Adds alignment as offset curve

2026-08-11 10:06:47 +00:00 · 2025-07-17 10:47:13 -07:00
parent 728f9e2c04
commit a392a1fbfb
9 changed files with 407 additions and 12 deletions
@@ -0,0 +1,138 @@
+# 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 pytest
+import math
+import ifcopenshell.api.alignment
+import ifcopenshell.api.unit
+
+
+def test_create_as_offset_curve():
+    file = ifcopenshell.file(schema="IFC4X3_ADD2")
+    project = file.createIfcProject(GlobalId=ifcopenshell.guid.new(), Name="OCBD Test Alignment")
+    length = ifcopenshell.api.unit.add_si_unit(file, unit_type="LENGTHUNIT")
+    ifcopenshell.api.unit.assign_unit(file, units=[length])
+
+    # create main alignment
+    alignment = ifcopenshell.api.alignment.create(file, "A1", include_vertical=True)
+    layout = ifcopenshell.api.alignment.get_horizontal_layout(alignment)
+
+    segment1 = file.createIfcAlignmentHorizontalSegment(
+        StartPoint=file.createIfcCartesianPoint(Coordinates=((0.0, 0.0))),
+        StartDirection=0.0,
+        StartRadiusOfCurvature=0.0,
+        EndRadiusOfCurvature=0.0,
+        SegmentLength=500,
+        PredefinedType="LINE",
+    )
+
+    end = ifcopenshell.api.alignment.create_layout_segment(file, layout, segment1)
+
+    unit_scale = ifcopenshell.util.unit.calculate_unit_scale(file)
+
+    x = float(end[0, 3]) / unit_scale
+    y = float(end[1, 3]) / unit_scale
+    dx = float(end[0, 0])
+    dy = float(end[1, 0])
+    dir = math.atan2(dy, dx)
+    segment2 = file.createIfcAlignmentHorizontalSegment(
+        StartPoint=file.createIfcCartesianPoint((x, y)),
+        StartDirection=dir,
+        StartRadiusOfCurvature=0.0,
+        EndRadiusOfCurvature=1000.0,
+        SegmentLength=100,
+        PredefinedType="CLOTHOID",
+    )
+    end = ifcopenshell.api.alignment.create_layout_segment(file, layout, segment2)
+
+    x = float(end[0, 3]) / unit_scale
+    y = float(end[1, 3]) / unit_scale
+    dx = float(end[0, 0])
+    dy = float(end[1, 0])
+    dir = math.atan2(dy, dx)
+    segment3 = file.createIfcAlignmentHorizontalSegment(
+        StartPoint=file.createIfcCartesianPoint((x, y)),
+        StartDirection=dir,
+        StartRadiusOfCurvature=1000.0,
+        EndRadiusOfCurvature=1000.0,
+        SegmentLength=1500.0,
+        PredefinedType="CIRCULARARC",
+    )
+    end = ifcopenshell.api.alignment.create_layout_segment(file, layout, segment3)
+
+    x = float(end[0, 3]) / unit_scale
+    y = float(end[1, 3]) / unit_scale
+    dx = float(end[0, 0])
+    dy = float(end[1, 0])
+    dir = math.atan2(dy, dx)
+    segment4 = file.createIfcAlignmentHorizontalSegment(
+        StartPoint=file.createIfcCartesianPoint((x, y)),
+        StartDirection=dir,
+        StartRadiusOfCurvature=1000.0,
+        EndRadiusOfCurvature=0.0,
+        SegmentLength=100,
+        PredefinedType="CLOTHOID",
+    )
+    end = ifcopenshell.api.alignment.create_layout_segment(file, layout, segment4)
+
+    x = float(end[0, 3]) / unit_scale
+    y = float(end[1, 3]) / unit_scale
+    dx = float(end[0, 0])
+    dy = float(end[1, 0])
+    dir = math.atan2(dy, dx)
+    segment5 = file.createIfcAlignmentHorizontalSegment(
+        StartPoint=file.createIfcCartesianPoint((x, y)),
+        StartDirection=dir,
+        StartRadiusOfCurvature=0.0,
+        EndRadiusOfCurvature=0.0,
+        SegmentLength=800.0,
+        PredefinedType="LINE",
+    )
+    end = ifcopenshell.api.alignment.create_layout_segment(file, layout, segment5)
+
+    # create vertical for main alignment
+    vlayout = ifcopenshell.api.alignment.get_vertical_layout(alignment)
+
+    segment1 = file.createIfcAlignmentVerticalSegment(
+        StartDistAlong=0.0,
+        HorizontalLength=3000.0,
+        StartHeight=100.0,
+        StartGradient=1.75 / 100.0,
+        EndGradient=1.75 / 100.0,
+        PredefinedType="CONSTANTGRADIENT",
+    )
+
+    end = ifcopenshell.api.alignment.create_layout_segment(file, vlayout, segment1)
+
+    # create the offset alignment
+    basis_curve = ifcopenshell.api.alignment.get_curve(alignment)  # want the IfcGradientCurve
+
+    offsets = [
+        file.createIfcPointByDistanceExpression(
+            DistanceAlong=file.createIfcLengthMeasure(0.0), OffsetLateral=100.0, BasisCurve=basis_curve
+        ),
+    ]
+
+    offset_alignment = ifcopenshell.api.alignment.create_as_offset_curve(file, "A2", offsets)
+    assert offset_alignment.is_a("IfcAlignment")
+    curve = ifcopenshell.api.alignment.get_curve(offset_alignment)
+    assert curve.is_a("IfcOffsetCurveByDistances")
+    assert curve.BasisCurve == basis_curve
+
+
+test_create_as_offset_curve()