include/opencascade/GProp.hxx

0001 // Created on: 1991-03-12
0002 // Created by: Michel CHAUVAT
0003 // Copyright (c) 1991-1999 Matra Datavision
0004 // Copyright (c) 1999-2014 OPEN CASCADE SAS
0005 //
0006 // This file is part of Open CASCADE Technology software library.
0007 //
0008 // This library is free software; you can redistribute it and/or modify it under
0009 // the terms of the GNU Lesser General Public License version 2.1 as published
0010 // by the Free Software Foundation, with special exception defined in the file
0011 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
0012 // distribution for complete text of the license and disclaimer of any warranty.
0013 //
0014 // Alternatively, this file may be used under the terms of Open CASCADE
0015 // commercial license or contractual agreement.
0016
0017 #ifndef _GProp_HeaderFile
0018 #define _GProp_HeaderFile
0019
0020 #include <Standard.hxx>
0021 #include <Standard_DefineAlloc.hxx>
0022 #include <Standard_Handle.hxx>
0023
0024 #include <Standard_Real.hxx>
0025 class gp_Pnt;
0026 class gp_Mat;
0027
0028
0029
0030 //! This package defines algorithms to compute the global properties
0031 //! of a set of points, a curve, a surface, a solid (non infinite
0032 //! region of space delimited with geometric entities), a compound
0033 //! geometric system (heterogeneous composition of the previous
0034 //! entities).
0035 //!
0036 //! Global properties are :
0037 //! . length, area, volume,
0038 //! . centre of mass,
0039 //! . axis of inertia,
0040 //! . moments of inertia,
0041 //! . radius of gyration.
0042 //!
0043 //! It provides  also a class to  compile the average point or
0044 //! line of a set of points.
0045 class GProp
0046 {
0047 public:
0048
0049   DEFINE_STANDARD_ALLOC
0050
0051
0052   //! methods of package
0053   //! Computes the matrix Operator, referred to as the
0054   //! "Huyghens Operator" of a geometric system at the
0055   //! point Q of the space, using the following data :
0056   //! - Mass, i.e. the mass of the system,
0057   //! - G, the center of mass of the system.
0058   //! The "Huyghens Operator" is used to compute
0059   //! Inertia/Q, the matrix of inertia of the system at
0060   //! the point Q using Huyghens' theorem :
0061   //! Inertia/Q = Inertia/G + HOperator (Q, G, Mass)
0062   //! where Inertia/G is the matrix of inertia of the
0063   //! system relative to its center of mass as returned by
0064   //! the function MatrixOfInertia on any GProp_GProps object.
0065   Standard_EXPORT static void HOperator (const gp_Pnt& G, const gp_Pnt& Q, const Standard_Real Mass, gp_Mat& Operator);
0066
0067 };
0068
0069 #endif // _GProp_HeaderFile