Implements IfcSegmentedReferenceCurve and first cut at cant geometry

2026-08-12 18:43:26 +00:00 · 2023-11-08 19:42:41 -08:00
parent 809668c015
commit 7ed85358f9
3 changed files with 247 additions and 60 deletions
@@ -0,0 +1,84 @@
+/********************************************************************************
+ *                                                                              *
+ * 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;
+
+#ifdef SCHEMA_HAS_IfcSegmentedReferenceCurve
+
+taxonomy::ptr mapping::map_impl(const IfcSchema::IfcSegmentedReferenceCurve* inst) {
+   if (!inst->BaseCurve()->as<IfcSchema::IfcGradientCurve>())
+       Logger::Warning("Expected IfcSegmentedReferenceCurve.BaseCurve to be IfcGradient", inst); // CT 4.1.7.1.1.3
+		  
+	auto gradient = taxonomy::cast<taxonomy::piecewise_function>(map(inst->BaseCurve()));
+	auto cant = taxonomy::make<taxonomy::piecewise_function>();
+
+	auto segments = inst->Segments();
+
+	for (auto& segment : *segments) {
+		if (segment->as<IfcSchema::IfcCurveSegment>()) {
+			// @todo check that we don't get a mixture of implicit and explicit definitions
+			auto crv = map(segment->as<IfcSchema::IfcCurveSegment>());
+			if (crv->kind() == taxonomy::PIECEWISE_FUNCTION) {
+				auto seg = taxonomy::cast<taxonomy::piecewise_function>(crv);
+				cant->spans.insert(cant->spans.end(), seg->spans.begin(), seg->spans.end());
+			} else {
+				Logger::Error("Unsupported");
+				return nullptr;
+			}
+		} else {
+			Logger::Error("Unsupported");
+			return nullptr;
+		}
+	}
+
+	auto composition = [gradient, cant](double u)->Eigen::Matrix4d {
+		auto xyz = gradient->evaluate(u);
+		auto c = cant->evaluate(u);
+      c.col(3)(0) = 0;
+      std::swap(c.col(3)(1),c.col(3)(2));
+      Eigen::Matrix4d m;
+      m = xyz * c;
+      return m;
+	};
+
+	std::array<taxonomy::piecewise_function::ptr, 2> both = { gradient , cant };
+	// @todo: rb - this constrains the range of u to the minimum of gradient and cant
+	// we discussed using the maximum for the range of us and then using std::numeric_limits<double>::NAN
+	// for values of u that gradient or cant cannot be computed.
+	// Review and decide what to do.
+	double min_length = std::numeric_limits<double>::infinity();
+	for (auto i = 0; i < 2; ++i) {
+		double l = 0;
+		for (auto& s : both[i]->spans) {
+			l += s.first;
+		}
+		if (l < min_length) {
+			min_length = l;
+		}
+	}
+
+	auto pwf = taxonomy::make<taxonomy::piecewise_function>();
+	pwf->spans.emplace_back( min_length, composition );
+	pwf->instance = inst;
+	return pwf;
+}
+
+#endif