdge=true, sideStripSubdiv=8, seamInsetScale=1e-3, direction='INSET'|'OUTSET', inflate=0, flipSide=false, debug=false, debugStride=12 }.

  • OffsetShellSolid.generate(sourceSolid, distance, { newSolidName, featureId='OffsetShell' }) – Static helper to build offset shells.

Fillet utilities (src/BREP/fillets/fillet.js)

- filletSolid({ edgeToFillet, radius, sideMode='INSET'|'OUTSET', inflate=0.1, resolution=32, showTangentOverlays=false, debug=false, name='fillet' }) – Builds wedge/tube helpers and returns { finalSolid, tube, wedge }; overlays add tangency polylines to the tube for debugging/PMI tagging.

  • computeFilletCenterline(edgeObj, radius, sideMode) – Returns centerline/tangents/edge polylines plus a closedLoop flag.
  • attachFilletCenterlineAuxEdge(solid, edgeObj, radius, sideMode='INSET', name='FILLET_CENTERLINE', options) – Adds centerline as an aux edge; options mirrors Solid.addAuxEdge.

Boolean helper

- applyBooleanOperation(partHistory, baseSolid, booleanParam, featureID) – Runs UNION|INTERSECT|SUBTRACT between baseSolid and booleanParam.targets (objects or names). Returns { added, removed }. Subtract semantics invert: each target subtracts the new base.

Conversion and repair

  • MeshToBrep – new MeshToBrep(geometryOrMesh, faceDeflectionAngle=30, weldTolerance=1e-5) groups triangles into faces based on normal deflection and welds shared vertices.
  • MeshRepairer – Per-geometry repair pipeline:

    • - weldVertices(geometry, epsilon=1e-4) - fixTJunctions(geometry, lineEps=5e-4, gridCell=0.01) - removeOverlappingTriangles(geometry, posEps=1e-6) - fillHoles(geometry) - fixTriangleNormals(geometry) - repairAll(geometry, { weldEps=5e-4, lineEps=5e-4, gridCell=0.01 })

  • Point cloud wrapper – buildTightPointCloudWrap(rawPoints, { padding=0.02*diag, alphaRadius=0.6*medianKNN }) builds a solid via marching cubes over a density field.

Misc helpers

  • MeshToBrep, MeshRepairer, applyBooleanOperation, PointCloudWrap live in src/BREP and are re-exported via BREP.js (docs/brep-api.md).
  • SolidMethod docs – docs/solid-methods.md covers all core operations (authoring, cleanup, booleans, export).

Example: boolean with primitives

js
import { BREP } from '../src/BREP/BREP.js';

const box = new BREP.Cube({ x: 20, y: 10, z: 10, name: 'Box' });
const hole = new BREP.Cylinder({ radius: 3, height: 10, name: 'Hole' });
hole.position.set(10, 5, 0);
hole.bakeTransform(hole.matrixWorld);

const result = box.subtract(hole);
result.name = 'BoxWithHole';
result.visualize();