PLM Automated Conversion

Background conversion engine for CAD files inside Odoo PLM. Converts source documents to derivative formats (preview images, 3D web models) automatically via a job queue, and on-demand when opening the 3D viewer.

Supported Conversions

STEP Name Preservation

Standard CadQuery STEP import uses the definition label (shared part name) for all instances, causing duplicate-name errors in assemblies where the same part appears more than once. This module includes a custom importer that reads the instance label (comp_label) from the XCAF document for each placement, falling back to the definition name only when the instance has none.

# Simplified logic inside _import_step_preserve_names()
inst_name = _get_name(comp_label) or _get_name(ref_label) or f"part_{i}"
# Guarantee uniqueness within this parent level
if inst_name in name_counter:
    name_counter[inst_name] += 1
    inst_name = f"{inst_name}_{name_counter[inst_name]}"

This ensures the component tree in glTF/3MF output matches the original CAD assembly structure.

3MF Export

The built-in CadQuery 3MF exporter does not preserve assembly hierarchy or component names. This module provides a custom exporter (_export_assembly_to_3mf) that:

• Traverses the full assembly tree recursively
• Tessellates each leaf shape with its accumulated world transform applied
• Writes a valid 3MF ZIP with one named <object> per component
• Registers the 3MF namespace as the default XML namespace so querySelectorAll('object') in Three.js finds elements correctly (avoids ns0: prefix issue from Python's ElementTree)

Preview Image Copying

When a conversion job completes, the preview image (ir.attachment.preview) from the source document is copied to the converted document. This allows the converted 3MF or glTF to display the same thumbnail as the original STEP file.

Job Queue (plm.convert.stack)

Conversions are queued as plm.convert.stack records and processed by a scheduled action. This prevents long-running CAD conversions from blocking the Odoo web request.

On-Demand Conversion (3D Web Integration)

When a user clicks 3D Web on a STEP attachment, the plm_web_3d module calls _get_or_create_3mf_from_step():

1. Search for an existing ir.attachment where source_convert_document = this_step and name ends in .3mf.
2. If found — open it immediately (no re-conversion).
3. If not found — call convert_from_step_to('.3mf'), create a new ir.attachment, copy the preview, and open the result.

Python Dependencies

pip install ezdxf
pip install matplotlib
pip install cadquery        # includes OpenCASCADE (OCP)
pip install numpy-stl
pip install to-3mf

Conversion Format Records

plm.convert.format records in data/data.xml define which source extensions are automatically queued for conversion. Pre-configured records include: