Cannot call BRep_Tool.Triangulation due to unbound types: N11opencascade6handleI18Poly_TriangulationEE

[flolu]

I'm using the following code from openCascadeHelper.js

const myFace = oc.TopoDS.Face_1(ExpFace.Current())
const aLocation = new oc.TopLoc_Location_1()
const myT = oc.BRep_Tool.Triangulation(myFace, aLocation, 0 /* == Poly_MeshPurpose_NONE */)

But the third line throws the following error:

UnboundTypeError: Cannot call BRep_Tool.Triangulation due to unbound types: N11opencascade6handleI18Poly_TriangulationEE

Which bindings am I missing? Is there a list of all available bindings? Note: the code works fine with the full build.

This is my current custom build file:

mainBuild:
  name: customBuild.examples.js
  bindings:
    - symbol: BRepTools
    - symbol: NCollection_BaseSequence
    - symbol: TDataStd_GenericEmpty
    - symbol: TDF_Attribute
    - symbol: TDF_LabelSequence
    - symbol: XSControl_Reader
    - symbol: STEPControl_Reader
    - symbol: IFSelect_ReturnStatus
    - symbol: RWGltf_CafWriter
    - symbol: TCollection_AsciiString
    - symbol: Handle_TDocStd_Document
    - symbol: TDocStd_Document
    - symbol: TColStd_IndexedDataMapOfStringString
    - symbol: Message_ProgressRange
    - symbol: XCAFDoc_DocumentTool
    - symbol: XCAFDoc_ShapeTool
    - symbol: BRepMesh_IncrementalMesh
    - symbol: TopoDS_Shape
    - symbol: Handle_XCAFDoc_ShapeTool
    - symbol: STEPCAFControl_Reader
    - symbol: NCollection_BaseMap
    - symbol: TDF_Label
    - symbol: BRepMesh_DiscretRoot
    - symbol: TCollection_ExtendedString
    - symbol: CDM_Document
    - symbol: Standard_Transient
    - symbol: TopExp_Explorer
    - symbol: TopAbs_ShapeEnum
    - symbol: TopoDS_Compound
    - symbol: TopoDS_Face
    - symbol: TopoDS_Builder
    - symbol: TopoDS_Edge
    - symbol: TopoDS_Wire
    - symbol: TopoDS
    - symbol: TopoDS_Iterator
    - symbol: TopLoc_Location
    - symbol: Poly_Connect
    - symbol: BRep_Tool
    - symbol: TColgp_Array1OfDir
    - symbol: StdPrs_ToolTriangulatedShape
    - symbol: Poly_Triangulation
    - symbol: RWMesh_TriangulationSource
  emccFlags:
    - -flto
    - -fexceptions
    - -sDISABLE_EXCEPTION_CATCHING=1
    - -O3
    - -sEXPORT_ES6=1
    - -sUSE_ES6_IMPORT_META=0
    - -sEXPORTED_RUNTIME_METHODS=['FS']
    - -sINITIAL_MEMORY=15MB
    - -sMAXIMUM_MEMORY=4GB
    - -sALLOW_MEMORY_GROWTH=1
    - -sLLD_REPORT_UNDEFINED
    - --no-entry
    - -sENVIRONMENT='web'

[donalffons]

N11opencascade6handleI18Poly_TriangulationEE is the mangled type name. You can use a Demangler to get the original type name by prepending _Z, i.e. _ZN11opencascade6handleI18Poly_TriangulationEE. This gives you opencascade::handle<Poly_Triangulation>. That type has already been explicitly defined here in OCCT with a macro that defines it as Handle_Poly_Triangulation. To make template types usable in JS, the template argument has to be resolved by using a typedef.

Long story short: I think you need to add - symbol: Handle_Poly_Triangulation.

If you ever need to use template types that haven't been defined in OCCT in a similar way, check the full build - it contains a typedef for Handle_IMeshTools_Context.

[flolu]

Thank you so much for your quick response! This worked.

---

But what about 18NCollection_Array1I13Poly_TriangleE?

The demangler outputs: NCollection_Array1<Poly_Triangle>, but the symbol NCollection_Array1_Poly_Triangle does not exist. NCollection_Array_Poly_Triangle does not exist, either.

I've also tried BRepMesh_Triangulator as defined here in OCCT. But I still get the error: UnboundTypeError: Cannot call Poly_Triangulation.Triangles due to unbound types: 18NCollection_Array1I13Poly_TriangleE

[donalffons]

But what about 18NCollection_Array1I13Poly_TriangleE?

That is typedef'd here as Poly_Array1OfTriangle.

[donalffons]

The type can also be seen in typescript definitions (opencascade.d.ts via npm) and the reference docs.

[flolu]

Thank you so much!