-- File:	VrmlConverter_ShadingAspect.cdl
-- Created:	Wed Mar 12 17:07:28 1997
-- Author:	Alexander BRIVIN
--		<brivin@minox.nizhny.matra-dtv.fr>
---Copyright:	 Matra Datavision 1997


class ShadingAspect from VrmlConverter inherits TShared from MMgt

	---Purpose: qualifies the aspect properties for  
	--          the VRML conversation of ShadedShape . 

uses 

    Material    from   Vrml,
    ShapeHints  from   Vrml

is
 
    Create
    ---Purpose: create a default ShadingAspect.
    returns mutable ShadingAspect from VrmlConverter;
 
    SetFrontMaterial(me: mutable; aMaterial: Material from Vrml)
    is static;
 
    FrontMaterial(me) returns mutable Material from Vrml 
    is  static; 
    
--    SetBackMaterial(me: mutable; aMaterial: Material from Vrml)
--    is static;

    SetShapeHints ( me : mutable; aShapeHints  :  ShapeHints  from  Vrml  ) 
    is static;
 
    ShapeHints ( me )  returns  ShapeHints  from  Vrml;

    SetHasNormals (me: mutable; OnOff: Boolean from Standard)
    ---Purpose: defines necessary of  a  calculation  of  normals for  ShadedShape  to  more  
    --          accurately  display  curved  surfaces,  pacticularly  when  smoooth  or  phong   
    --          shading  is  used  in  VRML  viewer. 
    --          By default False  -  the normals are not calculated, 
    --          True  -  the normals are calculated. 
    --          Warning: If  normals  are  calculated  the  resulting  VRML  file  will   
    --          be  substantially  lager.
    is static;
    
    HasNormals(me) returns Boolean from Standard 
    ---Purpose: returns True if the normals are calculating 
    is static;
 
    SetHasMaterial(me: mutable; OnOff: Boolean from Standard)
    ---Purpose: defines necessary of writing  Material from Vrml into  output  OStream. 
    --          By default False  -  the material is not writing into OStream, 
    --          True  -  the material is writing. 
    is  static; 

    HasMaterial(me) returns Boolean from Standard 
    ---Purpose: returns True if the  materials is  writing into OStream.
    is static;


fields
     
    myFrontMaterial		:	Material    from   Vrml;
--    myBackMaterial		:	Material    from   Vrml;
    myShapeHints                :       ShapeHints  from   Vrml;  
    myHasNormals                :       Boolean  from  Standard;
    myHasMaterial               :       Boolean  from  Standard;

end ShadingAspect;