Added support for automatic creation of global StateAttributes to osg::State,

these global attributes are created by cloning any attributes which are
applied during rendering, the clone in a shallow copy, which will set up
default valus for that attribute.  This should prevent attribute bleed
from one stateset to the next when the global StateSet doesn't contain
an attribute used within the scene graph.

src/osg/State.cpp

@@ -8,7 +8,6 @@ using namespace osg;
 State::State()
 {
     _contextID = 0;
-    _fineGrainedErrorDetection = true;
 }
 
 State::~State()
@@ -17,8 +16,34 @@ State::~State()
 
 void State::reset()
 {
+/*
+    for(ModeMap::iterator mitr=_modeMap.begin();
+        mitr!=_modeMap.end();
+        ++mitr)
+    {
+        ModeStack& ms = mitr->second;
+        ms.valueVec.clear();
+        ms.last_applied_value = !ms.global_default_value;
+        ms.changed = true;
+    }        
+*/
+
     _modeMap.clear();
-    _attributeMap.clear();
+    _modeMap[GL_DEPTH_TEST].global_default_value = true;
+
+    // go through all active StateAttribute's, applying where appropriate.
+    for(AttributeMap::iterator aitr=_attributeMap.begin();
+        aitr!=_attributeMap.end();
+        ++aitr)
+    {
+        AttributeStack& as = aitr->second;
+        as.attributeVec.clear();
+        as.last_applied_attribute = NULL;
+        as.changed = true;
+    }        
+
+//    _attributeMap.clear();
+
     _drawStateStack.clear();
 }
 
@@ -172,7 +197,7 @@ void State::apply(const StateSet* dstate)
                         else
                         {
                             // assume default of disabled.
-                            apply_mode(this_mitr->first,false,ms);
+                            apply_mode(this_mitr->first,ms.global_default_value,ms);
 
                         }
             
@@ -249,7 +274,7 @@ void State::apply(const StateSet* dstate)
                     else
                     {
                         // assume default of disabled.
-                        apply_mode(this_mitr->first,false,ms);
+                        apply_mode(this_mitr->first,ms.global_default_value,ms);
 
                     }
             
@@ -297,9 +322,7 @@ void State::apply(const StateSet* dstate)
                         }
                         else
                         {
-                            // this is really an error state, in theory we *should* have a
-                            // global state attribute set for all types.
-                            //notify(WARN)<<"    No global StateAttribute set for type"<<(int)aitr->first<<endl;
+                            apply_global_default_attribute(as);
                         }
                     }
 
@@ -372,9 +395,7 @@ void State::apply(const StateSet* dstate)
                     }
                     else
                     {
-                        // this is really an error state, in theory we *should* have a
-                        // global state attribute set for all types.
-                        //notify(WARN)<<"    No global StateAttribute set for type"<<(int)aitr->first<<endl;
+                        apply_global_default_attribute(as);
                     }
                 }
             }        
@@ -427,7 +448,7 @@ void State::apply()
             else
             {
                 // assume default of disabled.
-                apply_mode(mitr->first,false,ms);
+                apply_mode(mitr->first,ms.global_default_value,ms);
             }
             
         }
@@ -449,9 +470,7 @@ void State::apply()
             }
             else
             {
-                // this is really an error state, in theory we *should* have a
-                // global state attribute set for all types.
-                //notify(WARN)<<"    No global StateAttribute set for type"<<(int)aitr->first<<endl;
+                apply_global_default_attribute(as);
             }
             
         }