First start plug-in architecture

src/ifcgeom/kernels/opencascade/plugin.cpp

@@ -0,0 +1,56 @@
+/********************************************************************************
+ *                                                                              *
+ * 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 "../../kernel_plugin.h"
+#include "OpenCascadeKernel.h"
+
+#include <boost/dll/alias.hpp>
+
+namespace ifcopenshell {
+	namespace geometry {
+		namespace kernels {
+			namespace opencascade_plugin {
+
+				plugin::abi_info plugin_abi() {
+					return plugin::host_abi();
+				}
+
+				plugin::metadata plugin_metadata() {
+					return kernel_plugin_metadata("opencascade");
+				}
+
+				AbstractKernel* create_kernel(ifcopenshell::file*, Settings& settings) {
+					return new IfcGeom::OpenCascadeKernel(settings);
+				}
+
+				void register_plugin(kernel_registry& registry, const plugin::module& module) {
+					kernel_info info;
+					info.backend_id = "opencascade";
+					info.supports_boolean_operations = true;
+					registry.bind(info, create_kernel, module);
+				}
+
+			}
+		}
+	}
+}
+
+BOOST_DLL_ALIAS(ifcopenshell::geometry::kernels::opencascade_plugin::plugin_abi, ifcopenshell_plugin_abi_v1)
+BOOST_DLL_ALIAS(ifcopenshell::geometry::kernels::opencascade_plugin::plugin_metadata, ifcopenshell_plugin_metadata_v1)
+BOOST_DLL_ALIAS(ifcopenshell::geometry::kernels::opencascade_plugin::register_plugin, ifcopenshell_register_kernel_plugin_v1)