-- File:	ShapeAnalysis_TransferPrameters.cdl
-- Created:	Mon Jun 21 09:44:37 1999
-- Author:	Galina KULIKOVA
--		<gka@nnov.matra-dtv.fr>
---Copyright:	 Matra Datavision 1999


class TransferParameters from ShapeAnalysis inherits TShared from MMgt

	---Purpose: This tool is used for transferring parameters
	--          from 3d curve of the edge to pcurve and vice versa.
	--
	--          Default behaviour is to trsnafer parameters with help
	--          of linear transformation:
	--
	--            T2d = myShift + myScale * T3d
	--          where
	--            myScale = ( Last2d - First2d ) / ( Last3d - First3d )
	--            myShift = First2d - First3d * myScale
	--            [First3d, Last3d] and [First2d, Last2d] are ranges of 
        --            edge on curve and pcurve
	--
	--          This behaviour can be redefined in derived classes, for example, 
	--          using projection.

uses
    Edge from TopoDS,
    Face from TopoDS,
    HSequenceOfReal from TColStd,
    HArray1OfReal from TColStd

is
    Create returns mutable TransferParameters from ShapeAnalysis;
    	---Purpose: Creates empty tool with myShift = 0 and myScale = 1
    
    Create(E : Edge from TopoDS; F : Face from TopoDS) 
    returns mutable TransferParameters from ShapeAnalysis;
    	---Purpose: Creates a tool and initializes it with edge and face
    
    Init(me :  mutable;E : Edge from TopoDS; F : Face from TopoDS ) is virtual;
    	---Purpose: Initialize a tool with edge and face
    
    SetMaxTolerance(me:mutable; maxtol: Real);
    	---Purpose: Sets maximal tolerance to use linear recomputation of
	--          parameters.
    
    Perform(me : mutable; Params: HSequenceOfReal from TColStd; To2d : Boolean) 
    returns HSequenceOfReal from TColStd is virtual;
    	---Purpose: Transfers parameters given by sequence Params from 3d curve
	--          to pcurve (if To2d is True) or back (if To2d is False)
     
    Perform(me : mutable;Param : Real; To2d : Boolean) returns Real from Standard is virtual;
    ---Purpose: Transfers parameter given by sequence Params from 3d curve
	--          to pcurve (if To2d is True) or back (if To2d is False)
	
    TransferRange(me: mutable; newEdge : in out Edge from TopoDS; prevPar,currPar : Real;
    	To2d : Boolean) is virtual;
     ---Purpose:Recomputes range of curves from NewEdge.
     --	        If Is2d equals True parameters are recomputed by curve2d else by curve3d.

    IsSameRange (me) returns Boolean is virtual;
    	---Purpose: Returns True if 3d curve of edge and pcurve are SameRange
	--          (in default implementation, if myScale == 1 and myShift == 0)

fields

    myShift       : Real;
    myScale       : Real;
    myFirst       : Real is protected;
    myLast        : Real is protected;
    myFirst2d     : Real;
    myLast2d      : Real;
    myEdge        : Edge from TopoDS is protected;
    myFace        : Face from TopoDS;
    myMaxTolerance: Real is protected;
    
end TransferParameters;