Exporting STEP to THREEJS --> Assembly structure lost in JSON file

[freddida]

Hello pythonocc-community,

Issue I want to export a step file as a json string to use it in threejs using the following code:

step_reader = STEPControl_Reader()
status = step_reader.ReadFile(inputFile)

if status == IFSelect_RetDone:  # check status
    failsonly = False
    step_reader.PrintCheckLoad(failsonly, IFSelect_ItemsByEntity)
    step_reader.PrintCheckTransfer(failsonly, IFSelect_ItemsByEntity)

    step_reader.TransferRoot(1)
    _nbs = step_reader.NbShapes()
    _shape = step_reader.Shape(1)
    _tess = ShapeTesselator(_shape)
    _tess.Compute(compute_edges=False, mesh_quality=1, parallel=True)

    with open(outputFile, "w") as text_file:
        json = _tess.ExportShapeToThreejsJSONString(inputFile)
        json = json.replace("\\", "/")
        text_file.write(json)
else:
    raise Exception("Error: can't read file - Method: _load_STEP_file"))`

The json file is working fine but the file structure of the step is lost. File: turbine_stp.zip

Expected behavior The json string should contain the threejs structure (e.g. different parts, ect.)

Question Is there a possibility to achieve this?

• Version: [latest]

[gkv311]

Just curious, why not converting STEP document into glTF file using STEPCAFControl_Reader and RWGltf_CafWriter? It would try to keep assembly structure, and Three.js has glTF reader.

[freddida]

Hey,

Thank you! I was not aware of these functions! Would you be so kind to provide the code you used for this output?