Add support for IfcSectionedSurface

src/ifcgeom/mapping/IfcSectionedSurface.cpp

@@ -0,0 +1,93 @@
+/********************************************************************************
+ *                                                                              *
+ * This file is part of IfcOpenShell.                                           *
+ *                                                                              *
+ * IfcOpenShell is free software: you can redistribute it and/or modify         *
+ * it under the terms of the Lesser GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3.0 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                 *
+ * Lesser GNU General Public License for more details.                          *
+ *                                                                              *
+ * You should have received a copy of the Lesser GNU General Public License     *
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.         *
+ *                                                                              *
+ ********************************************************************************/
+
+#include "mapping.h"
+#define mapping POSTFIX_SCHEMA(mapping)
+using namespace ifcopenshell::geometry;
+
+#include "../../ifcgeom/profile_helper.h"
+#include "../../ifcgeom/infra_sweep_helper.h"
+
+#ifdef SCHEMA_HAS_IfcSectionedSurface
+
+
+taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSectionedSurface* inst) {
+	std::vector<cross_section> cross_sections;
+
+	auto dir = map(inst->Directrix());
+	auto pwf = taxonomy::dcast<taxonomy::piecewise_function>(dir);
+	if (!pwf) {
+		// Only implement on alignment curves
+        Logger::Warning("IfcSectionedSurface is only implemented for piecewise function Directrix curves", inst);
+        return nullptr;
+	}
+
+	{	
+	auto css = inst->CrossSections();
+	auto csps = inst->CrossSectionPositions();
+	std::vector<taxonomy::geom_item::ptr> faces;
+
+	// The PointByDistanceExpressesions are factored out into (a) a cartesian offset relative to the
+	// reference frame along a certain curve location (b) the longitude.
+
+	// The longitudes determine the range of the sweep and the offsets are interpolated in between
+	// sweep segments. 
+	std::vector<Eigen::Vector3d> profile_offsets;
+	std::vector<double> longitudes;
+
+	for (auto& cs : *css) {
+		faces.push_back(std::move(taxonomy::cast<taxonomy::geom_item>(map(cs))));
+	}
+#ifdef SCHEMA_HAS_IfcPointByDistanceExpression
+	for (auto& csp : *csps) {
+		auto pbde = csp->Location()->as<IfcSchema::IfcPointByDistanceExpression>(true);
+
+		longitudes.push_back(*pbde->DistanceAlong()->as<IfcSchema::IfcLengthMeasure>(true) * length_unit_);
+
+		// Corresponds to the profile X, Y directions (hopefully).
+		Eigen::Vector3d po(
+			pbde->OffsetLateral().get_value_or(0.),
+			// @todo I don't understand whether vertical is an offset relative to the tangent plane or to the global XY plane
+			pbde->OffsetVertical().get_value_or(0.),
+			0.
+		);
+
+		profile_offsets.push_back(po);
+	}
+#else
+	return nullptr;
+#endif
+	if (faces.size() != profile_offsets.size()) {
+		Logger::Warning("Expected CrossSections and CrossSectionPositions to be equal length, but got " + std::to_string(faces.size()) + " and " + std::to_string(profile_offsets.size()) + " respectively", inst);
+		return nullptr;
+	}
+	if (faces.size() < 2) {
+		Logger::Warning("Expected at least two cross sections, but got " + std::to_string(faces.size()), inst);
+		return nullptr;
+	}
+
+	for (size_t i = 0; i < faces.size(); ++i) {
+		cross_sections.push_back({ longitudes[i], faces[i], profile_offsets[i] });
+	}
+	}
+
+	return make_loft(settings_, inst, pwf, cross_sections);
+}
+
+#endif