forcing users to use osgDB::readRef*File() methods. The later is preferable as it closes a potential threading bug when using paging databases in conjunction
with the osgDB::Registry Object Cache. This threading bug occurs when one thread gets an object from the Cache via an osgDB::read*File() call where only
a pointer to the object is passed back, so taking a reference to the object is delayed till it gets reassigned to a ref_ptr<>, but at the same time another
thread calls a flush of the Object Cache deleting this object as it's referenceCount is now zero. Using osgDB::readREf*File() makes sure the a ref_ptr<> is
passed back and the referenceCount never goes to zero.
To ensure the OSG builds when OSG_PROVIDE_READFILE is to OFF the many cases of osgDB::read*File() usage had to be replaced with a ref_ptr<> osgDB::readRef*File()
usage. The avoid this change causing lots of other client code to be rewritten to handle the use of ref_ptr<> in place of C pointer I introduced a serious of
templte methods in various class to adapt ref_ptr<> to the underly C pointer to be passed to old OSG API's, example of this is found in include/osg/Group:
bool addChild(Node* child); // old method which can only be used with a Node*
tempalte<class T> bool addChild(const osg::ref_ptr<T>& child) { return addChild(child.get()); } // adapter template method
These changes together cover 149 modified files, so it's a large submission. This extent of changes are warrent to make use of the Object Cache
and multi-threaded loaded more robust.
git-svn-id: http://svn.openscenegraph.org/osg/OpenSceneGraph/trunk@15164 16af8721-9629-0410-8352-f15c8da7e697
1. Rewrite the reading/writing exception handlers to work like the ive
plugin exceptions.
2. Write a header writing/checking function in ReaderWriterOSG2.cpp,
which may help decide if the stream is ascii or binary. The
readInputIterator() function will return null pointer if the input
file is nither osgb nor osgt format, which indicates that the old .osg
format could be used here, in case we've merged the two plugins
together.
3. Add a new ForceReadingImage option in the InputStream, which will
allocate an empty image object with the filename if specifed external
image file is missed. It may be useful for format converting in some
cases.
4. Add new osgParticle wrappers, as well as some modification to the
osgParticle headers, for instance, change isEnabled() to getEnabled().
5. Some fixes to the osg serialization wrappers."
From Robert Osfield, refactor of Wang Rui's original osg2 into 3 parts - parts placed into osgDB, the ReaderWriter placed into src/osg/Plugin/osg and wrappers into src/osgWrappers/serializers/osg
