Introduce AbstractKernel

src/ifcgeom/schema_agnostic/ConversionResult.h

@@ -34,6 +34,7 @@ namespace IfcGeom {
 	public:
 		virtual void Multiply(const ConversionResultPlacement*) = 0;
 		virtual void PreMultiply(const ConversionResultPlacement*) = 0;
+		virtual void TranslationPart(double& X, double& Y, double& Z) const = 0;
 		virtual ConversionResultPlacement* inverted() const = 0;
 		virtual ConversionResultPlacement* multiplied(const ConversionResultPlacement*) const = 0;
 		virtual double Value(int i, int j) const = 0;

src/ifcgeom/schema_agnostic/Kernel.h

@@ -72,7 +72,7 @@ namespace IfcGeom {
 			return implementation_->convert(item);
 		}
 
-		virtual bool convert_placement(IfcUtil::IfcBaseClass* item, gp_Trsf& trsf) {
+		virtual bool convert_placement(IfcUtil::IfcBaseClass* item, ConversionResultPlacement*& trsf) {
 			return implementation_->convert_placement(item, trsf);
 		}
 

src/ifcgeom/schema_agnostic/cgal/CgalConversionResult.h

@@ -66,6 +66,10 @@ namespace IfcGeom {
 		virtual ConversionResultPlacement* multiplied(const ConversionResultPlacement*) const {
 			throw std::runtime_error("Not implemented");
 		}
+
+		virtual void TranslationPart(double& X, double& Y, double& Z) const {
+			throw std::runtime_error("Not implemented");
+		}
     private:
         cgal_placement_t trsf_;
     };

src/ifcgeom/schema_agnostic/opencascade/OpenCascadeConversionResult.h

@@ -69,6 +69,12 @@ namespace IfcGeom {
 		virtual ConversionResultPlacement* multiplied(const ConversionResultPlacement* other) const {
 			return new OpenCascadePlacement(trsf_.Multiplied(((OpenCascadePlacement*)other)->trsf_));
 		}
+
+		virtual void TranslationPart(double& X, double& Y, double& Z) const {
+			X = trsf_.TranslationPart().X();
+			Y = trsf_.TranslationPart().Y();
+			Z = trsf_.TranslationPart().Z();
+		}
     private:
         gp_GTrsf trsf_;
     };