Trade: using `std::unique_ptr` when returning polymorphic types.

This requires inclusion of heavyweight <memory> header (~25k LOC), but
data import isn't something the user would want to do in every file, so
it hopefully won't hurt compilation times too much.

src/Trade/AbstractImporter.cpp

@@ -28,11 +28,14 @@
 #include <Containers/Array.h>
 #include <Utility/Assert.h>
 
+#include "Trade/AbstractMaterialData.h"
 #include "Trade/CameraData.h"
 #include "Trade/ImageData.h"
 #include "Trade/LightData.h"
 #include "Trade/MeshData2D.h"
 #include "Trade/MeshData3D.h"
+#include "Trade/ObjectData2D.h"
+#include "Trade/ObjectData3D.h"
 #include "Trade/SceneData.h"
 #include "Trade/TextureData.h"
 
@@ -209,13 +212,13 @@ std::string AbstractImporter::object2DName(const UnsignedInt id) {
 
 std::string AbstractImporter::doObject2DName(UnsignedInt) { return {}; }
 
-ObjectData2D* AbstractImporter::object2D(const UnsignedInt id) {
+std::unique_ptr<ObjectData2D> AbstractImporter::object2D(const UnsignedInt id) {
     CORRADE_ASSERT(isOpened(), "Trade::AbstractImporter::object2D(): no file opened", {});
     CORRADE_ASSERT(id < doObject2DCount(), "Trade::AbstractImporter::object2D(): index out of range", {});
     return doObject2D(id);
 }
 
-ObjectData2D* AbstractImporter::doObject2D(UnsignedInt) { return nullptr; }
+std::unique_ptr<ObjectData2D> AbstractImporter::doObject2D(UnsignedInt) { return nullptr; }
 
 UnsignedInt AbstractImporter::object3DCount() const {
     CORRADE_ASSERT(isOpened(), "Trade::AbstractImporter::object3DCount(): no file opened", {});
@@ -239,13 +242,13 @@ std::string AbstractImporter::object3DName(const UnsignedInt id) {
 
 std::string AbstractImporter::doObject3DName(UnsignedInt) { return {}; }
 
-ObjectData3D* AbstractImporter::object3D(const UnsignedInt id) {
+std::unique_ptr<ObjectData3D> AbstractImporter::object3D(const UnsignedInt id) {
     CORRADE_ASSERT(isOpened(), "Trade::AbstractImporter::object3D(): no file opened", {});
     CORRADE_ASSERT(id < doObject3DCount(), "Trade::AbstractImporter::object3D(): index out of range", {});
     return doObject3D(id);
 }
 
-ObjectData3D* AbstractImporter::doObject3D(UnsignedInt) { return nullptr; }
+std::unique_ptr<ObjectData3D> AbstractImporter::doObject3D(UnsignedInt) { return nullptr; }
 
 UnsignedInt AbstractImporter::mesh2DCount() const {
     CORRADE_ASSERT(isOpened(), "Trade::AbstractImporter::mesh2DCount(): no file opened", {});
@@ -329,13 +332,13 @@ std::string AbstractImporter::materialName(const UnsignedInt id) {
 
 std::string AbstractImporter::doMaterialName(UnsignedInt) { return {}; }
 
-AbstractMaterialData* AbstractImporter::material(const UnsignedInt id) {
+std::unique_ptr<AbstractMaterialData> AbstractImporter::material(const UnsignedInt id) {
     CORRADE_ASSERT(isOpened(), "Trade::AbstractImporter::material(): no file opened", {});
     CORRADE_ASSERT(id < doMaterialCount(), "Trade::AbstractImporter::material(): index out of range", {});
     return doMaterial(id);
 }
 
-AbstractMaterialData* AbstractImporter::doMaterial(UnsignedInt) { return nullptr; }
+std::unique_ptr<AbstractMaterialData> AbstractImporter::doMaterial(UnsignedInt) { return nullptr; }
 
