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#include <GProp_GProps.ixx>
#include <GProp.hxx>
#include <math_Jacobi.hxx>
#include <gp.hxx>
#include <gp.hxx>
#include <gp_XYZ.hxx>
#include <gp_Vec.hxx>
GProp_GProps::GProp_GProps () : g (gp::Origin()) , loc (gp::Origin()), dim (0.0)
{
inertia = gp_Mat(0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0);
}
GProp_GProps::GProp_GProps (const gp_Pnt& SystemLocation) :
g (gp::Origin()), loc (SystemLocation), dim (0.0)
{
inertia = gp_Mat(0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0);
}
void GProp_GProps::Add (const GProp_GProps& Item, const Standard_Real Density) {
if (Density <= gp::Resolution()) Standard_DomainError::Raise();
if (loc.Distance (Item.loc) <= gp::Resolution ()) {
gp_XYZ GXYZ = (Item.g.XYZ()).Multiplied (Item.dim * Density);
g.SetXYZ (g.XYZ().Multiplied (dim));
GXYZ.Add (g.XYZ());
dim = dim + Item.dim * Density;
if (Abs(dim) >= 1.e-20 ) {
GXYZ.Divide (dim);
g.SetXYZ (GXYZ);
}
else {
g.SetCoord(0., 0., 0.);
}
inertia = inertia + Item.inertia * Density;
}else{
gp_XYZ Itemloc = loc.XYZ() - Item.loc.XYZ();
gp_XYZ Itemg = Item.loc.XYZ() + Item.g.XYZ();
gp_XYZ GXYZ = Item.g.XYZ() - Itemloc;
GXYZ = GXYZ.Multiplied (Item.dim * Density);
g.SetXYZ (g.XYZ().Multiplied (dim));
GXYZ.Add (g.XYZ());
dim = dim + Item.dim * Density;
if (Abs(dim) >= 1.e-20 ) {
GXYZ.Divide (dim);
g.SetXYZ (GXYZ);
}
else {
g.SetCoord(0., 0., 0.);
}
//We have to compute the inertia of the Item at the location point
//of the system using the Huyghens theorem
gp_Mat HMat;
gp_Mat ItemInertia = Item.inertia;
if (Item.g.XYZ().Modulus() > gp::Resolution()) {
//Computes the inertia of Item at its dim centre
GProp::HOperator (Itemg, Item.loc, Item.dim, HMat);
ItemInertia = ItemInertia - HMat;
}
//Computes the inertia of Item at the location point of the system
GProp::HOperator (Itemg, loc, Item.dim, HMat);
ItemInertia = ItemInertia + HMat;
inertia = inertia + ItemInertia * Density;
}
}
Standard_Real GProp_GProps::Mass () const { return dim; }
gp_Pnt GProp_GProps::CentreOfMass () const
{
return gp_Pnt(loc.XYZ() + g.XYZ());
}
gp_Mat GProp_GProps::MatrixOfInertia () const {
gp_Mat HMat;
GProp::HOperator (g,gp::Origin(),dim, HMat);
return inertia - HMat;
}
void GProp_GProps::StaticMoments (Standard_Real& Ix,
Standard_Real& Iy,
Standard_Real& Iz) const {
gp_XYZ G = loc.XYZ() + g.XYZ();
Ix = G.X() * dim;
Iy = G.Y() * dim;
Iz = G.Z() * dim;
}
Standard_Real GProp_GProps::MomentOfInertia (const gp_Ax1& A) const {
// Moment of inertia / axis A
// 1] computes the math_Matrix of inertia / A.location()
// 2] applies this math_Matrix to A.Direction()
// 3] then computes the scalar product between this vector and
// A.Direction()
if (loc.Distance (A.Location()) <= gp::Resolution()) {
return (A.Direction().XYZ()).Dot (
(A.Direction().XYZ()).Multiplied (inertia));
}
else {
gp_Mat HMat;
gp_Mat AxisInertia = MatrixOfInertia();
GProp::HOperator (gp_Pnt (loc.XYZ() + g.XYZ()), A.Location(), dim, HMat);
AxisInertia = AxisInertia + HMat;
return (A.Direction().XYZ()).Dot (
(A.Direction().XYZ()).Multiplied (AxisInertia));
}
}
Standard_Real GProp_GProps::RadiusOfGyration (const gp_Ax1& A) const {
return Sqrt (MomentOfInertia (A) / dim);
}
GProp_PrincipalProps GProp_GProps::PrincipalProperties () const {
math_Matrix DiagMat (1, 3, 1, 3);
Standard_Integer i, j;
gp_Mat AxisInertia = MatrixOfInertia();
for (j = 1; j <= 3; j++) {
for (i = 1; i <= 3; i++) {
DiagMat (i, j) = AxisInertia.Value (i, j);
}
}
math_Jacobi J (DiagMat);
Standard_Real Ixx = J.Value (1);
Standard_Real Iyy = J.Value (2);
Standard_Real Izz = J.Value (3);
DiagMat = J.Vectors ();
gp_Vec Vxx (DiagMat (1,1), DiagMat (2, 1), DiagMat (3, 1));
gp_Vec Vyy (DiagMat (1,2), DiagMat (2, 2), DiagMat (3, 2));
gp_Vec Vzz (DiagMat (1,3), DiagMat (2, 3), DiagMat (3, 3));
//
// protection contre dim == 0.0e0 au cas ou on aurait rentre qu'un point
//
Standard_Real Rxx = 0.0e0 ;
Standard_Real Ryy = 0.0e0 ;
Standard_Real Rzz = 0.0e0 ;
if (0.0e0 != dim) {
Rxx = Sqrt (Abs(Ixx / dim));
Ryy = Sqrt (Abs(Iyy / dim));
Rzz = Sqrt (Abs(Izz / dim));
}
return GProp_PrincipalProps (Ixx, Iyy, Izz, Rxx, Ryy, Rzz, Vxx, Vyy, Vzz,
gp_Pnt(g.XYZ() + loc.XYZ()));
}
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