build 170511. crossroad generation for vbo render path. partial unification of generation and render functions for tracks and ground nodes

renderer.h

@@ -124,6 +124,8 @@ public:
         Render( world_environment *Environment );
     bool
         Render( TGround *Ground );
+    bool
+        Render( TGroundNode *Node );
     bool
         Render( TDynamicObject *Dynamic );
     bool
@@ -134,6 +136,8 @@ public:
         Render( TSubModel *Submodel );
     void
         Render( TMemCell *Memcell );
+    bool
+        Render_Alpha( TGroundNode *Node );
     bool
         Render_Alpha( TDynamicObject *Dynamic );
     bool