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// This file is generated by WOK (CPPExt).
// Please do not edit this file; modify original file instead.
// The copyright and license terms as defined for the original file apply to
// this header file considered to be the "object code" form of the original source.
#ifndef _GProp_PrincipalProps_HeaderFile
#define _GProp_PrincipalProps_HeaderFile
#include <Standard.hxx>
#include <Standard_DefineAlloc.hxx>
#include <Standard_Macro.hxx>
#include <Standard_Real.hxx>
#include <gp_Vec.hxx>
#include <gp_Pnt.hxx>
#include <GProp_GProps.hxx>
#include <Standard_Boolean.hxx>
class GProp_UndefinedAxis;
class gp_Vec;
class gp_Pnt;
//! A framework to present the principal properties of
//! inertia of a system of which global properties are
//! computed by a GProp_GProps object.
//! There is always a set of axes for which the
//! products of inertia of a geometric system are equal
//! to 0; i.e. the matrix of inertia of the system is
//! diagonal. These axes are the principal axes of
//! inertia. Their origin is coincident with the center of
//! mass of the system. The associated moments are
//! called the principal moments of inertia.
//! This sort of presentation object is created, filled and
//! returned by the function PrincipalProperties for
//! any GProp_GProps object, and can be queried to access the result.
//! Note: The system whose principal properties of
//! inertia are returned by this framework is referred to
//! as the current system. The current system,
//! however, is retained neither by this presentation
//! framework nor by the GProp_GProps object which activates it.
class GProp_PrincipalProps
{
public:
DEFINE_STANDARD_ALLOC
//! creates an undefined PrincipalProps.
Standard_EXPORT GProp_PrincipalProps();
//! returns true if the geometric system has an axis of symmetry.
//! For comparing moments relative tolerance 1.e-10 is used.
//! Usually it is enough for objects, restricted by faces with
//! analitycal geometry.
Standard_EXPORT Standard_Boolean HasSymmetryAxis() const;
//! returns true if the geometric system has an axis of symmetry.
//! aTol is relative tolerance for cheking equality of moments
//! If aTol == 0, relative tolerance is ~ 1.e-16 (Epsilon(I))
Standard_EXPORT Standard_Boolean HasSymmetryAxis (const Standard_Real aTol) const;
//! returns true if the geometric system has a point of symmetry.
//! For comparing moments relative tolerance 1.e-10 is used.
//! Usually it is enough for objects, restricted by faces with
//! analitycal geometry.
Standard_EXPORT Standard_Boolean HasSymmetryPoint() const;
//! returns true if the geometric system has a point of symmetry.
//! aTol is relative tolerance for cheking equality of moments
//! If aTol == 0, relative tolerance is ~ 1.e-16 (Epsilon(I))
Standard_EXPORT Standard_Boolean HasSymmetryPoint (const Standard_Real aTol) const;
//! Ixx, Iyy and Izz return the principal moments of inertia
//! in the current system.
//! Notes :
//! - If the current system has an axis of symmetry, two
//! of the three values Ixx, Iyy and Izz are equal. They
//! indicate which eigen vectors define an infinity of
//! axes of principal inertia.
//! - If the current system has a center of symmetry, Ixx,
//! Iyy and Izz are equal.
Standard_EXPORT void Moments (Standard_Real& Ixx, Standard_Real& Iyy, Standard_Real& Izz) const;
//! returns the first axis of inertia.
//!
//! if the system has a point of symmetry there is an infinity of
//! solutions. It is not possible to defines the three axis of
//! inertia.
Standard_EXPORT const gp_Vec& FirstAxisOfInertia() const;
//! returns the second axis of inertia.
//!
//! if the system has a point of symmetry or an axis of symmetry the
//! second and the third axis of symmetry are undefined.
Standard_EXPORT const gp_Vec& SecondAxisOfInertia() const;
//! returns the third axis of inertia.
//! This and the above functions return the first, second or third eigen vector of the
//! matrix of inertia of the current system.
//! The first, second and third principal axis of inertia
//! pass through the center of mass of the current
//! system. They are respectively parallel to these three eigen vectors.
//! Note that:
//! - If the current system has an axis of symmetry, any
//! axis is an axis of principal inertia if it passes
//! through the center of mass of the system, and runs
//! parallel to a linear combination of the two eigen
//! vectors of the matrix of inertia, corresponding to the
//! two eigen values which are equal. If the current
//! system has a center of symmetry, any axis passing
//! through the center of mass of the system is an axis
//! of principal inertia. Use the functions
//! HasSymmetryAxis and HasSymmetryPoint to
//! check these particular cases, where the returned
//! eigen vectors define an infinity of principal axis of inertia.
//! - The Moments function can be used to know which
//! of the three eigen vectors corresponds to the two
//! eigen values which are equal.
//!
//! if the system has a point of symmetry or an axis of symmetry the
//! second and the third axis of symmetry are undefined.
Standard_EXPORT const gp_Vec& ThirdAxisOfInertia() const;
//! Returns the principal radii of gyration Rxx, Ryy
//! and Rzz are the radii of gyration of the current
//! system about its three principal axes of inertia.
//! Note that:
//! - If the current system has an axis of symmetry,
//! two of the three values Rxx, Ryy and Rzz are equal.
//! - If the current system has a center of symmetry,
//! Rxx, Ryy and Rzz are equal.
Standard_EXPORT void RadiusOfGyration (Standard_Real& Rxx, Standard_Real& Ryy, Standard_Real& Rzz) const;
friend
//! Computes the principal properties of inertia of the current system.
//! There is always a set of axes for which the products
//! of inertia of a geometric system are equal to 0; i.e. the
//! matrix of inertia of the system is diagonal. These axes
//! are the principal axes of inertia. Their origin is
//! coincident with the center of mass of the system. The
//! associated moments are called the principal moments of inertia.
//! This function computes the eigen values and the
//! eigen vectors of the matrix of inertia of the system.
//! Results are stored by using a presentation framework
//! of principal properties of inertia
//! (GProp_PrincipalProps object) which may be
//! queried to access the value sought.
Standard_EXPORT GProp_PrincipalProps GProp_GProps::PrincipalProperties() const;
protected:
private:
Standard_EXPORT GProp_PrincipalProps(const Standard_Real Ixx, const Standard_Real Iyy, const Standard_Real Izz, const Standard_Real Rxx, const Standard_Real Ryy, const Standard_Real Rzz, const gp_Vec& Vxx, const gp_Vec& Vyy, const gp_Vec& Vzz, const gp_Pnt& G);
Standard_Real i1;
Standard_Real i2;
Standard_Real i3;
Standard_Real r1;
Standard_Real r2;
Standard_Real r3;
gp_Vec v1;
gp_Vec v2;
gp_Vec v3;
gp_Pnt g;
};
#endif // _GProp_PrincipalProps_HeaderFile
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