-- File:	GccEnt.cdl
-- Created:	Tue Mar  5 12:06:03 1991
-- Author:	Remy GILET
--		<reg@topsn3>
---Copyright:	 Matra Datavision 1991

package GccEnt

    ---Purpose: This package provides an implementation of the qualified
    --          entities useful to create 2d entities with geometric 
    --          constraints. The qualifier explains which subfamily of
    --          solutions we want to obtain. It uses the following law: the
    --          matter/the interior side is at the left of the line, if we go
    --          from the beginning to the end.
    --          The qualifiers are:
    --            Enclosing   : the solution(s) must enclose the argument.
    --            Enclosed    : the solution(s) must be enclosed in the
    --                          argument.
    --            Outside     : both the solution(s) and the argument must be
    --                          outside to each other.
    --            Unqualified : the position is undefined, so give all the
    --                          solutions.
    --          The use of a qualifier is always required if such 
    --          subfamilies exist. For example, it is not used for a point.
    -- Note:    the interior of a curve is defined as the left-hand
    --          side of the curve in relation to its orientation.
uses gp,
     Standard,
     TCollection

is

    --- Level : Public  
    --  All methods of all  classes will be public.


    -- General deferred classes of geometric qualifiers:

    exception BadQualifier inherits DomainError from Standard;

    class QualifiedLin;

    class QualifiedCirc;

    generic class QualifiedCurv;

    enumeration Position is 
    	unqualified, enclosing, enclosed, outside, noqualifier;
    	---Purpose:
    	-- Qualifies the position of a solution of a construction
    	-- algorithm with respect to one of its arguments. This is one of the following:
    	-- -   GccEnt_unqualified: the position of the solution
    	--   is undefined with respect to the argument,
    	-- -   GccEnt_enclosing: the solution encompasses the argument,
    	-- -   GccEnt_enclosed: the solution is encompassed by the argument,
    	-- -   GccEnt_outside: the solution and the argument
    	--   are external to one another,
    	-- -   GccEnt_noqualifier: the value returned during a
    	--   consultation of the qualifier when the argument is
    	--   defined as GccEnt_unqualified.
    	-- Note: the interior of a line or any open curve is
    	-- defined as the left-hand side of the line or curve in
    	-- relation to its orientation.
        
    class Array1OfPosition instantiates 
    	Array1 from TCollection (Position from GccEnt);

    Unqualified(Obj : Lin2d from gp) returns QualifiedLin;
    	---Purpose: Constructs a qualified line,
    	-- so that the relative position to the circle or line of the
    	-- solution computed by a construction algorithm using the
    	-- qualified circle or line is not qualified, i.e. all solutions apply.
    Unqualified(Obj : Circ2d from gp) returns QualifiedCirc;
    	---Purpose: Constructs a qualified circle
    	-- so that the relative position to the circle or line of the
    	-- solution computed by a construction algorithm using the
    	-- qualified circle or line is not qualified, i.e. all solutions apply.


    Enclosing(Obj : Circ2d from gp) returns QualifiedCirc;
    	---Purpose:
    	-- Constructs such a qualified circle that the solution
    	-- computed by a construction algorithm using the qualified
    	-- circle encloses the circle.


    Enclosed(Obj : Lin2d from gp) returns QualifiedLin;
    	---Purpose: Constructs a qualified line,
    	-- so that the solution computed by a construction
    	-- algorithm using the qualified circle or line is enclosed by
    	-- the circle or line.
    Enclosed(Obj : Circ2d from gp) returns QualifiedCirc;
    	---Purpose: Constructs a qualified circle
    	-- so that the solution computed by a construction
    	-- algorithm using the qualified circle or line is enclosed by
    	-- the circle or line.


    Outside(Obj : Lin2d from gp) returns QualifiedLin;
    	---Purpose: Constructs a qualified line,
    	-- so that the solution computed by a construction
    	-- algorithm using the qualified circle or line and the circle
    	-- or line are external to one another.
    Outside(Obj : Circ2d from gp) returns QualifiedCirc;
    	---Purpose: Constructs a qualified circle
    	-- so that the solution computed by a construction
    	-- algorithm using the qualified circle or line and the circle
    	-- or line are external to one another.

end GccEnt;