OpenSceneGraph/examples/osgcallback/osgcallback.cpp

155 lines
4.8 KiB
C++

#include <osgViewer/Viewer>
#include <osg/Transform>
#include <osg/Billboard>
#include <osg/Geode>
#include <osg/Group>
#include <osg/Notify>
#include <osgDB/Registry>
#include <osgDB/ReadFile>
#include <osgGA/TrackballManipulator>
#include <osgGA/FlightManipulator>
#include <osgGA/DriveManipulator>
#include <osgUtil/Optimizer>
#include <iostream>
class UpdateCallback : public osg::NodeCallback
{
virtual void operator()(osg::Node* node, osg::NodeVisitor* nv)
{
std::cout<<"update callback - pre traverse"<<node<<std::endl;
traverse(node,nv);
std::cout<<"update callback - post traverse"<<node<<std::endl;
}
};
class CullCallback : public osg::NodeCallback
{
virtual void operator()(osg::Node* node, osg::NodeVisitor* nv)
{
std::cout<<"cull callback - pre traverse"<<node<<std::endl;
traverse(node,nv);
std::cout<<"cull callback - post traverse"<<node<<std::endl;
}
};
class DrawableDrawCallback : public osg::Drawable::DrawCallback
{
virtual void drawImplementation(osg::RenderInfo& renderInfo,const osg::Drawable* drawable) const
{
std::cout<<"draw call back - pre drawImplementation"<<drawable<<std::endl;
drawable->drawImplementation(renderInfo);
std::cout<<"draw call back - post drawImplementation"<<drawable<<std::endl;
}
};
struct DrawableUpdateCallback : public osg::Drawable::UpdateCallback
{
virtual void update(osg::NodeVisitor*, osg::Drawable* drawable)
{
std::cout<<"Drawable update callback "<<drawable<<std::endl;
}
};
struct DrawableCullCallback : public osg::Drawable::CullCallback
{
/** do customized cull code.*/
virtual bool cull(osg::NodeVisitor*, osg::Drawable* drawable, osg::State* /*state*/) const
{
std::cout<<"Drawable cull callback "<<drawable<<std::endl;
return false;
}
};
class InsertCallbacksVisitor : public osg::NodeVisitor
{
public:
InsertCallbacksVisitor():osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN)
{
}
virtual void apply(osg::Node& node)
{
node.setUpdateCallback(new UpdateCallback());
node.setCullCallback(new CullCallback());
traverse(node);
}
virtual void apply(osg::Geode& geode)
{
geode.setUpdateCallback(new UpdateCallback());
//note, it makes no sense to attach a cull callback to the node
//at there are no nodes to traverse below the geode, only
//drawables, and as such the Cull node callbacks is ignored.
//If you wish to control the culling of drawables
//then use a drawable cullback...
for(unsigned int i=0;i<geode.getNumDrawables();++i)
{
geode.getDrawable(i)->setUpdateCallback(new DrawableUpdateCallback());
geode.getDrawable(i)->setCullCallback(new DrawableCullCallback());
geode.getDrawable(i)->setDrawCallback(new DrawableDrawCallback());
}
}
virtual void apply(osg::Transform& node)
{
apply((osg::Node&)node);
}
};
class MyReadFileCallback : public osgDB::Registry::ReadFileCallback
{
public:
virtual osgDB::ReaderWriter::ReadResult readNode(const std::string& fileName, const osgDB::ReaderWriter::Options* options)
{
std::cout<<"before readNode"<<std::endl;
// note when calling the Registry to do the read you have to call readNodeImplementation NOT readNode, as this will
// cause on infinite recusive loop.
osgDB::ReaderWriter::ReadResult result = osgDB::Registry::instance()->readNodeImplementation(fileName,options);
std::cout<<"after readNode"<<std::endl;
return result;
}
};
int main( int argc, char **argv )
{
// use an ArgumentParser object to manage the program arguments.
osg::ArgumentParser arguments(&argc,argv);
// set the osgDB::Registy the read file callback to catch all requests for reading files.
osgDB::Registry::instance()->setReadFileCallback(new MyReadFileCallback());
// initialize the viewer.
osgViewer::Viewer viewer;
// load the nodes from the commandline arguments.
osg::Node* rootnode = osgDB::readNodeFiles(arguments);
if (!rootnode)
{
osg::notify(osg::NOTICE)<<"Please specify a file on the command line"<<std::endl;
return 1;
}
// run optimization over the scene graph
osgUtil::Optimizer optimzer;
optimzer.optimize(rootnode);
// insert all the callbacks
InsertCallbacksVisitor icv;
rootnode->accept(icv);
// set the scene to render
viewer.setSceneData(rootnode);
return viewer.run();
}