From Brede Johansen, "I have added "billboardCenter" as a reader option to use the center of

a billboard as the pivot point."

src/osgPlugins/OpenFlight/Document.cpp

@@ -14,6 +14,7 @@ Document::Document() :
     _preserveObject(false),
     _defaultDOFAnimationState(false),
     _useTextureAlphaForTransparancyBinning(true),
+    _useBillboardCenter(false),
     _doUnitsConversion(true),
     _desiredUnits(METERS),
     _done(false),
@@ -38,12 +39,14 @@ Document::~Document()
 void Document::pushLevel()
 {
     _levelStack.push_back(_currentPrimaryRecord.get());
+    _levelStack.back()->pushLevel(*this);
     _level++;
 }
 
 
 void Document::popLevel()
 {
+    _levelStack.back()->popLevel(*this);
     _levelStack.pop_back();
 
     if (!_levelStack.empty())

src/osgPlugins/OpenFlight/Document.h

@@ -150,6 +150,8 @@ class Document
         bool getDefaultDOFAnimationState() const { return _defaultDOFAnimationState; }
         void setUseTextureAlphaForTransparancyBinning(bool flag) { _useTextureAlphaForTransparancyBinning=flag; }
         bool getUseTextureAlphaForTransparancyBinning() const { return _useTextureAlphaForTransparancyBinning; }
+        void setUseBillboardCenter(bool flag) { _useBillboardCenter=flag; }
+        bool getUseBillboardCenter() const { return _useBillboardCenter; }
         void setDoUnitsConversion(bool flag) { _doUnitsConversion=flag; }
         bool getDoUnitsConversion() const { return _doUnitsConversion; }
         void setDesiredUnits(CoordUnits units ) { _desiredUnits=units; }
@@ -166,6 +168,7 @@ class Document
         bool                        _preserveObject;
         bool                        _defaultDOFAnimationState;
         bool                        _useTextureAlphaForTransparancyBinning;
+        bool                        _useBillboardCenter;
         bool                        _doUnitsConversion;
         CoordUnits                  _desiredUnits;
         

src/osgPlugins/OpenFlight/GeometryRecords.cpp

@@ -13,6 +13,7 @@
 #include <osg/PolygonOffset>
 #include <osg/Depth>
 #include <osg/BlendFunc>
+#include <osgUtil/TransformAttributeFunctor>
 #include "Registry.h"
 #include "Document.h"
 #include "RecordInputStream.h"
@@ -416,7 +417,7 @@ protected:
         return osg::PrimitiveSet::POLYGON;
     }
 
-    virtual ~Face()
+    virtual void popLevel(Document& document)
     {
         if (_geode.valid())
         {
@@ -464,6 +465,27 @@ protected:
                     }
                 }
             }
+
+            if (document.getUseBillboardCenter())
+            {
+                // Set billboard rotation point to center of face.
+                osg::Billboard* billboard = dynamic_cast<osg::Billboard*>(_geode.get());
+                if (billboard)
+                {
+                    for (unsigned int i=0; i<billboard->getNumDrawables(); ++i)
+                    {
+                        osg::BoundingBox bb = billboard->getDrawable(i)->getBound();
+                        billboard->setPosition(i,bb.center());
+
+                        osgUtil::TransformAttributeFunctor tf(osg::Matrix::translate(-bb.center()));
+                        billboard->getDrawable(i)->accept(tf);
+
+                        billboard->getDrawable(i)->dirtyBound();
+                    }
+                    
+                    billboard->dirtyBound();
+                }
+            }
         }
     }
 };

src/osgPlugins/OpenFlight/ReaderWriterFLT.cpp

@@ -171,11 +171,14 @@ class FLTReaderWriter : public ReaderWriter
                 document.setDefaultDOFAnimationState((options->getOptionString().find("dofAnimation")!=std::string::npos));
                 osg::notify(osg::DEBUG_INFO) << readerMsg << "dofAnimation=" << document.getDefaultDOFAnimationState() << std::endl;
 
+                document.setUseBillboardCenter((options->getOptionString().find("billboardCenter")!=std::string::npos));
+                osg::notify(osg::DEBUG_INFO) << readerMsg << "billboardCenter=" << document.getUseBillboardCenter() << std::endl;
+
                 document.setUseTextureAlphaForTransparancyBinning(options->getOptionString().find("noTextureAlphaForTransparancyBinning")==std::string::npos);
-                osg::notify(osg::DEBUG_INFO) << readerMsg << "noTextureAlphaForTransparancyBinning=" << document.getUseTextureAlphaForTransparancyBinning() << std::endl;
+                osg::notify(osg::DEBUG_INFO) << readerMsg << "noTextureAlphaForTransparancyBinning=" << !document.getUseTextureAlphaForTransparancyBinning() << std::endl;
 
                 document.setDoUnitsConversion((options->getOptionString().find("noUnitsConversion")==std::string::npos)); // default to true, unless noUnitsConversion is specified.
-                osg::notify(osg::DEBUG_INFO) << readerMsg << "noUnitsConversion=" << document.getDoUnitsConversion() << std::endl;
+                osg::notify(osg::DEBUG_INFO) << readerMsg << "noUnitsConversion=" << !document.getDoUnitsConversion() << std::endl;
 
                 if (document.getDoUnitsConversion())
                 {

src/osgPlugins/OpenFlight/Record.h

@@ -64,6 +64,8 @@ public:
     PrimaryRecord();
 
     virtual void read(RecordInputStream& in, Document& document);
+    virtual void pushLevel(Document& /*document*/) {}
+    virtual void popLevel(Document& /*document*/) {}
 
     // Ancillary operations
     virtual void setID(const std::string& /*id*/) {}