Perliminary support for glGenerateMinMapEXT.

src/osg/CameraNode.cpp

@@ -174,11 +174,12 @@ void CameraNode::attach(BufferComponent buffer, GLenum internalFormat)
     _bufferAttachmentMap[buffer]._internalFormat = internalFormat;
 }
 
-void CameraNode::attach(BufferComponent buffer, osg::Texture* texture, unsigned int level, unsigned int face)
+void CameraNode::attach(BufferComponent buffer, osg::Texture* texture, unsigned int level, unsigned int face, bool mipMapGeneration)
 {
     _bufferAttachmentMap[buffer]._texture = texture;
     _bufferAttachmentMap[buffer]._level = level;
     _bufferAttachmentMap[buffer]._face = face;
+    _bufferAttachmentMap[buffer]._mipMapGeneration = mipMapGeneration;
 }
 
 void CameraNode::attach(BufferComponent buffer, osg::Image* image)

src/osgProducer/GraphicsContextImplementation.cpp

@@ -14,6 +14,7 @@
 #include <osgProducer/GraphicsContextImplementation>
 #include <osg/TextureRectangle>
 #include <osg/TextureCubeMap>
+#include <osg/Notify>
 
 using namespace osgProducer;
 
@@ -56,7 +57,8 @@ GraphicsContextImplementation::GraphicsContextImplementation(Traits* traits)
         if (traits->_target)
         {
 
-            _rs->setRenderToTextureOptions(Producer::RenderSurface::RenderToTextureOptions_Default);
+            _rs->setRenderToTextureOptions(traits->_mipMapGeneration ? Producer::RenderSurface::RequestSpaceForMipMaps :
+                                                                       Producer::RenderSurface::RenderToTextureOptions_Default);
             _rs->setRenderToTextureMipMapLevel(traits->_level);
             _rs->setRenderToTextureMode(traits->_alpha>0 ? Producer::RenderSurface::RenderToRGBATexture : 
                                                            Producer::RenderSurface::RenderToRGBTexture);
@@ -70,10 +72,12 @@ GraphicsContextImplementation::GraphicsContextImplementation(Traits* traits)
                     _rs->setRenderToTextureTarget(Producer::RenderSurface::Texture2D);
                     break;
                 case(GL_TEXTURE_3D) :
+                    osg::notify(osg::NOTICE)<<"PBuffer render to Texture3D not supported."<<std::endl;
                     // not supported. 
                     // _rs->setRenderToTextureTarget(Producer::RenderSurface::Texture3D);
                     break;
                 case(GL_TEXTURE_RECTANGLE) : 
+                    osg::notify(osg::NOTICE)<<"PBuffer render to TextureRectangle not supported."<<std::endl;
                     // not supported.
                     // _rs->setRenderToTextureTarget(Producer::RenderSurface::TextureRectangle);
                     break;

src/osgUtil/CullVisitor.cpp

@@ -1066,6 +1066,7 @@ void CullVisitor::apply(osg::CameraNode& camera)
         if (!rtts)
         {
             rtts = new osgUtil::RenderToTextureStage;
+            rtts->setCameraNode(&camera);
             camera.setRenderingCache(rtts.get());
         }
         else

src/osgUtil/RenderToTextureStage.cpp

@@ -43,6 +43,28 @@ 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)
 {
     
@@ -126,6 +148,23 @@ 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())
     {
         // if we have a camera with a post draw callback invoke it.