From 1f0edca631802471074ebae4cf5d232aaf88a3ec Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Sat, 14 Jul 2007 17:07:59 +0000
Subject: [PATCH] Added support into osg::RenderInfo for a stack of Cameras
 that allow querries of which camera is currently active to be querried from
 within the draw traversal.

---
 include/osg/RenderInfo      | 10 ++++++++++
 include/osgUtil/RenderStage |  2 +-
 src/osgUtil/RenderStage.cpp |  9 ++++++++-
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/include/osg/RenderInfo b/include/osg/RenderInfo
index c8b35bbdf..3ba9a45c2 100644
--- a/include/osg/RenderInfo
+++ b/include/osg/RenderInfo
@@ -30,6 +30,7 @@ public:
     RenderInfo(const RenderInfo& rhs):
         _state(rhs._state),
         _view(rhs._view),
+        _cameras(rhs._cameras),
         _userData(rhs._userData) {}
 
     RenderInfo(State* state, View* view):
@@ -40,6 +41,7 @@ public:
     {
         _state = rhs._state;
         _view = rhs._view;
+        _cameras = rhs._cameras;
         _userData = rhs._userData;
         return *this;
     }
@@ -53,6 +55,11 @@ public:
     void setView(View* view) { _view = view; }
     View* getView() { return _view.get(); }
     const View* getView() const { return _view.get(); }
+    
+    void pushCamera(Camera* camera) { _cameras.push_back(camera); }    
+    void popCamera() { if (_cameras.empty()) _cameras.pop_back(); }
+    
+    Camera* getCurrentCamera() { return _cameras.empty() ? 0 : _cameras.back(); }
 
     void setUserData(Referenced* userData) { _userData = userData; }
     Referenced* getUserData() { return _userData.get(); }
@@ -60,8 +67,11 @@ public:
 
 protected:
 
+    typedef std::vector<Camera*> Cameras;
+
     ref_ptr<State>          _state;
     observer_ptr<View>      _view;
+    Cameras                 _cameras;
     ref_ptr<Referenced>     _userData;
 };
 
diff --git a/include/osgUtil/RenderStage b/include/osgUtil/RenderStage
index 6716b574e..a0c772f5e 100644
--- a/include/osgUtil/RenderStage
+++ b/include/osgUtil/RenderStage
@@ -236,7 +236,7 @@ class OSGUTIL_EXPORT RenderStage : public RenderBin
         double                              _clearDepth;
         int                                 _clearStencil;
 
-        bool                                    _cameraRequiresSetUp;
+        bool                                _cameraRequiresSetUp;
         osg::Camera*                        _camera;
         
         osg::ref_ptr<osg::Texture>              _texture;
diff --git a/src/osgUtil/RenderStage.cpp b/src/osgUtil/RenderStage.cpp
index 0054348b3..b3b6c7705 100644
--- a/src/osgUtil/RenderStage.cpp
+++ b/src/osgUtil/RenderStage.cpp
@@ -988,7 +988,10 @@ void RenderStage::drawImplementation(osg::RenderInfo& renderInfo,RenderLeaf*& pr
         notify(FATAL) << "Error: cannot draw stage due to undefined viewport."<< std::endl;
         return;
     }
-     
+
+    // push the stages camera so that drawing code can querry it     
+    if (_camera) renderInfo.pushCamera(_camera);
+
     // set up the back buffer.
     state.applyAttribute(_viewport.get());
 
@@ -1048,6 +1051,10 @@ void RenderStage::drawImplementation(osg::RenderInfo& renderInfo,RenderLeaf*& pr
     RenderBin::drawImplementation(renderInfo,previous);
 
     state.apply();
+
+    // pop the render stages camera.
+    if (_camera) renderInfo.popCamera();
+
 }
 
 void RenderStage::drawPostRenderStages(osg::RenderInfo& renderInfo,RenderLeaf*& previous)