Hi Chuck, Thanks for the useful information. Hope it could be added to the wiki page, as a good supplement of my origin serializer tutorial which is written unpolished and in a hurry. :)
I'm still waiting for decision of the submitted osgAnimation serializers. After that I'll continue completing other core library wrappers and have a taste to support the introspection mechanism, which would be a lightweight replacement of osgIntrospection. Cheers, Wang Rui 2010/4/16 Chuck Seberino <[email protected]>: > I have been playing around with the new serialization support with 2.9.7 and > wanted to share some of my findings. I think some of these might be useful > for others looking to do the same. > > 1. Serialization support *requires* that you override the virtual methods > for className() and libraryName(). If you don't, then things won't > serialize properly and you might spend *LOTS* of time trying to figure out > why... > 2. You can provide serialization for a class that doesn't live in a > namespace. Just specify global namespace. > > REGISTER_OBJECT_WRAPPER(NoNamespaceClass, > new NoNamespaceClass, > ::NoNamespaceClass, > "osg::Object osg::Node ::NoNamespaceClass") { ... } > > 3. As long as you have item 1. you can still serialize a class without > adding in additional accessors and mutators. This is useful if you have a > class that you can't or don't want to change to add in the necessary set/get > methods to satisfy serialization. A wrapper class can be created to do this > for you. > > // Class that we don't want to expose get/set > > class NoGetSetClass : public osg::Node > { > public: > > ... > virtual const char* className() const { return "NoGetSetClass"; } // name > to match > virtual const char* libraryName() const { return ""; } // no > namespace > protected: > std::string _internalVariable; > }; > > // Helper class that is used just for serialization purposes > class SerializerForNoGetSetClass : public NoGetSetClass > { > public: > > ... > const std::string& getVariable() const { return _internalVariable; } > void setVariable(const std::string& str) { _internalVariable = str; } > }; > > REGISTER_OBJECT_WRAPPER(NoGetSetClass, // Old name because > this is what we match against > > new SerializerForNoGetSetClass, // Use helper class > for get/set > > ::NoGetSetClass, > > "osg::Object osg::Node ::NoGetSetClass") > > { > > // Manually recreate macro to specify our serializer subclass > > wrapper->addSerializer(new > osgDB::StringSerializer<SerializerForNoGetSetClass>("Variable", "default", > &SerializerForNoGetSetClass::getVariable, > &SerializerForNoGetSetClass::setVariable)); > } > > The macros for ADD_*_SERIALIZER can't be used because we want to use our > subclass instead of the original class we want serialized. When the > serialization code is invoked, it matches the class type and classname > properly with the old class, but constructs an instance of > SerializerForNoGetSetClass to push and pull values. > 4. You can specify more than one REGISTER_OBJECT_WRAPPER statement in a > single compilation unit. The macro creates a typedef (typedef CLASS > MyClass) that is used for the subsequent serialization commands. Calling > the macro more than once will cause it to complain about the redefinition of > MyClass. Since the purpose of the macro is to statically register a > wrapper, it can be guarded by a namespace and still function just fine. > > // This macro creates a typedef > > REGISTER_OBJECT_WRAPPER(Class1, > > new Class1, > > ::Class1, > > "osg::Object ::Class1") > { > > // We only require the typedef to be valid in here > ... > } > > // The typedef is still available here > > namespace { // Now this macro doesn't conflict with previous macro typedef > REGISTER_OBJECT_WRAPPER(Class2, > > new Class2, > > ::Class2, > > "osg::Object ::Class2") > { > ... > > // The new typedef takes precedence because of namespace scope > } > } // namespace > > > > Hopefully these nuggets of information will help anyone else trying to get > their own custom classes to serialize properly without pulling out too much > hair. For those that don't know it, this wiki link is a good starting point > http://www.openscenegraph.org/projects/osg/wiki/Support/KnowledgeBase/SerializationSupport > > Regards, > Chuck Seberino > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
