76 lines
3.6 KiB
Python
76 lines
3.6 KiB
Python
# IfcOpenShell - IFC toolkit and geometry engine
|
|
# Copyright (C) 2025 Thomas Krijnen <thomas@aecgeeks.com>
|
|
#
|
|
# This file is part of IfcOpenShell.
|
|
#
|
|
# IfcOpenShell is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU Lesser General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# IfcOpenShell is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU Lesser General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU Lesser General Public License
|
|
# along with IfcOpenShell. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
import ifcopenshell
|
|
import ifcopenshell.api.alignment
|
|
import ifcopenshell.util.element
|
|
import ifcopenshell.util.representation
|
|
from ifcopenshell import entity_instance
|
|
|
|
|
|
def create_segment_representations(
|
|
file: ifcopenshell.file,
|
|
alignment: entity_instance,
|
|
) -> None:
|
|
"""
|
|
Creates curve segment representations for the alignment for IFC CT 4.1.7.1.1.4. The alignment is expected to have representations
|
|
for "Axis/Curve2D" (horizontal only) or "FootPrint/Curve2D" and "Axis/Curve3D" (horizontal + vertical/cant). There is the additional
|
|
expectation that there is a 1-to-1 relationship between IfcAlignmentSegment and IfcCurveSegment.
|
|
That is, no Helmert curves in the alignment which have a 1-to-2 relationship
|
|
|
|
:param alignment: The alignment to create segment representations.
|
|
"""
|
|
expected_type = "IfcAlignment"
|
|
if not alignment.is_a(expected_type):
|
|
raise TypeError(f"Expected to see type '{expected_type}', instead received '{alignment.is_a()}'.")
|
|
|
|
axis_geom_subcontext = ifcopenshell.api.alignment.get_axis_subcontext(file)
|
|
representations = ifcopenshell.util.representation.get_representations_iter(alignment)
|
|
for representation in representations:
|
|
curve = None
|
|
nested_alignment = None
|
|
if (representation.RepresentationIdentifier == "Axis" and representation.RepresentationType == "Curve2D") or (
|
|
representation.RepresentationIdentifier == "FootPrint" and representation.RepresentationType == "Curve2D"
|
|
):
|
|
curve = ifcopenshell.api.alignment.get_basis_curve(alignment)
|
|
nested_alignment = next(
|
|
c for c in ifcopenshell.util.element.get_components(alignment) if c.is_a("IfcAlignmentHorizontal")
|
|
)
|
|
elif representation.RepresentationIdentifier == "Axis" and representation.RepresentationType == "Curve3D":
|
|
curve = ifcopenshell.api.alignment.get_curve(alignment)
|
|
nested_alignment = next(
|
|
c for c in ifcopenshell.util.element.get_components(alignment) if c.is_a("IfcAlignmentVertical")
|
|
)
|
|
|
|
curve_segments = curve.Segments
|
|
segments = nested_alignment.IsNestedBy[0].RelatedObjects
|
|
|
|
for curve_segment, alignment_segment in zip(curve_segments, segments):
|
|
axis_representation = file.create_entity(
|
|
type="IfcShapeRepresentation",
|
|
ContextOfItems=axis_geom_subcontext,
|
|
RepresentationIdentifier="Axis",
|
|
RepresentationType="Segment",
|
|
Items=(curve_segment,),
|
|
)
|
|
product = file.create_entity(
|
|
type="IfcProductDefinitionShape", Name=None, Description=None, Representations=(axis_representation,)
|
|
)
|
|
alignment_segment.ObjectPlacement = alignment.ObjectPlacement
|
|
alignment_segment.Representation = product
|