text: // Created on: 1996-12-05
  // Created by: Jean-Pierre COMBE/Odile Olivier
  // Copyright (c) 1996-1999 Matra Datavision
  // Copyright (c) 1999-2014 OPEN CASCADE SAS
  //
  // This file is part of Open CASCADE Technology software library.
  //
  // This library is free software; you can redistribute it and/or modify it under
  // the terms of the GNU Lesser General Public License version 2.1 as published
  // by the Free Software Foundation, with special exception defined in the file
  // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
  // distribution for complete text of the license and disclaimer of any warranty.
  //
  // Alternatively, this file may be used under the terms of Open CASCADE
  // commercial license or contractual agreement.
  
  #ifndef _AIS_ParallelRelation_HeaderFile
  #define _AIS_ParallelRelation_HeaderFile
  
  #include <AIS_Relation.hxx>
  #include <DsgPrs_ArrowSide.hxx>
  
  DEFINE_STANDARD_HANDLE(AIS_ParallelRelation, AIS_Relation)
  
  //! A framework to display constraints of parallelism
  //! between two or more Interactive Objects. These
  //! entities can be faces or edges.
  class AIS_ParallelRelation : public AIS_Relation
  {
    DEFINE_STANDARD_RTTIEXT(AIS_ParallelRelation, AIS_Relation)
  public:
  
    
    //! Constructs an object to display parallel constraints.
    //! This object is defined by the first shape aFShape and
    //! the second shape aSShape and the plane aPlane.
    Standard_EXPORT AIS_ParallelRelation(const TopoDS_Shape& aFShape, const TopoDS_Shape& aSShape, const Handle(Geom_Plane)& aPlane);
    
    //! Constructs an object to display parallel constraints.
    //! This object is defined by the first shape aFShape and
    //! the second shape aSShape the plane aPlane, the
    //! position aPosition, the type of arrow, aSymbolPrs and
    //! its size anArrowSize.
    Standard_EXPORT AIS_ParallelRelation(const TopoDS_Shape& aFShape, const TopoDS_Shape& aSShape, const Handle(Geom_Plane)& aPlane, const gp_Pnt& aPosition, const DsgPrs_ArrowSide aSymbolPrs, const Standard_Real anArrowSize = 0.01);
    
    //! Returns true if the parallelism is movable.
      virtual Standard_Boolean IsMovable() const Standard_OVERRIDE;
    
    //! 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  !!!
    Standard_EXPORT virtual void Compute (const Handle(Prs3d_Projector)& aProjector, const Handle(Geom_Transformation)& aTrsf, const Handle(Prs3d_Presentation)& aPresentation) Standard_OVERRIDE;
  
  private:
  
    Standard_EXPORT void Compute (const Handle(PrsMgr_PresentationManager3d)& aPresentationManager, const Handle(Prs3d_Presentation)& aPresentation, const Standard_Integer aMode = 0) Standard_OVERRIDE;
    
    Standard_EXPORT void Compute (const Handle(Prs3d_Projector)& aProjector, const Handle(Prs3d_Presentation)& aPresentation) Standard_OVERRIDE;
    
    Standard_EXPORT void ComputeSelection (const Handle(SelectMgr_Selection)& aSelection, const Standard_Integer aMode) Standard_OVERRIDE;
    
    Standard_EXPORT void ComputeTwoFacesParallel (const Handle(Prs3d_Presentation)& aPresentation);
    
    Standard_EXPORT void ComputeTwoEdgesParallel (const Handle(Prs3d_Presentation)& aPresentation);
  
    gp_Pnt myFAttach;
    gp_Pnt mySAttach;
    gp_Dir myDirAttach;
  
  };
  
  #include <AIS_ParallelRelation.lxx>
  
  #endif // _AIS_ParallelRelation_HeaderFile
  