Added support for OpenGL mode black listing to provide better support

for extension checking and invalidation of OpenGL modes associated with
extensions.

src/osg/PointSprite.cpp

@@ -16,6 +16,7 @@
 #include <osg/PointSprite>
 #include <osg/State>
 #include <osg/buffered_value>
+#include <osg/Notify>
 
 using namespace osg;
 
@@ -30,6 +31,16 @@ int PointSprite::compare(const StateAttribute& sa) const
     return 0; // passed all the above comparison macro's, must be equal.
 }
 
+
+bool PointSprite::checkValididityOfAssociatedModes(osg::State& state) const
+{
+
+    bool modeValid = isPointSpriteSupported(state.getContextID());
+    state.setModeValidity(GL_POINT_SPRITE_ARB, modeValid);
+
+    return modeValid;
+}
+
 void PointSprite::apply(osg::State& state) const
 {
     if(!isPointSpriteSupported(state.getContextID())) return;

src/osg/State.cpp

@@ -53,7 +53,7 @@ State::~State()
 void State::reset()
 {
 
-/*
+#if 1
     for(ModeMap::iterator mitr=_modeMap.begin();
         mitr!=_modeMap.end();
         ++mitr)
@@ -63,9 +63,10 @@ void State::reset()
         ms.last_applied_value = !ms.global_default_value;
         ms.changed = true;
     }        
-*/
-
+#else
     _modeMap.clear();
+#endif
+
     _modeMap[GL_DEPTH_TEST].global_default_value = true;
     _modeMap[GL_DEPTH_TEST].changed = true;
     

src/osg/StateSet.cpp

@@ -1131,6 +1131,32 @@ const StateSet::RefAttributePair* StateSet::getTextureAttributePair(unsigned int
     return getAttributePair(_textureAttributeList[unit],type,0);
 }
 
+bool StateSet::checkValididityOfAssociatedModes(osg::State& state) const
+{
+
+
+    bool modesValid = true;
+    for(AttributeList::const_iterator itr = _attributeList.begin();
+        itr!=_attributeList.end();
+        ++itr)
+    {
+        if (!itr->second.first->checkValididityOfAssociatedModes(state)) modesValid = false;
+    }
+
+    for(TextureAttributeList::const_iterator taitr=_textureAttributeList.begin();
+        taitr!=_textureAttributeList.end();
+        ++taitr)
+    {
+        for(AttributeList::const_iterator itr = taitr->begin();
+            itr!=taitr->end();
+            ++itr)
+        {
+            if (!itr->second.first->checkValididityOfAssociatedModes(state)) modesValid = false;
+        }
+    }
+
+    return modesValid;
+}
 
 void StateSet::compileGLObjects(State& state) const
 {