[FIX #316] Moved viewport query to viewer's camera which is used as reference...

[FIX #316] Moved viewport query to viewer's camera which is used as reference in the image overlay effect. This is quite ugly but OSG requires us to do this.

src/core/graphicsEngine/WGEViewer.cpp

@@ -179,6 +179,8 @@ osg::ref_ptr<osg::Camera> WGEViewer::getCamera()
 
 void WGEViewer::setScene( osg::ref_ptr< WGEGroupNode > node )
 {
+    m_effectImageOverlay->setReferenceViewer( shared_from_this() );
+
     m_View->setSceneData( node );
     m_scene = node;
 

src/core/graphicsEngine/WGEViewerEffectImageOverlay.cpp

@@ -31,6 +31,8 @@
 #include "../common/WProperties.h"
 #include "../common/WLogger.h"
 
+#include "WGEViewer.h"
+
 #include "callbacks/WGEFunctorCallback.h"
 #include "shaders/WGEShader.h"
 #include "shaders/WGEPropertyUniform.h"
@@ -40,7 +42,7 @@
 WGEViewerEffectImageOverlay::WGEViewerEffectImageOverlay():
     WGEViewerEffect( "Image Overlay", "Blend in some arbitrary image." )
 {
-    WPropFilename imageFn = m_properties->addProperty( "Image", "The Image to use.", WPathHelper::getSharePath() / "GE" / "overlay.png" );
+    m_image = m_properties->addProperty( "Image", "The Image to use.", WPathHelper::getSharePath() / "GE" / "overlay.png" );
     WPropDouble scale = m_properties->addProperty( "Scale", "Scale the image in percent.", 50.0 );
     scale->setMin( 0.0 );
     scale->setMax( 200.0 );
@@ -51,49 +53,36 @@ WGEViewerEffectImageOverlay::WGEViewerEffectImageOverlay():
     osg::ref_ptr< WGEShader > overlayShader = new WGEShader( "WGECameraOverlayTexture" );
     overlayShader->apply( m_geode );
 
-    // some logo
-    osg::ref_ptr< osg::Texture2D > logoTexture = new osg::Texture2D;
-    osg::Image* logoImage = osgDB::readImageFile( imageFn->get().string() );
-    if( logoImage )
-    {
-        // Assign the texture to the image we read from file:
-        logoTexture->setImage( logoImage );
-
-        // no wrapping
-        logoTexture->setWrap( osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_BORDER );
-        logoTexture->setWrap( osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_BORDER );
-        logoTexture->setDataVariance( osg::Object::DYNAMIC );
-
-        // texture width and height
-        m_overlayWidth = new osg::Uniform( "u_overlayWidth", static_cast< float >( logoImage->s() ) );
-        m_overlayHeight = new osg::Uniform( "u_overlayHeight", static_cast< float >( logoImage->t() ) );
-        m_state->addUniform( m_overlayWidth );
-        m_state->addUniform( m_overlayHeight );
-
-        // NOTE: the values of these uniforms get updated by the updateViewport callback, so these values are only placeholders
-        m_viewportWidth = new osg::Uniform( "u_viewportWidth", static_cast< float >( 1024 ) );
-        m_viewportHeight = new osg::Uniform( "u_viewportHeight", static_cast< float >( 768 ) );
-        m_state->addUniform( m_viewportWidth );
-        m_state->addUniform( m_viewportHeight );
-
-        m_state->addUniform( new WGEPropertyUniform< WPropDouble >( "u_overlayScalePerc", scale ) );
-        m_state->addUniform( new WGEPropertyUniform< WPropBool >( "u_toTop", moveToTop ) );
-        m_state->addUniform( new WGEPropertyUniform< WPropBool >( "u_toRight", moveToRight ) );
-
-        // add a callback which handles changes in viewport size
-        osg::ref_ptr< ViewportUpdater > viewportUpd( new ViewportUpdater() );
-        viewportUpd->m_viewportWidth = m_viewportWidth;
-        viewportUpd->m_viewportHeight = m_viewportHeight;
-        setPreDrawCallback( viewportUpd );
-
-        // bind
-        m_state->setTextureAttributeAndModes( 0, logoTexture, osg::StateAttribute::ON );
-    }
-    else
-    {
-        wlog::error( "WGECameraEffect" ) << "Could not load overlay image \"" <<
-                                            ( WPathHelper::getSharePath() / "GE" / "overlay.png" ).string()  << "\".";
-    }
+    m_forceReload = true;
+
+    // texture setup, Loading is done later in the update callback.
+    m_logoTexture = new osg::Texture2D;
+    m_logoTexture->setDataVariance( osg::Object::DYNAMIC );
+    // no wrapping
+    m_logoTexture->setWrap( osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_BORDER );
+    m_logoTexture->setWrap( osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_BORDER );
+
+    // texture width and height (gets set by the update callback)
+    m_overlayWidth = new osg::Uniform( "u_overlayWidth", static_cast< float >( 1 ) );
+    m_overlayHeight = new osg::Uniform( "u_overlayHeight", static_cast< float >( 1 ) );
+    m_state->addUniform( m_overlayWidth );
+    m_state->addUniform( m_overlayHeight );
+    // NOTE: the values of these uniforms get updated by the updateViewport callback, so these values are only placeholders
+    m_viewportWidth = new osg::Uniform( "u_viewportWidth", static_cast< float >( 1024 ) );
+    m_viewportHeight = new osg::Uniform( "u_viewportHeight", static_cast< float >( 768 ) );
+    m_state->addUniform( m_viewportWidth );
+    m_state->addUniform( m_viewportHeight );
+
+    m_state->addUniform( new WGEPropertyUniform< WPropDouble >( "u_overlayScalePerc", scale ) );
+    m_state->addUniform( new WGEPropertyUniform< WPropBool >( "u_toTop", moveToTop ) );
+    m_state->addUniform( new WGEPropertyUniform< WPropBool >( "u_toRight", moveToRight ) );
+
+    // add a callback which handles changes in viewport size
+    m_updater = new Updater();
+    addUpdateCallback( m_updater );
+
+    // bind
+    m_state->setTextureAttributeAndModes( 0, m_logoTexture, osg::StateAttribute::ON );
 }
 
