// Created on: 1996-02-13 // Created by: Yves FRICAUD // 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 _BRepOffsetAPI_MakeOffsetShape_HeaderFile #define _BRepOffsetAPI_MakeOffsetShape_HeaderFile #include #include #include #include #include #include #include #include #include #include #include class TopoDS_Shape; //! Describes functions to build a shell out of a shape. The //! result is an unlooped shape parallel to the source shape. //! A MakeOffsetShape object provides a framework for: //! - defining the construction of a shell //! - implementing the construction algorithm //! - consulting the result. class BRepOffsetAPI_MakeOffsetShape : public BRepBuilderAPI_MakeShape { public: DEFINE_STANDARD_ALLOC //! Constructor does nothing. Standard_EXPORT BRepOffsetAPI_MakeOffsetShape(); //! Constructs offset shape for the given one using simple algorithm without intersections computation. Standard_EXPORT void PerformBySimple(const TopoDS_Shape& theS, const Standard_Real theOffsetValue); //! Constructs a shape parallel to the shape S, where //! - S may be a face, a shell, a solid or a compound of these shape kinds; //! - Offset is the offset value. The offset shape is constructed: //! - outside S, if Offset is positive, //! - inside S, if Offset is negative; //! - Tol defines the coincidence tolerance criterion for generated shapes; //! - Mode defines the construction type of parallels //! applied to the free edges of shape S; currently, only one //! construction type is implemented, namely the one where the free //! edges do not generate parallels; this corresponds to the default //! value BRepOffset_Skin; //! - Intersection specifies how the algorithm must work in //! order to limit the parallels to two adjacent shapes: //! - if Intersection is false (default value), the intersection //! is calculated with the parallels to the two adjacent shapes, //! - if Intersection is true, the intersection is calculated by //! taking all generated parallels into account; this computation method is //! more general as it avoids some self-intersections generated in the //! offset shape from features of small dimensions on shape S, however this //! method has not been completely implemented and therefore is not //! recommended for use; //! - SelfInter tells the algorithm whether a computation //! to eliminate self-intersections must be applied to the resulting //! shape; however, as this functionality is not yet //! implemented, it is recommended to use the default value (false); //! - Join defines how to fill the holes that may appear between //! parallels to the two adjacent faces. It may take values //! GeomAbs_Arc or GeomAbs_Intersection: //! - if Join is equal to GeomAbs_Arc, then pipes are generated //! between two free edges of two adjacent parallels, //! and spheres are generated on "images" of vertices; //! it is the default value, //! - if Join is equal to GeomAbs_Intersection, then the parallels to the //! two adjacent faces are enlarged and intersected, //! so that there are no free edges on parallels to faces. //! RemoveIntEdges flag defines whether to remove the INTERNAL edges //! from the result or not. //! Warnings //! 1. All the faces of the shape S should be based on the surfaces //! with continuity at least C1. //! 2. The offset value should be sufficiently small to avoid //! self-intersections in resulting shape. Otherwise these //! self-intersections may appear inside an offset face if its //! initial surface is not plane or sphere or cylinder, also some //! non-adjacent offset faces may intersect each other. Also, some //! offset surfaces may "turn inside out". //! 3. The algorithm may fail if the shape S contains vertices where //! more than 3 edges converge. //! 4. Since 3d-offset algorithm involves intersection of surfaces, //! it is under limitations of surface intersection algorithm. //! 5. A result cannot be generated if the underlying geometry of S is //! BSpline with continuity C0. //! Exceptions //! Geom_UndefinedDerivative if the underlying //! geometry of S is BSpline with continuity C0. Standard_EXPORT void PerformByJoin(const TopoDS_Shape& S, const Standard_Real Offset, const Standard_Real Tol, const BRepOffset_Mode Mode = BRepOffset_Skin, const Standard_Boolean Intersection = Standard_False, const Standard_Boolean SelfInter = Standard_False, const GeomAbs_JoinType Join = GeomAbs_Arc, const Standard_Boolean RemoveIntEdges = Standard_False, const Message_ProgressRange& theRange = Message_ProgressRange()); //! Returns instance of the unrelying intersection / arc algorithm. Standard_EXPORT virtual const BRepOffset_MakeOffset& MakeOffset() const; //! Does nothing. Standard_EXPORT virtual void Build(const Message_ProgressRange& theRange = Message_ProgressRange()) Standard_OVERRIDE; //! Returns the list of shapes generated from the shape . Standard_EXPORT virtual const TopTools_ListOfShape& Generated (const TopoDS_Shape& S) Standard_OVERRIDE; //! Returns the list of shapes Modified from the shape . Standard_EXPORT virtual const TopTools_ListOfShape& Modified (const TopoDS_Shape& S) Standard_OVERRIDE; //! Returns true if the shape has been removed from the result. Standard_EXPORT virtual Standard_Boolean IsDeleted (const TopoDS_Shape& S) Standard_OVERRIDE; //! Returns offset join type. Standard_EXPORT GeomAbs_JoinType GetJoinType() const; protected: enum OffsetAlgo_Type { OffsetAlgo_NONE, OffsetAlgo_JOIN, OffsetAlgo_SIMPLE }; OffsetAlgo_Type myLastUsedAlgo; BRepOffset_MakeOffset myOffsetShape; BRepOffset_MakeSimpleOffset mySimpleOffsetShape; }; #endif // _BRepOffsetAPI_MakeOffsetShape_HeaderFile