Some basic code to lookup lengths for pre ADD2 schemas

src/ifcgeom/ConversionSettings.h

@@ -187,6 +187,13 @@ namespace ifcopenshell {
 				static constexpr bool defaultvalue = false;
 			};
 
+			struct UseMaterialNames : public SettingBase<UseMaterialNames, bool> {
+				static constexpr const char* const name = "use-material-names";
+				static constexpr const char* const description = "Use material names instead of unique IDs for naming materials upon serialization. "
+					"Applicable for OBJ and DAE output.";
+				static constexpr bool defaultvalue = false;
+			};
+
 			struct ConvertBackUnits : public SettingBase<ConvertBackUnits, bool> {
 				static constexpr const char* const name = "convert-back-units";
 				static constexpr const char* const description = "Specifies whether to convert back geometrical output back to the "
@@ -433,7 +440,7 @@ namespace ifcopenshell {
 		};
 
 		class IFC_GEOM_API Settings : public SettingsContainer<
-                                          std::tuple<MesherLinearDeflection, MesherAngularDeflection, ReorientShells, LengthUnit, PlaneUnit, Precision, OutputDimensionality, LayersetFirst, DisableBooleanResult, NoWireIntersectionCheck, NoWireIntersectionTolerance, PrecisionFactor, DebugBooleanOperations, BooleanAttempt2d, WeldVertices, UseWorldCoords, ConvertBackUnits, ContextIds, ContextTypes, ContextIdentifiers, IteratorOutput, DisableOpeningSubtractions, ApplyDefaultMaterials, DontEmitNormals, GenerateUvs, ApplyLayerSets, UseElementHierarchy, ValidateQuantities, EdgeArrows, BuildingLocalPlacement, SiteLocalPlacement, ForceSpaceTransparency, CircleSegments, KeepBoundingBoxes, PiecewiseStepType, PiecewiseStepParam>
+                                          std::tuple<MesherLinearDeflection, MesherAngularDeflection, ReorientShells, LengthUnit, PlaneUnit, Precision, OutputDimensionality, LayersetFirst, DisableBooleanResult, NoWireIntersectionCheck, NoWireIntersectionTolerance, PrecisionFactor, DebugBooleanOperations, BooleanAttempt2d, WeldVertices, UseWorldCoords, UseMaterialNames, ConvertBackUnits, ContextIds, ContextTypes, ContextIdentifiers, IteratorOutput, DisableOpeningSubtractions, ApplyDefaultMaterials, DontEmitNormals, GenerateUvs, ApplyLayerSets, UseElementHierarchy, ValidateQuantities, EdgeArrows, BuildingLocalPlacement, SiteLocalPlacement, ForceSpaceTransparency, CircleSegments, KeepBoundingBoxes, PiecewiseStepType, PiecewiseStepParam>
 		>
 		{};
 }

src/ifcgeom/GeometrySerializer.h

@@ -49,13 +49,6 @@ inline namespace settings {
 		static constexpr bool defaultvalue = false;
 	};
 
-	struct UseMaterialNames : public SettingBase<UseMaterialNames, bool> {
-		static constexpr const char* const name = "use-material-names";
-		static constexpr const char* const description = "Use material names instead of unique IDs for naming materials upon serialization. "
-					"Applicable for OBJ and DAE output.";
-		static constexpr bool defaultvalue = false;
-	};
-
 	struct UseElementTypes : public SettingBase<UseElementTypes, bool> {
 		static constexpr const char* const name = "use-element-types";
 		static constexpr const char* const description = "Use element types instead of unique IDs for naming elements upon serialization. "

src/ifcgeom/mapping/IfcCurveSegment.cpp

@@ -50,6 +50,35 @@ enum segment_type_t {
 // @todo use std::numbers::pi when upgrading to C++ 20
 static const double PI = boost::math::constants::pi<double>();
 
+
+namespace {
+    double translate_to_length_measure(const IfcSchema::IfcCurve* crv, double param_value) {
+        if (std::abs(param_value) < 1.e-7) {
+            return param_value;
+        } else if (crv->as<IfcSchema::IfcLine>()) {
+            // @todo we should actually check magnitude of the vector
+            return param_value;
+        } else if (crv->as<IfcSchema::IfcClothoid>()) {
+            // @todo this is wrong.
+            return param_value;
+        } else if (auto circ = crv->as<IfcSchema::IfcCircle>()) {
+            return circ->Radius() * param_value;
+        } else {
+            throw std::runtime_error("Unsupported curve measure type");
+        }
+    }
+
+    double translate_if_param_value(const IfcSchema::IfcCurve* crv, IfcSchema::IfcCurveMeasureSelect* val) {
+        if (auto param = val->as<IfcSchema::IfcParameterValue>()) {
+            // We don't care whether length- or positive length measure.
+            return translate_to_length_measure(crv, *param);
+        } else {
+            return *val->data().getArgument(0);
+        }
+    }
+}
+
+
 // Current implementation uses the same segment_geometry_adjuster for all ParentCurve types.
 // Comment/Uncomment to change the type of segment geometry adjuster
 // Future implementations could use specialized adjusters based on ParentCurve type