From Tim Moore, "I noticed that the "Materials" statistic in the camera scene stats display seemed to be identical to the number of drawables. In fact, it displays the nummat member of osgUtil::Statistics, but that variable has nothing to do with materials. nummat tracks the number of matrices associated with Drawable objects in a RenderBin; as I understand it, Drawables pretty much always have a model-view matrix tied to them in RenderBins, so this statistic doesn't seem very useful. So, I added statistics for the number of StateGraph objects in RenderBins and also for the number of Drawables in the "fine grain ordering" of RenderBins. The latter corresponds to the number of Drawables in the scene that are sorted by some criteria other than graphics state; usually that is distance for semi-transparent objects, though it could be traversal order. These two statistics give an idea of the number of graphic state changes happening in a visible scene: each StateGraph implies a state change, and there could be a change for each sorted object too. You can also subtract the number of sorted Drawables from the total number of Drawables and get an idea of how many Drawables are being drawn for each StateGraph.

"

include/osgUtil/Statistics

@@ -110,6 +110,8 @@ class OSGUTIL_EXPORT Statistics : public osg::PrimitiveFunctor
         void addBins(int np) { nbins+= np; }
 
         void setBinNo(int n) { _binNo=n;}
+        void addStateGraphs(int n) { numStateGraphs += n; }
+        void addOrderedLeaves(int n) { numOrderedLeaves += n; }
         
         void add(const Statistics& stats);
                 
@@ -123,12 +125,13 @@ class OSGUTIL_EXPORT Statistics : public osg::PrimitiveFunctor
         /// deprecated
         PrimitiveCountMap::iterator GetPrimitivesEnd() { return _primitives_count.end(); }
 
-        int numDrawables, nummat, nbins;
+        int numDrawables, nummat, nbins, numStateGraphs;
         int nlights;
         int depth; // depth into bins - eg 1.1,1.2,1.3 etc
         int _binNo;
         StatsType stattype;
         int nimpostor; // number of impostors rendered
+        int numOrderedLeaves;   // leaves from RenderBin fine grain ordering
         
         unsigned int        _vertexCount;
         PrimitiveValueMap    _primitiveCount;

src/osgUtil/RenderBin.cpp

@@ -522,7 +522,7 @@ bool RenderBin::getStats(Statistics& stats) const
 
     // different by return type - collects the stats in this renderrBin
     bool statsCollected = false;
-
+    stats.addOrderedLeaves(_renderLeafList.size());
     // draw fine grained ordering.
     for(RenderLeafList::const_iterator dw_itr = _renderLeafList.begin();
         dw_itr != _renderLeafList.end();
@@ -543,7 +543,7 @@ bool RenderBin::getStats(Statistics& stats) const
         }
         statsCollected = true;
     }
-
+    stats.addStateGraphs(_stateGraphList.size());
     for(StateGraphList::const_iterator oitr=_stateGraphList.begin();
         oitr!=_stateGraphList.end();
         ++oitr)

src/osgUtil/Statistics.cpp

@@ -43,6 +43,8 @@ void Statistics::reset()
     nlights=0;
     nbins=0;
     nimpostor=0;
+    numStateGraphs=0;
+    numOrderedLeaves=0;
 
     _vertexCount=0;
     _primitiveCount.clear();            
@@ -111,6 +113,8 @@ void Statistics::add(const Statistics& stats)
     nlights += stats.nlights;
     nbins += stats.nbins;
     nimpostor += stats.nimpostor;
+    numStateGraphs += stats.numStateGraphs;
+    numOrderedLeaves += stats.numOrderedLeaves;
 
     _vertexCount += stats._vertexCount;
     // _primitiveCount += stats._primitiveCount;   

src/osgViewer/Renderer.cpp

@@ -380,8 +380,9 @@ void Renderer::cull()
             stats->setAttribute(frameNumber, "Visible number of lights", static_cast<double>(sceneStats.nlights));
             stats->setAttribute(frameNumber, "Visible number of render bins", static_cast<double>(sceneStats.nbins));
             stats->setAttribute(frameNumber, "Visible depth", static_cast<double>(sceneStats.depth));
-            stats->setAttribute(frameNumber, "Visible number of materials", static_cast<double>(sceneStats.nummat));
+            stats->setAttribute(frameNumber, "Number of StateGraphs", static_cast<double>(sceneStats.numStateGraphs));
             stats->setAttribute(frameNumber, "Visible number of impostors", static_cast<double>(sceneStats.nimpostor));
+            stats->setAttribute(frameNumber, "Number of ordered leaves", static_cast<double>(sceneStats.numOrderedLeaves));
 
             osgUtil::Statistics::PrimitiveCountMap& pcm = sceneStats.getPrimitiveCountMap();
             stats->setAttribute(frameNumber, "Visible number of GL_POINTS", static_cast<double>(pcm[GL_POINTS]));
@@ -598,8 +599,9 @@ void Renderer::cull_draw()
         stats->setAttribute(frameNumber, "Visible number of lights", static_cast<double>(sceneStats.nlights));
         stats->setAttribute(frameNumber, "Visible number of render bins", static_cast<double>(sceneStats.nbins));
         stats->setAttribute(frameNumber, "Visible depth", static_cast<double>(sceneStats.depth));
-        stats->setAttribute(frameNumber, "Visible number of materials", static_cast<double>(sceneStats.nummat));
+        stats->setAttribute(frameNumber, "Number of StateGraphs", static_cast<double>(sceneStats.numStateGraphs));
         stats->setAttribute(frameNumber, "Visible number of impostors", static_cast<double>(sceneStats.nimpostor));
+        stats->setAttribute(frameNumber, "Number of ordered leaves", static_cast<double>(sceneStats.numOrderedLeaves));
     }
 
 #if 0

src/osgViewer/StatsHandler.cpp

@@ -412,9 +412,10 @@ struct CameraSceneStatsTextDrawCallback : public virtual osg::Drawable::DrawCall
                 STATS_ATTRIBUTE("Visible number of lights")
                 STATS_ATTRIBUTE("Visible number of render bins")
                 STATS_ATTRIBUTE("Visible depth")
-                STATS_ATTRIBUTE("Visible number of materials")
+                STATS_ATTRIBUTE("Number of StateGraphs")
                 STATS_ATTRIBUTE("Visible number of impostors")
                 STATS_ATTRIBUTE("Visible number of drawables")
+                STATS_ATTRIBUTE("Number of ordered leaves")
                 STATS_ATTRIBUTE("Visible vertex count")
 
                 STATS_ATTRIBUTE("Visible number of GL_POINTS")
@@ -1417,9 +1418,10 @@ void StatsHandler::setUpScene(osgViewer::ViewerBase* viewer)
         viewStr << "Lights" << std::endl;
         viewStr << "Bins" << std::endl;
         viewStr << "Depth" << std::endl;
-        viewStr << "Materials" << std::endl;
+        viewStr << "State graphs" << std::endl;
         viewStr << "Imposters" << std::endl;
         viewStr << "Drawables" << std::endl;
+        viewStr << "Sorted" << std::endl;
         viewStr << "Vertices" << std::endl;
         viewStr << "Points" << std::endl;
         viewStr << "Lines" << std::endl;