-- File:	Geom_Line.cdl
-- Created:	Wed Mar 10 09:46:21 1993
-- Author:	Philippe DAUTRY
--		<fid@phylox>
-- Copyright:	 Matra Datavision 1993


class Line from Geom inherits Curve from Geom


        ---Purpose : Describes an infinite line.
    	-- A line is defined and positioned in space with an axis
    	-- (gp_Ax1 object) which gives it an origin and a unit vector.
    	-- The Geom_Line line is parameterized:
    	-- P (U) = O + U*Dir, where:
    	-- - P is the point of parameter U,
    	-- - O is the origin and Dir the unit vector of its positioning axis.
    	--   The parameter range is ] -infinite, +infinite [.
    	-- The orientation of the line is given by the unit vector
    	-- of its positioning axis.
      

uses Ax1      from gp,
     Ax2      from gp, 
     Dir      from gp, 
     Lin      from gp, 
     Pnt      from gp, 
     Vec      from gp,
     Trsf     from gp,
     Geometry from Geom,
     Shape   from GeomAbs


raises RangeError  from Standard

is



  Create (A1 : Ax1)   returns mutable Line;
        ---Purpose :
        --  Creates a line located in 3D space with the axis placement A1.
        --  The Location of A1 is the origin of the line. 


  Create (L : Lin)  returns mutable Line;
        ---Purpose :
        --  Creates a line from a non transient line from package gp.


  Create (P : Pnt; V : Dir)    returns mutable Line;
        ---Purpose :
    	-- Constructs a line passing through point P and parallel to vector V
    	--   (P and V are, respectively, the origin and the unit
    	--   vector of the positioning axis of the line). 


  SetLin (me : mutable; L : Lin)
        ---Purpose :
        --  Set <me> so that <me> has the same geometric properties as L.
  is static;

  SetDirection (me : mutable; V : Dir)
        ---Purpose : changes the direction of the line.
  is static;


  SetLocation (me : mutable; P : Pnt)
        ---Purpose : 
        --  changes the "Location" point (origin) of the line.
  is static;


  SetPosition (me : mutable; A1 : Ax1)
        ---Purpose :
        --  changes the "Location" and a the "Direction" of <me>.
  is static;


  Lin (me)  returns Lin from gp
        ---Purpose : 
        --  Returns non transient line from gp with the same geometric
        --  properties as <me>
  is static;

  Position(me) returns Ax1 from gp
       	---C++: return const &
       	---Purpose: Returns the positioning axis of this line; this is also its local coordinate system.
  is static;

  Reverse (me : mutable);
        ---Purpose : Changes the orientation of this line. As a result, the
    	-- unit vector of the positioning axis of this line is reversed.


  ReversedParameter(me; U : Real) returns Real;
	---Purpose: Computes the parameter on the reversed line for the
    	-- point of parameter U on this line.
    	-- For a line, the returned value is -U.


  FirstParameter (me)  returns Real;
        ---Purpose : Returns the value of the first parameter of this
    	-- line. This is Standard_Real::RealFirst().


  LastParameter (me)   returns Real;
        ---Purpose : Returns the value of the last parameter of this
    	-- line. This is  Standard_Real::RealLast().



  IsClosed (me)  returns Boolean;
        ---Purpose : returns False


  IsPeriodic (me)   returns Boolean;
        ---Purpose : returns False


  Continuity (me)   returns Shape from GeomAbs;
        ---Purpose : Returns GeomAbs_CN, which is the global continuity of any line.
        
  IsCN (me; N : Integer) returns Boolean
        ---Purpose: returns True.
    raises RangeError;
       	---Purpose: Raised if N < 0.

  D0(me; U : Real; P : out Pnt);
	---Purpose: Returns in P the point of parameter U.
       	--  P (U) = O + U * Dir where O is the "Location" point of the 
       	--  line and Dir the direction of the line.

  D1 (me; U : Real; P : out Pnt; V1 : out Vec);
        ---Purpose :
        --  Returns the point P of parameter u and the first derivative V1.


  D2 (me; U : Real; P : out Pnt; V1, V2 : out Vec);
        ---Purpose :
        --  Returns the point P of parameter U, the first and second 
        --  derivatives V1 and V2. V2 is a vector with null magnitude
        --  for a line.


  D3 (me; U : Real; P : out Pnt; V1, V2, V3 : out Vec);
        ---Purpose :
        --  V2 and V3 are vectors with null magnitude for a line.

        
  DN (me; U : Real; N : Integer)   returns Vec
        ---Purpose :
        --  The returned vector gives the value of the derivative for the 
        --  order of derivation N.
     raises RangeError;
        ---Purpose : Raised if N < 1.





  Transform (me : mutable; T : Trsf);
    	---Purpose: Applies the transformation T to this line.
    
  TransformedParameter(me; U : Real; T : Trsf from gp) returns Real
	---Purpose: Returns the  parameter on the  transformed  curve for
	--          the transform of the point of parameter U on <me>.
	--          
	--          me->Transformed(T)->Value(me->TransformedParameter(U,T))
	--          
	--          is the same point as
	--          
	--          me->Value(U).Transformed(T)
	--          
	--          This methods returns <U> * T.ScaleFactor()
     is redefined;  

  ParametricTransformation(me; T : Trsf from gp) returns Real
	---Purpose: Returns a  coefficient to compute the parameter on
	--          the transformed  curve  for  the transform  of the
	--          point on <me>.
	--          
	--          Transformed(T)->Value(U * ParametricTransformation(T))
	--          
	--          is the same point as
	--          
	--          Value(U).Transformed(T)
	--          
	--          This methods returns T.ScaleFactor()
     is redefined;  


  Copy (me)  returns mutable like me;
    	---Purpose: Creates a new object which is a copy of this line.


fields

  pos : Ax1;

end;