Fixes for osgFX.

examples/osgpagedlod/osgpagedlod.cpp

@@ -0,0 +1,156 @@
+#include <osg/Group>
+#include <osg/Notify>
+#include <osg/Geometry>
+#include <osg/ArgumentParser>
+#include <osg/ApplicationUsage>
+#include <osg/Texture2D>
+#include <osg/Geode>
+#include <osg/PagedLOD>
+
+#include <osgDB/Registry>
+#include <osgDB/ReadFile>
+#include <osgDB/WriteFile>
+
+#include <osgUtil/Optimizer>
+
+osg::Geode* createTile(const osg::Vec3& lb, const osg::Vec3& rb,
+                       const osg::Vec3& lt, const osg::Vec3& rt,
+                       const std::string& imageFile)
+{
+
+    // create the geometry.
+    osg::Geometry* geom = new osg::Geometry;
+
+    osg::Vec3Array* coords = new osg::Vec3Array(4);
+    (*coords)[0] = lt;
+    (*coords)[1] = lb;
+    (*coords)[2] = rb;
+    (*coords)[3] = rt;
+    geom->setVertexArray(coords);
+
+    osg::Vec2Array* tcoords = new osg::Vec2Array(4);
+    (*tcoords)[0].set(0.0f,1.0f);
+    (*tcoords)[1].set(0.0f,0.0f);
+    (*tcoords)[2].set(1.0f,0.0f);
+    (*tcoords)[3].set(1.0f,1.0f);
+    geom->setTexCoordArray(0,tcoords);
+
+    osg::Vec4Array* colours = new osg::Vec4Array(1);
+    (*colours)[0].set(1.0f,1.0f,1.0,1.0f);
+    geom->setColorArray(colours);
+    geom->setColorBinding(osg::Geometry::BIND_OVERALL);
+
+    osg::Vec3Array* normals = new osg::Vec3Array(1);
+    (*normals)[0] = (rb-lb)^(lt-lb);
+    (*normals)[0].normalize();
+    geom->setNormalArray(normals);
+    geom->setNormalBinding(osg::Geometry::BIND_OVERALL);
+
+    geom->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,0,4));
+    
+    
+    // add the texture to the geometry.
+    geom->getOrCreateStateSet()->setTextureAttributeAndModes(
+        0, // texture unit 0.
+        new osg::Texture2D(osgDB::readImageFile(imageFile)),
+        osg::StateAttribute::ON);
+    
+    
+    // create the geode.
+    osg::Geode* geode = new osg::Geode;
+    geode->addDrawable(geom);
+    
+    return geode;
+
+}
+
+
+osg::Node* createPagedModel()
+{
+    osg::PagedLOD* level_0 = new osg::PagedLOD;
+
+    float distance = 1000.0f;
+    
+    osg::Vec3 lb(0.0f,0.0f,0.0f);
+    osg::Vec3 rb(distance,0.0f,0.0f);
+    osg::Vec3 rt(distance,0.0f,distance);
+    osg::Vec3 lt(0.0f,0.0f,distance);
+    
+    level_0->addChild(createTile(lb,rb,lt,rt,"lz.rgb"),distance,1e5,"");
+    level_0->addChild(createTile(lb,rb,lt,rt,"land_shallow_topo_2048.jpg"),0,distance,"level_1.osg");
+
+    return level_0;    
+}
+
+class WriteOutPagedLODSubgraphsVistor : public osg::NodeVisitor
+{
+public:
+    WriteOutPagedLODSubgraphsVistor():
+        osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN)
+    {
+    }
+    
+    virtual void apply(osg::PagedLOD& plod)
+    {
+        // go through all the named children and write them out to disk.
+        for(unsigned int i=0;i<plod.getNumChildren();++i)
+        {
+            osg::Node* child = plod.getChild(i);
+            std::string filename = plod.getFileName(i);
+            if (!filename.empty()) osgDB::writeNodeFile(*child,filename);
+        }
+    
+        traverse(plod);
+    }    
+};
+
+
+
+int main( int argc, char **argv )
+{
+
+    // use an ArgumentParser object to manage the program arguments.
+    osg::ArgumentParser arguments(&argc,argv);
+    
+    // set up the usage document, in case we need to print out how to use this program.
+    arguments.getApplicationUsage()->setApplicationName(arguments.getApplicationName());
+    arguments.getApplicationUsage()->setDescription(arguments.getApplicationName()+" creates a hierachy of files for paging which can be later loaded by viewers.");
+    arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+" [options] filename ...");
+    arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display this information");
+
+    // if user request help write it out to cout.
+    if (arguments.read("-h") || arguments.read("--help"))
+    {
+        arguments.getApplicationUsage()->write(std::cout);
+        return 1;
+    }
+
+    // any option left unread are converted into errors to write out later.
+    arguments.reportRemainingOptionsAsUnrecognized();
+
+    // report any errors if they have occured when parsing the program aguments.
+    if (arguments.errors())
+    {
+        arguments.writeErrorMessages(std::cout);
+        return 1;
+    }
+    
+//     if (arguments.argc()<=1)
+//     {
+//         arguments.getApplicationUsage()->write(std::cout,osg::ApplicationUsage::COMMAND_LINE_OPTION);
+//         return 1;
+//     }
+
+
+    osg::ref_ptr<osg::Node> model = createPagedModel();
+    
+    if (model.valid())
+    {
+        osgDB::writeNodeFile(*model,"level_0.osg");
+        
+        WriteOutPagedLODSubgraphsVistor woplsv;
+        model->accept(woplsv);
+    }
+
+    return 0;
+}