 WGEViewerEffectImageOverlay::~WGEViewerEffectImageOverlay()
@@ -101,3 +90,53 @@ WGEViewerEffectImageOverlay::~WGEViewerEffectImageOverlay()
     // cleanup
 }
 
+void WGEViewerEffectImageOverlay::setReferenceViewer( WGEViewer::SPtr viewer )
+{
+    m_viewer = viewer;
+}
+
+const boost::shared_ptr< WGEViewer > WGEViewerEffectImageOverlay::getReferenceViewer() const
+{
+    return m_viewer;
+}
+
+void WGEViewerEffectImageOverlay::Updater::operator() ( osg::Node* node, osg::NodeVisitor* nv )
+{
+    WGEViewerEffectImageOverlay* effect = dynamic_cast< WGEViewerEffectImageOverlay* >( node );
+    if( effect )
+    {
+        // viewer set?
+        if( effect->m_viewer )
+        {
+            // valid camera? -> update viewport
+            osg::Camera* cam = effect->m_viewer->getCamera();
+            if( cam )
+            {
+                // valid viewport?
+                if( cam->getViewport() )
+                {
+                    effect->m_viewportWidth->set( static_cast< float >( cam->getViewport()->width() ) );
+                    effect->m_viewportHeight->set( static_cast< float >( cam->getViewport()->height() ) );
+                }
+            }
+
+            // update image if needed
+            if( effect->m_forceReload || effect->m_image->changed() )
+            {
+                effect->m_forceReload = false;
+                osg::Image* logoImage = osgDB::readImageFile( effect->m_image->get( true ).string() );
+                if( logoImage )
+                {
+                    effect->m_logoTexture->setImage( logoImage );
+                    effect->m_overlayWidth->set( static_cast< float >( logoImage->s() ) );
+                    effect->m_overlayHeight->set( static_cast< float >( logoImage->t() ) );
+                }
+            }
+        }
+    }
+
+    // call nested callbacks
+    traverse( node, nv );
+    return;
+}
+

src/core/graphicsEngine/WGEViewerEffectImageOverlay.h

@@ -25,8 +25,12 @@
 #ifndef WGEVIEWEREFFECTIMAGEOVERLAY_H
 #define WGEVIEWEREFFECTIMAGEOVERLAY_H
 
+#include "core/common/WLogger.h"
+
 #include "WGEViewerEffect.h"
 
+class WGEViewer;
+
 /**
  * Image Overlay Effect.
  */
@@ -53,6 +57,21 @@ public:
      */
     virtual ~WGEViewerEffectImageOverlay();
 
+    /**
+     * Set the reference viewer. Needed as the effect itself is not able to query important camera states. This can be the viewer on which the
+     * effect is applied but does not have to. Important is a valid osg::Camera, including a properly setup viewport.
+     *
+     * \param viewer the viewer in which the effect is used.
+     */
+    void setReferenceViewer( boost::shared_ptr< WGEViewer > viewer );
+
+    /**
+     * Query current reference viewer.
+     *
+     * \return the reference viewer or NULL if none has been set.
+     */
+    const boost::shared_ptr< WGEViewer > getReferenceViewer() const;
+
 protected:
     /**
      * Width of the image in pixels.
@@ -74,34 +93,45 @@ protected:
      */
     osg::ref_ptr< osg::Uniform > m_viewportHeight;
 
+    /**
+     * The viewer used to query the current reference cam.
+     */
+    boost::shared_ptr< WGEViewer > m_viewer;
+
+    /**
+     * The filename to load.
+     */
+    WPropFilename m_image;
+
+    /**
+     * The texture.
+     */
+    osg::ref_ptr< osg::Texture2D > m_logoTexture;
+
+    /**
+     * If true, the update callback is forced to reload the image.
+     */
+    bool m_forceReload;
+
 private:
     /**
-     * Update the viewport uniforms
+     * Update the uniforms and textures if needed
      */
-    class ViewportUpdater: public osg::Camera::DrawCallback
+    class Updater: public osg::NodeCallback
     {
     public:
         /**
-         * Called before draw.
+         * Called before draw on update
          *
-         * \param renderInfo current render state
+         * \param node the node
+         * \param nv the visitor calling this.
          */
-        virtual void operator() ( osg::RenderInfo& renderInfo ) const   // NOLINT: non const ref
-        {
-            m_viewportWidth->set( static_cast< float >( renderInfo.getState()->getCurrentViewport()->width() ) );
-            m_viewportHeight->set( static_cast< float >( renderInfo.getState()->getCurrentViewport()->height() ) );
-        }
-
-        /**
-        * Width of the viewport in pixels.
-        */
-        osg::ref_ptr< osg::Uniform > m_viewportWidth;
-
-        /**
-         * Height of the viewport in pixels.
-        */
-        osg::ref_ptr< osg::Uniform > m_viewportHeight;
+        virtual void operator() ( osg::Node* node, osg::NodeVisitor* nv );
     };
+    /**
+     * Update callback for the viewport.
+     */
+    osg::ref_ptr< Updater > m_updater;
 };
 
 #endif  // WGEVIEWEREFFECTIMAGEOVERLAY_H