-- File:	AIS_RadiusDimension.cdl
-- Created:	Tue Dec  3 17:56:20 1996
-- Author:	Jean-Pierre COMBE/Odile Olivier
--		<odl@sacadox.paris1.matra-dtv.fr> 
--              modified by  <SZY>  feb-20-98
---Copyright:	 Matra Datavision 1996


class RadiusDimension from AIS inherits Relation from AIS

	---Purpose:  A framework to define display of radii.
    	-- These displays serve as relational references in 3D
    	-- presentations of surfaces, and are particularly useful
    	-- in viewing fillets. The display consists of arrows and
    	-- text giving the length of a radius. This display is
    	-- recalculated if the applicative owner shape changes
    	-- in dimension, and the text gives the modified length.
    	-- The algorithm analyzes a length along a face as an
    	-- arc. It then reconstructs the circle corresponding to
    	-- the arc and calculates the radius of this circle.

uses Shape                 from TopoDS,
     Presentation          from Prs3d,
     PresentationManager3d from PrsMgr,
     Selection             from SelectMgr,
     Pnt                   from gp, 
     Lin                   from gp,
     Circ                  from gp,
     Projector             from Prs3d,
    Transformation        from Geom,
     PresentationManager2d from PrsMgr,
     GraphicObject         from Graphic2d,    
     ExtendedString        from TCollection,
     ArrowSide             from DsgPrs,
     KindOfDimension       from AIS      

is
    Create (aShape      : Shape          from TopoDS;
	    aVal        : Real           from Standard;
	    aText       : ExtendedString from TCollection)         
    	---Purpose: Constructs the radius display object defined by the
    	-- shape aShape, the dimension aVal, and the text aText.
	    
    returns mutable RadiusDimension from AIS;
 
    Create (aShape      : Shape          from TopoDS;
	    aVal        : Real           from Standard;
	    aText       : ExtendedString from TCollection;         
	    aPosition   : Pnt            from gp;
	    aSymbolPrs  : ArrowSide      from DsgPrs;    
    	    anArrowSize : Real           from Standard = 0.0) 
    	---Purpose: Constructs radius display object defined by the shape
    	-- aShape, the dimension aVal, the position aPosition,
    	-- the type of arrow aSymbolPrs, the arrow length
    	-- anArrowSize and the text aText.
    returns mutable RadiusDimension from AIS;

    SetFirstShape( me: mutable; aFShape : Shape from TopoDS )
    is redefined static; 
    
    KindOfDimension(me) 
    	---Purpose: Indicates that the dimension selected is a radius.
    	---C++: inline
    returns KindOfDimension from AIS 
    is redefined;
    
    IsMovable(me) returns Boolean from Standard 
        ---C++: inline    
        ---Purpose: Returns true if the radius selected is movable.
    is redefined;    
    
    DrawFromCenter(me) returns Boolean from Standard
    	---Purpose:
    	-- Draws an arrowhead pointing towards the center of
    	-- the shape aShape defined at construction time if
    	-- false, and away from the center if true.
        ---C++: inline
    is static;
    
    SetDrawFromCenter(me: mutable;
    	    	      drawfromcenter : Boolean from Standard)
       ---C++: inline
       ---Purpose:
       -- Sets the Boolean drawfromcenter to true or false.
       -- If drawfromcenter is false, the arrowhead will point
       -- towards the center of the shape aShape defined at
       -- construction time.
    is static;
    
    -- Methods from PresentableObject

    Compute(me            : mutable;
    	    aPresentationManager: PresentationManager3d from PrsMgr;
    	    aPresentation : mutable Presentation from Prs3d;
    	    aMode         : Integer from Standard= 0) 
    is redefined private;
    
    Compute(me:mutable;
    	        aProjector: Projector from Prs3d;
                aPresentation: mutable Presentation from Prs3d)
    is redefined static private;     

    Compute(me:mutable;
    	    aPresentationManager: PresentationManager2d from PrsMgr;
            aPresentation: mutable GraphicObject from Graphic2d;
            aMode: Integer from Standard = 0)
    is redefined static private;	
    
    Compute(me            : mutable;
    	    aProjector    : Projector from Prs3d;
    	    aTrsf         : Transformation from Geom;
	    aPresentation : mutable Presentation from Prs3d)
    is redefined;
    	---Purpose: computes the presentation according to a point of view
    	--          given by <aProjector>. 
    	--          To be Used when the associated degenerated Presentations 
    	--          have been transformed by <aTrsf> which is not a Pure
    	--          Translation. The HLR Prs can't be deducted automatically
    	--          WARNING :<aTrsf> must be applied
    	--           to the object to display before computation  !!!

-- Methods from SelectableObject

    ComputeSelection(me         : mutable;
    	    	     aSelection : mutable Selection from SelectMgr;
    	    	     aMode      : Integer from Standard)
    is redefined private;

    
--
--     Computation private methods
--

    ComputeRadius( me: mutable; aPresentation : mutable Presentation from Prs3d )
    is private;  
     
    InitFirstShape( me: mutable) 
    is  static  private; 
    
fields

    myCircle         : Circ    from gp; 
    myFirstPar       : Real    from Standard; 
    myLastPar        : Real    from Standard; 
    myCenter         : Pnt     from gp; 
    myEndOfArrow     : Pnt     from gp; 
    myFirstLine      : Lin     from gp; 
    myLastLine       : Lin     from gp;
    mydrawFromCenter : Boolean from Standard;
    
end RadiusDimension;