Merged from svn/trunk : "Fixed handling of case where the

          master and the slave camera are placed on the same
          GraphisContext, or when the master camera and slave camera are
          assigned to different Camers. Note normally one doesn't mix
          master with GraphicsContexts and slave cameras so neither case is
          common."

src/osg/GraphicsContext.cpp

@@ -819,6 +819,7 @@ void GraphicsContext::resizedImplementation(int x, int y, int width, int height)
             osg::View* view = camera->getView();
             osg::View::Slave* slave = view ? view->findSlaveForCamera(camera) : 0;
 
+
             if (slave)
             {
                 if (camera->getReferenceFrame()==osg::Transform::RELATIVE_RF)
@@ -849,6 +850,29 @@ void GraphicsContext::resizedImplementation(int x, int y, int width, int height)
                     case(osg::Camera::VERTICAL): camera->getProjectionMatrix() *= osg::Matrix::scale(1.0, aspectRatioChange,1.0); break;
                     default: break;
                 }
+
+                osg::Camera* master = view ? view->getCamera() : 0;
+                if (view && camera==master)
+                {
+                    for(unsigned int i=0; i<view->getNumSlaves(); ++i)
+                    {
+                        osg::View::Slave& child = view->getSlave(i);
+                        if (child._camera.valid() && child._camera->getReferenceFrame()==osg::Transform::RELATIVE_RF)
+                        {
+                            // scale the slaves by the inverse of the change that has been applied to master, to avoid them be
+                            // scaled twice (such as when both master and slave are on the same GraphicsContexts) or by the wrong scale
+                            // when master and slave are on different GraphicsContexts.
+                            switch(policy)
+                            {
+                                case(osg::Camera::HORIZONTAL): child._projectionOffset *= osg::Matrix::scale(aspectRatioChange,1.0,1.0); break;
+                                case(osg::Camera::VERTICAL): child._projectionOffset *= osg::Matrix::scale(1.0, 1.0/aspectRatioChange,1.0); break;
+                                default: break;
+                            }
+                        }
+                    }
+                }
+
+
             }
 
         }