add GetHandle for gfx::Surface

modules/gfx/src/surface.cc

@@ -371,4 +371,9 @@ void Surface::ReapplyColorOps()
   GfxObj::ReapplyColorOps();
 }
 
+ost::mol::SurfaceHandle Surface::GetHandle() const
+{
+  return this->sh_;
+}
+
 }} // ns

modules/gfx/src/surface.hh

@@ -58,6 +58,8 @@ public:
   virtual void CustomRenderPov(PovState& pov);
   virtual geom::AlignedCuboid GetBoundingBox() const;
 
+  mol::SurfaceHandle GetHandle() const;
+
   void Rebuild();
   void Replace(const mol::SurfaceHandle& sh);