Further work on trying to get glGenerateMipMapEXT working in conjunction with

frame buffer objects.  Still don't work under Linux yet through :-|

src/osg/FrameBufferObject.cpp

@@ -272,7 +272,7 @@ FrameBufferAttachment &FrameBufferAttachment::operator = (const FrameBufferAttac
     return *this;
 }
 
-void FrameBufferAttachment::attach(State &state, GLenum attachment_point, const FBOExtensions* ext) const
+void FrameBufferAttachment::createRequiredTexturesAndApplyGenerateMipMap(State &state, const FBOExtensions* ext) const
 {
     unsigned int contextID = state.getContextID();
 
@@ -285,11 +285,41 @@ void FrameBufferAttachment::attach(State &state, GLenum attachment_point, const
         {
             _ximpl->textureTarget->compileGLObjects(state);
             tobj = _ximpl->textureTarget->getTextureObject(contextID);
+
+        }
+        if (!tobj || tobj->_id == 0)
+            return;
+
+        Texture::FilterMode minFilter = _ximpl->textureTarget->getFilter(Texture::MIN_FILTER);
+        if (minFilter==Texture::LINEAR_MIPMAP_LINEAR || 
+            minFilter==Texture::LINEAR_MIPMAP_NEAREST || 
+            minFilter==Texture::NEAREST_MIPMAP_LINEAR || 
+            minFilter==Texture::NEAREST_MIPMAP_NEAREST)
+        {
+            ext->glGenerateMipmapEXT(_ximpl->textureTarget->getTextureTarget());
+        }
+
+    }
+}
+
+void FrameBufferAttachment::attach(State &state, GLenum attachment_point, const FBOExtensions* ext) const
+{
+    unsigned int contextID = state.getContextID();
+
+    Texture::TextureObject *tobj = 0;
+    if (_ximpl->textureTarget.valid())
+    {
+        tobj = _ximpl->textureTarget->getTextureObject(contextID);
+        if (!tobj || tobj->_id == 0)
+        {
+            _ximpl->textureTarget->compileGLObjects(state);
+            tobj = _ximpl->textureTarget->getTextureObject(contextID);
+
         }
         if (!tobj || tobj->_id == 0)
             return;
     }
-
+    
     switch (_ximpl->targetType)
     {
     default:
@@ -379,9 +409,22 @@ void FrameBufferObject::apply(State &state) const
             notify(WARN) << "Warning: FrameBufferObject: could not create the FBO" << std::endl;
             return;
         }
+
         dirtyAttachmentList = 1;
+
     }
 
+    if (dirtyAttachmentList)
+    {
+        // create textures and mipmaps before we bind the frame buffer object
+        for (AttachmentMap::const_iterator i=_attachments.begin(); i!=_attachments.end(); ++i)
+        {
+            const FrameBufferAttachment &fa = i->second;
+            fa.createRequiredTexturesAndApplyGenerateMipMap(state, ext);
+        }
+
+    }
+    
     ext->glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fboID);
 
     if (dirtyAttachmentList)

src/osgUtil/RenderToTextureStage.cpp

@@ -16,6 +16,7 @@
 #include <osg/Texture3D>
 #include <osg/TextureRectangle>
 #include <osg/TextureCubeMap>
+#include <osg/Notify>
 
 using namespace osg;
 using namespace osgUtil;
@@ -43,35 +44,12 @@ void RenderToTextureStage::reset()
     RenderStage::reset();
 }
 
-class GenerateMipMapHelper : public StateAttribute::ModeUsage
-{
-    public:
-        GenerateMipMapHelper(osg::FBOExtensions* fbo_ext):
-            _fbo_ext(fbo_ext) {}
-            
-        virtual ~GenerateMipMapHelper() {}
-        
-        virtual void usesMode(StateAttribute::GLMode)
-        {
-        }
-
-        virtual void usesTextureMode(StateAttribute::GLMode mode)
-        {
-            _fbo_ext->glGenerateMipmapEXT((GLenum)mode);
-        }
-        
-        osg::FBOExtensions* _fbo_ext;
-        
-};
-
 
 void RenderToTextureStage::draw(osg::State& state,RenderLeaf*& previous)
 {
     
     if (_stageDrawnThisFrame) return;
 
-    state.checkGLErrors("beginning of RenderToTextureStage::draw()");
-
     //cout << "begining RTTS draw "<<this<< "  "<<_viewport->x()<<","<< _viewport->y()<<","<< _viewport->width()<<","<< _viewport->height()<<std::endl;
     
     osg::State* useState = &state;
@@ -148,22 +126,6 @@ void RenderToTextureStage::draw(osg::State& state,RenderLeaf*& previous)
         _image->readPixels(_viewport->x(),_viewport->y(),_viewport->width(),_viewport->height(),_imageReadPixelFormat,_imageReadPixelDataType);
     }
        
-    if (fbo_supported && _camera)
-    {
-        // now generate mipmaps if they are required.
-        const osg::CameraNode::BufferAttachmentMap& bufferAttachements = _camera->getBufferAttachmentMap();
-        for(osg::CameraNode::BufferAttachmentMap::const_iterator itr = bufferAttachements.begin();
-            itr != bufferAttachements.end();
-            ++itr)
-        {
-            if (itr->second._texture.valid() && itr->second._mipMapGeneration) 
-            {
-                itr->second._texture->apply(*useState);
-                GenerateMipMapHelper generateMipMap(fbo_ext);
-                itr->second._texture->getModeUsage(generateMipMap);
-            }
-        }
-    }
     
     if (_camera && _camera->getPostDrawCallback())
     {
@@ -176,6 +138,22 @@ void RenderToTextureStage::draw(osg::State& state,RenderLeaf*& previous)
         // switch of the frame buffer object
         fbo_ext->glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
     }
+    
+    if (fbo_supported && _camera)
+    {
+        // now generate mipmaps if they are required.
+        const osg::CameraNode::BufferAttachmentMap& bufferAttachements = _camera->getBufferAttachmentMap();
+        for(osg::CameraNode::BufferAttachmentMap::const_iterator itr = bufferAttachements.begin();
+            itr != bufferAttachements.end();
+            ++itr)
+        {
+            if (itr->second._texture.valid() && itr->second._mipMapGeneration) 
+            {
+                itr->second._texture->apply(*useState);
+                // fbo_ext->glGenerateMipmapEXT(itr->second._texture->getTextureTarget());
+            }
+        }
+    }
 
     if (callingContext && useContext != callingContext)
     {
@@ -184,8 +162,5 @@ void RenderToTextureStage::draw(osg::State& state,RenderLeaf*& previous)
 
         glReadBuffer(GL_BACK);
     }
-    
-    state.checkGLErrors("end of RenderToTextureStage::draw()");
-    
 }