-- Created on: 1997-02-12
-- Created by: Alexander BRIVIN
-- Copyright (c) 1997-1999 Matra Datavision
-- Copyright (c) 1999-2014 OPEN CASCADE SAS
--
-- This file is part of Open CASCADE Technology software library.
--
-- This library is free software; you can redistribute it and / or modify it
-- under the terms of the GNU Lesser General Public version 2.1 as published
-- by the Free Software Foundation, with special exception defined in the file
-- OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
-- distribution for complete text of the license and disclaimer of any warranty.
--
-- Alternatively, this file may be used under the terms of Open CASCADE
-- commercial license or contractual agreement.

class PerspectiveCamera from Vrml 

	---Purpose: specifies a PerspectiveCamera node of VRML specifying properties of cameras. 
    	--  A perspective camera defines a perspective projection from a viewpoint. The viewing
       	--  volume for a perspective camera is a truncated right pyramid. 
uses
 
     Vec         from gp, 
     SFRotation  from  Vrml
is
                                                    --  defaults  :
    Create  returns  PerspectiveCamera from Vrml;   --  myPosition(0 0 1) Camera looks along the negative Z-axis
 						    --  myOrientation(0 0 1 0)
						    --  myFocalDistance(5)
						    --  myHeightAngle(0.785398)
    Create  ( aPosition      :  Vec         from  gp; 
    	      aOrientation   :  SFRotation  from  Vrml; 
    	      aFocalDistance :  Real        from  Standard; 
    	      aHeightAngle   :  Real        from  Standard ) 
    	returns  PerspectiveCamera from Vrml; 

    SetPosition ( me : in out;  aPosition : Vec  from  gp );
    Position ( me  )  returns Vec  from  gp;

    SetOrientation ( me : in out;  aOrientation : SFRotation  from  Vrml );
    Orientation ( me )  returns SFRotation  from  Vrml;

    SetFocalDistance ( me : in out;  aFocalDistance : Real  from  Standard );
    FocalDistance ( me )  returns Real  from  Standard;

    SetAngle ( me : in out;  aHeightAngle : Real  from  Standard );
    Angle ( me )  returns  Real  from  Standard;

    Print  ( me;  anOStream: in out OStream from Standard) returns OStream from Standard;
    ---C++:  return  & 

fields
 
    myPosition      :  Vec         from  gp;       -- Location of viewpoint
    myOrientation   :  SFRotation  from  Vrml;     -- Orientation (rotation with respect to (0,0,-1) vector)     
    myFocalDistance :  Real        from  Standard; -- Distance from viewpoint to point of focus.
    myHeightAngle   :  Real        from  Standard; -- Angle (in radians) of field
    	    	    	    	    	    	   -- of  view, in  height  direction
end PerspectiveCamera;