Add some comments, see #43

--HG--
branch : multipass-stereo

code/nel/include/nel/3d/stereo_ovr.h

@@ -99,18 +99,25 @@ public:
 	/// Gets the current camera matrix
 	virtual void getCurrentMatrix(NL3D::UCamera *camera) const;
 
+	/// At the start of a new render target
 	virtual bool beginClear();
+	// virtual void *getRenderTarget() const;
 	virtual void endClear();
 	
+	/// The 3D scene
 	virtual bool beginScene();
 	virtual void endScene();
 
+	/// Interface within the 3D scene
 	virtual bool beginInterface3D();
 	virtual void endInterface3D();
 	
+	/// 2D Interface
 	virtual bool beginInterface2D();
 	virtual void endInterface2D();
 
+
+	/// Get the HMD orientation
 	virtual NLMISC::CQuat getOrientation() const;