 UnsignedInt AbstractImporter::textureCount() const {
     CORRADE_ASSERT(isOpened(), "Trade::AbstractImporter::textureCount(): no file opened", {});

src/Trade/AbstractImporter.h

@@ -28,6 +28,7 @@
  * @brief Class Magnum::Trade::AbstractImporter
  */
 
+#include <memory>
 #include <Containers/EnumSet.h>
 #include <PluginManager/AbstractPlugin.h>
 
@@ -240,10 +241,9 @@ class MAGNUM_EXPORT AbstractImporter: public PluginManager::AbstractPlugin {
          * @brief Two-dimensional object
          * @param id        Object ID, from range [0, object2DCount()).
          *
-         * Returns given object or `nullptr` if importing failed. Deleting the
-         * data is user responsibility.
+         * Returns given object or `nullptr` if importing failed.
          */
-        ObjectData2D* object2D(UnsignedInt id);
+        std::unique_ptr<ObjectData2D> object2D(UnsignedInt id);
 
         /** @brief Three-dimensional object count */
         UnsignedInt object3DCount() const;
@@ -268,10 +268,9 @@ class MAGNUM_EXPORT AbstractImporter: public PluginManager::AbstractPlugin {
          * @brief Three-dimensional object
          * @param id        Object ID, from range [0, object3DCount()).
          *
-         * Returns given object or `nullptr` if importing failed. Deleting the
-         * data is user responsibility.
+         * Returns given object or `nullptr` if importing failed.
          */
-        ObjectData3D* object3D(UnsignedInt id);
+        std::unique_ptr<ObjectData3D> object3D(UnsignedInt id);
 
         /** @brief Two-dimensional mesh count */
         UnsignedInt mesh2DCount() const;
@@ -350,10 +349,9 @@ class MAGNUM_EXPORT AbstractImporter: public PluginManager::AbstractPlugin {
          * @brief Material
          * @param id        Material ID, from range [0, materialCount()).
          *
-         * Returns given material or `nullptr` if importing failed. Deleting
-         * the data is user responsibility.
+         * Returns given material or `nullptr` if importing failed.
          */
-        AbstractMaterialData* material(UnsignedInt id);
+        std::unique_ptr<AbstractMaterialData> material(UnsignedInt id);
 
         /** @brief %Texture count */
         UnsignedInt textureCount() const;
@@ -539,7 +537,7 @@ class MAGNUM_EXPORT AbstractImporter: public PluginManager::AbstractPlugin {
         virtual std::string doObject2DName(UnsignedInt id);
 
         /** @brief Implementation for object2D() */
-        virtual ObjectData2D* doObject2D(UnsignedInt id);
+        virtual std::unique_ptr<ObjectData2D> doObject2D(UnsignedInt id);
 
         /** @brief Implementation for object3DCount() */
         virtual UnsignedInt doObject3DCount() const;
@@ -551,7 +549,7 @@ class MAGNUM_EXPORT AbstractImporter: public PluginManager::AbstractPlugin {
         virtual std::string doObject3DName(UnsignedInt id);
 
         /** @brief Implementation for object3D() */
-        virtual ObjectData3D* doObject3D(UnsignedInt id);
+        virtual std::unique_ptr<ObjectData3D> doObject3D(UnsignedInt id);
 
         /** @brief Implementation for mesh2DCount() */
         virtual UnsignedInt doMesh2DCount() const;
@@ -587,7 +585,7 @@ class MAGNUM_EXPORT AbstractImporter: public PluginManager::AbstractPlugin {
         virtual std::string doMaterialName(UnsignedInt id);
 
         /** @brief Implementation for material() */
-        virtual AbstractMaterialData* doMaterial(UnsignedInt id);
+        virtual std::unique_ptr<AbstractMaterialData> doMaterial(UnsignedInt id);
 
         /** @brief Implementation for textureCount() */
         virtual UnsignedInt doTextureCount() const;