Source code for pyvcad_metamaterials.occ

"""Lazy raw OCP shape adapters using in-memory ASCII BREP streams."""

# STD
from io import BytesIO

# OpenVCAD
import pyvcad as pv


def _ocp():
    try:
        from OCP.BRepTools import BRepTools
        from OCP.TopoDS import TopoDS_Shape
    except ImportError as error:
        raise ImportError(
            "OCP support is optional. Install OpenVCAD[cad] or "
            "pyvcad-metamaterials[cad] to use mm.occ."
        ) from error
    return BRepTools, TopoDS_Shape


def _model(shape):
    brep_tools, shape_type = _ocp()
    if not isinstance(shape, shape_type):
        raise TypeError("expected an OCP TopoDS_Shape")
    with BytesIO() as stream:
        brep_tools.Write_s(shape, stream)
        return pv.CADModel.from_brep_bytes(stream.getvalue())




def body(shape):
    """Convert a raw OCP shape into a topology-preserving CADModel."""
    return _model(shape)





def face(shape):
    """Convert one raw OCP face into a CADFace."""
    model = _model(shape)
    if len(model.faces) != 1:
        raise ValueError("OCP face adapter requires a shape containing exactly one face")
    return model.faces[0]





def faces(shapes):
    """Convert raw OCP faces into independent CADFace handles."""
    return [face(shape) for shape in shapes]