Refactored the subsurface PolygonOffset code so that it uses sensible values and also moves management of the PolygonOffset and Depth attribute objects into the Document object rather than using static vars.

src/osgPlugins/OpenFlight/Document.cpp

@@ -45,6 +45,7 @@ Document::Document() :
     _lightPointAnimationPoolParent(false),
     _shaderPoolParent(false)
 {
+    _subsurfaceDepth = new osg::Depth(osg::Depth::LESS, 0.0, 1.0,false);
 }
 
 Document::~Document()
@@ -110,6 +111,22 @@ osg::Node* Document::getInstanceDefinition(int no)
     return NULL;
 }
 
+void Document::setSubSurfacePolygonOffset(int level, osg::PolygonOffset* po)
+{
+    _subsurfacePolygonOffsets[level] = po;
+}
+
+osg::PolygonOffset* Document::getSubSurfacePolygonOffset(int level)
+{
+    osg::notify(osg::DEBUG_INFO)<<"Document::getSubSurfacePolygonOffset("<<level<<")"<<std::endl;
+    osg::ref_ptr<osg::PolygonOffset>& po = _subsurfacePolygonOffsets[level];
+    if (!po)
+    {
+        po = new osg::PolygonOffset(-1.0f*float(level), -1.0f);
+    }
+    return po.get();
+}
+
 double flt::unitsToMeters(CoordUnits unit)
 {
     switch (unit)

src/osgPlugins/OpenFlight/Document.h

@@ -24,6 +24,8 @@
 #include <osg/Notify>
 #include <osg/Transform>
 #include <osg/Geometry>
+#include <osg/PolygonOffset>
+#include <osg/Depth>
 #include <osgDB/ReaderWriter>
 
 #include "Types.h"
@@ -166,6 +168,12 @@ class Document
         ShaderPool* getOrCreateShaderPool();
         bool getShaderPoolParent() const { return _shaderPoolParent; }
 
+        void setSubSurfacePolygonOffset(int level, osg::PolygonOffset* po);
+        osg::PolygonOffset* getSubSurfacePolygonOffset(int level);
+
+        void setSubSurfaceDepth(osg::Depth* depth) { _subsurfaceDepth = depth; }
+        osg::Depth* getSubSurfaceDepth() { return _subsurfaceDepth.get(); }
+
 
         // Options
         void setReplaceClampWithClampToEdge(bool flag) { _replaceClampWithClampToEdge = flag; }
@@ -225,6 +233,11 @@ class Document
         osg::ref_ptr<LightPointAppearancePool> _lightPointAppearancePool;
         osg::ref_ptr<LightPointAnimationPool> _lightPointAnimationPool;
         osg::ref_ptr<ShaderPool> _shaderPool;
+
+        typedef std::map<int, osg::ref_ptr<osg::PolygonOffset> > SubSurfacePolygonOffsets;
+        SubSurfacePolygonOffsets _subsurfacePolygonOffsets;
+        osg::ref_ptr<osg::Depth> _subsurfaceDepth;
+
         bool _colorPoolParent;
         bool _texturePoolParent;
         bool _materialPoolParent;

src/osgPlugins/OpenFlight/GeometryRecords.cpp

@@ -23,8 +23,6 @@
 #include <osg/Geometry>
 #include <osg/Texture2D>
 #include <osg/CullFace>
-#include <osg/PolygonOffset>
-#include <osg/Depth>
 #include <osg/BlendFunc>
 #include <osgUtil/TransformAttributeFunctor>
 #include "Registry.h"
@@ -383,28 +381,12 @@ protected:
         // Subface
         if (document.subfaceLevel() > 0)
         {
-            static osg::ref_ptr<osg::PolygonOffset> polygonOffset = new osg::PolygonOffset(-10.0f, -40.0f);
+            stateset->setAttributeAndModes(document.getSubSurfacePolygonOffset(document.subfaceLevel()), osg::StateAttribute::ON);
-            stateset->setAttributeAndModes(polygonOffset.get(), osg::StateAttribute::ON);
+            stateset->setAttribute(document.getSubSurfaceDepth());
-
-            static osg::ref_ptr<osg::Depth> depth = new osg::Depth(osg::Depth::LESS, 0.0, 1.0,false);
-            stateset->setAttribute(depth.get());
 
             stateset->setRenderBinDetails(document.subfaceLevel(),"RenderBin");
         }
 
-#if 0
-// note from Robert Osfield, this "optimization" breaks multi-textured datasets that mix single texture 
-// and mulit-texture geometries as the Multitexture parsing can come after the below code, and accidentally 
-// polute the non multi-texture geometries StateSet.
-
-        // A simple share stateset optimization.
-        static osg::ref_ptr<osg::StateSet> lastStateset;
-        if (lastStateset.valid() && (stateset->compare(*lastStateset,false)==0))
-            stateset = lastStateset;
-        else
-            lastStateset = stateset;
-#endif
-
         _geode->setStateSet(stateset.get());
 
         // Add to parent.
@@ -952,28 +934,12 @@ protected:
         // Subface
         if (document.subfaceLevel() > 0)
         {
-            static osg::ref_ptr<osg::PolygonOffset> polygonOffset = new osg::PolygonOffset(-10.0f, -40.0f);
+            stateset->setAttributeAndModes(document.getSubSurfacePolygonOffset(document.subfaceLevel()), osg::StateAttribute::ON);
-            stateset->setAttributeAndModes(polygonOffset.get(), osg::StateAttribute::ON);
+            stateset->setAttribute(document.getSubSurfaceDepth());
-
-            static osg::ref_ptr<osg::Depth> depth = new osg::Depth(osg::Depth::LESS, 0.0, 1.0,false);
-            stateset->setAttribute(depth.get());
 
             stateset->setRenderBinDetails(document.subfaceLevel(),"RenderBin");
         }
 
-#if 0
-// note from Robert Osfield, this "optimization" breaks multi-textured datasets that mix single texture 
-// and mulit-texture geometries as the Multitexture parsing can come after the below code, and accidentally 
-// polute the non multi-texture geometries StateSet.
-
-        // A simple share stateset optimization.
-        static osg::ref_ptr<osg::StateSet> lastStateset;
-        if (lastStateset.valid() && (stateset->compare(*lastStateset,false)==0))
-            stateset = lastStateset;
-        else
-            lastStateset = stateset;
-#endif
-
         _geode->setStateSet(stateset.get());
 
         // Add to parent.