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#include <LProp_Status.hxx>
#include <LProp_NotDefined.hxx>
#include <Standard_OutOfRange.hxx>
LProp_CLProps::LProp_CLProps (const Curve& C,
const Standard_Real U,
const Standard_Integer N,
const Standard_Real Resolution)
: myCurve(C),
level(N),
cn(4), // cn(Tool::Continuity(C)), RLE
linTol(Resolution),
tangentStatus (LProp_Undecided)
{
Standard_OutOfRange_Raise_if (N < 0 || N > 3,
"LProp_CLProps::LProp_CLProps()");
SetParameter(U);
}
LProp_CLProps::LProp_CLProps (const Curve& C,
const Standard_Integer N,
const Standard_Real Resolution)
: myCurve(C),
u(RealLast()),
level(N),
cn(4), // (Tool::Continuity(C)), RLE
linTol(Resolution),
tangentStatus (LProp_Undecided)
{
Standard_OutOfRange_Raise_if (N < 0 || N > 3, "");
}
LProp_CLProps::LProp_CLProps (const Standard_Integer N,
const Standard_Real Resolution)
: u(RealLast()),
level(N),
cn(0),
linTol(Resolution),
tangentStatus (LProp_Undecided)
{
Standard_OutOfRange_Raise_if (N < 0 || N > 3, "");
}
void LProp_CLProps::SetParameter(const Standard_Real U)
{
u = U;
switch (level) {
case 0:
Tool::Value(myCurve, u, pnt);
break;
case 1:
Tool::D1(myCurve, u, pnt, d[0]);
break;
case 2:
Tool::D2(myCurve, u, pnt, d[0], d[1]);
break;
case 3:
Tool::D3(myCurve, u, pnt, d[0], d[1], d[2]);
break;
}
tangentStatus = LProp_Undecided;
}
void LProp_CLProps::SetCurve(const Curve& C) {
myCurve = C ;
cn = 4; // Tool::Continuity(C); RLE
}
const Pnt& LProp_CLProps::Value () const
{
return pnt;
}
const Vec& LProp_CLProps::D1 ()
{
if (level < 1) {
level = 1;
Tool::D1(myCurve, u, pnt, d[0]);
}
return d[0];
}
const Vec& LProp_CLProps::D2 ()
{
if (level < 2) {
level = 2;
Tool::D2(myCurve, u, pnt, d[0], d[1]);
}
return d[1];
}
const Vec& LProp_CLProps::D3 ()
{
if (level < 3) {
level = 3;
Tool::D3(myCurve, u, pnt, d[0], d[1], d[2]);
}
return d[2];
}
Standard_Boolean LProp_CLProps::IsTangentDefined ()
{
if (tangentStatus == LProp_Undefined) {
return Standard_False;
}
else if (tangentStatus >= LProp_Defined) {
return Standard_True;
}
// tangentStatus == Lprop_Undecided
// we have to calculate the first non null derivative
Standard_Real Tol = linTol * linTol;
Vec V;
Standard_Integer Order = 0;
while (Order < 4) {
Order++;
if(cn >= Order) {
switch(Order) {
case 1 :
V = D1();
break;
case 2 :
V = D2();
break;
case 3 :
V = D3();
break;
};
if(V.SquareMagnitude() > Tol) {
significantFirstDerivativeOrder = Order;
tangentStatus = LProp_Defined;
return Standard_True;
}
}
else {
tangentStatus = LProp_Undefined;
return Standard_False;
}
}
return Standard_False;
}
void LProp_CLProps::Tangent (Dir& D)
{
if(!IsTangentDefined()) { LProp_NotDefined::Raise(); }
D = Dir(d[significantFirstDerivativeOrder - 1]);
}
Standard_Real LProp_CLProps::Curvature ()
{
Standard_Boolean isDefined = IsTangentDefined();
LProp_NotDefined_Raise_if(!isDefined,
"LProp_CLProps::CurvatureNotDefined()");
// if the first derivative is null the curvature is infinite.
if(significantFirstDerivativeOrder > 1) return RealLast();
Standard_Real Tol = linTol * linTol;
Standard_Real DD1 = d[0].SquareMagnitude();
Standard_Real DD2 = d[1].SquareMagnitude();
// if the second derivative is null the curvature is null.
if (DD2 <= Tol) {
curvature = 0.0;
}
else {
Standard_Real N = d[0].CrossSquareMagnitude(d[1]);
// if d[0] and d[1] are colinear the curvature is null.
Standard_Real t = N/(DD1*DD2);
if (t<=Tol) {
curvature = 0.0;
}
else {
curvature = sqrt(N) / (DD1*sqrt(DD1));
}
}
return curvature;
}
void LProp_CLProps::Normal (Dir& D)
{
Standard_Real c = Curvature();
if(c==RealLast() || Abs(c) <= linTol) { LProp_NotDefined::Raise(); }
// we used here the following vector relation
// a ^ (b ^ c) = b(ac) - c(ab)
// Norm = d[0] ^ (d[1] ^ d[0])
Vec Norm = d[1] * (d[0] * d[0]) - d[0] * (d[0] * d[1]);
D = Dir(Norm);
}
void LProp_CLProps::CentreOfCurvature (Pnt& P)
{
if(Abs(Curvature()) <= linTol) { LProp_NotDefined::Raise(); }
// we used here the following vector relation
// a ^ (b ^ c) = b(ac) - c(ab)
// Norm = d[0] ^ (d[1] ^ d[0])
Vec Norm = d[1] * (d[0] * d[0]) - d[0] * (d[0] * d[1]);
Norm.Normalize();
Norm.Divide(curvature);
P= pnt.Translated(Norm);
}
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