1. package GLOBE_3D.Portals is 
  2.  
  3.   -- Methods provided for clipping through screen rectangles 
  4.  
  5.   procedure Intersect (A, B : Rectangle; C : out Rectangle; non_empty : out Boolean); 
  6.  
  7.   procedure Find_bounding_box ( 
  8.     o       :     Object_3D'Class; 
  9.     face    :     Positive; 
  10.     b       : out Rectangle; 
  11.     success : out Boolean 
  12. ); 
  13.  
  14.   procedure Draw_boundary (main, clip : Rectangle); 
  15.  
  16. end GLOBE_3D.Portals;