From 93a2c3d0119909a75adfc4c912dc4ddeefc0d67f Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Mon, 16 Jan 2006 17:05:17 +0000
Subject: [PATCH] Improved handling of clean up of osg::Program/osg::Shader on
 closing of a graphis context.

---
 include/osg/Program       |  2 +-
 include/osg/Shader        |  5 +++++
 src/osg/Program.cpp       | 20 ++++++++++++++++----
 src/osg/Shader.cpp        | 10 ++++++++++
 src/osgUtil/SceneView.cpp |  3 +++
 5 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/include/osg/Program b/include/osg/Program
index c608f388f..8a32ce060 100644
--- a/include/osg/Program
+++ b/include/osg/Program
@@ -132,7 +132,7 @@ class OSG_EXPORT Program : public osg::StateAttribute
 
                 void requestLink();
                 void linkProgram();
-                void validateProgram();
+                bool validateProgram();
                 bool needsLink() const {return _needsLink;}
                 bool isLinked() const {return _isLinked;}
                 bool getInfoLog( std::string& infoLog ) const;
diff --git a/include/osg/Shader b/include/osg/Shader
index ea066b8d9..9d5f42a8b 100644
--- a/include/osg/Shader
+++ b/include/osg/Shader
@@ -81,6 +81,11 @@ class OSG_EXPORT Shader : public osg::Object
         /** Get the Shader type as a descriptive string. */
         const char* getTypename() const;
 
+        /** release OpenGL objects in specified graphics context if State
+            object is passed, otherwise release OpenGL objects for all graphics context if
+            State object pointer NULL.*/
+        void releaseGLObjects(osg::State* state=0) const;
+
         /** Mark our PCSs as needing recompilation.
           * Also mark Programs that depend on us as needing relink */
         void dirtyShader();        
diff --git a/src/osg/Program.cpp b/src/osg/Program.cpp
index 08f9af318..8ab42ad73 100644
--- a/src/osg/Program.cpp
+++ b/src/osg/Program.cpp
@@ -1999,9 +1999,19 @@ void Program::dirtyProgram()
 }
 
 
-void Program::releaseGLObjects(osg::State* /*state*/) const
+void Program::releaseGLObjects(osg::State* state) const
 {
-    // TODO
+    for( unsigned int i=0; i < _shaderList.size(); ++i )
+    {
+        if (_shaderList[i].valid()) _shaderList[i]->releaseGLObjects(state);
+    }
+
+    if (!state) _pcpList.setAllElementsTo(0);
+    else
+    {
+        unsigned int contextID = state->getContextID();
+        _pcpList[contextID] = 0;
+    }   
 }
 
 
@@ -2274,13 +2284,13 @@ void Program::PerContextProgram::linkProgram()
     osg::notify(osg::INFO) << std::endl;
 }
 
-void Program::PerContextProgram::validateProgram()
+bool Program::PerContextProgram::validateProgram()
 {
     GLint validated = GL_FALSE;
     _extensions->glValidateProgram( _glProgramHandle );
     _extensions->glGetProgramiv( _glProgramHandle, GL_VALIDATE_STATUS, &validated );
     if( validated == GL_TRUE)
-        return;
+        return true;
 
     osg::notify(osg::INFO)
         << "glValidateProgram FAILED \"" << _program->getName() << "\""
@@ -2293,6 +2303,8 @@ void Program::PerContextProgram::validateProgram()
         osg::notify(osg::INFO) << "infolog:\n" << infoLog << std::endl;
 
     osg::notify(osg::INFO) << std::endl;
+    
+    return false;
 }
 
 bool Program::PerContextProgram::getInfoLog( std::string& infoLog ) const
diff --git a/src/osg/Shader.cpp b/src/osg/Shader.cpp
index 99cf21296..4a7ed4207 100644
--- a/src/osg/Shader.cpp
+++ b/src/osg/Shader.cpp
@@ -201,6 +201,16 @@ const char* Shader::getTypename() const
 }
 
 
+void Shader::releaseGLObjects(osg::State* state) const
+{
+    if (!state) _pcsList.setAllElementsTo(0);
+    else
+    {
+        unsigned int contextID = state->getContextID();
+        _pcsList[contextID] = 0;
+    }
+}
+
 void Shader::compileShader( unsigned int contextID ) const
 {
     PerContextShader* pcs = getPCS( contextID );
diff --git a/src/osgUtil/SceneView.cpp b/src/osgUtil/SceneView.cpp
index cbd75dc76..e863c1922 100644
--- a/src/osgUtil/SceneView.cpp
+++ b/src/osgUtil/SceneView.cpp
@@ -736,6 +736,9 @@ void SceneView::releaseAllGLObjects()
     if (!_camera) return;
    
     _camera->releaseGLObjects(_state.get());
+    
+    // we need to reset State as it keeps handles to Program objects.
+    if (_state.valid()) _state->reset();
 }