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0027804: Two breps cause intersections to loop for too long/infinitely

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In ProjLib_ComputeApprox algorithm, compute correct parametric tolerance from the input 3D tolerance using surface resolution, in order to pass it to low-level 2D algorithm Approx_FitAndDivide2d (instantiation of the generic class Approx_ComputeCLine). Earlier 3D tolerance was used as parametric tolerance directly, which was a problem for surfaces with too small radius of curvature.

Also, eliminate redundant creation of the object of type AppParCurves_MultiCurve on each iteration in the method Approx_ComputeCLine::Compute.

The post treatment of the Edge/Edge intersections has been improved. Namely:
a. Making the procedure of sharing Edge/Edge intersection vertices consistent with intersection algorithm by enlarging bounding box of each vertex on half of Precision::Confusion();
b. Algorithm of computation of vertex tolerance (in order to cover tangent zone between Edges) has been changed for Line/Circle cases.

Test cases for issue CR27804
Adjusting test cases according to their new behavior.

Mark the test boolean/volumemaker/A8 as unstable between different versions of MSVS (2010 and 2013).
This commit is contained in:
msv
2016-08-26 17:33:46 +03:00
committed by bugmaster
parent 84caaf81a0
commit 3065019c99
6 changed files with 136 additions and 15 deletions
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57
src/ProjLib/ProjLib_ComputeApprox.cxx
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@@ -893,6 +893,40 @@ class ProjLib_Function : public AppCont_Function
}
};
//=======================================================================
//function : ComputeTolU
//purpose :
//=======================================================================
static Standard_Real ComputeTolU(const Handle(Adaptor3d_HSurface)& theSurf,
const Standard_Real theTolerance)
{
Standard_Real aTolU = theSurf->UResolution(theTolerance);
if (theSurf->IsUPeriodic())
{
aTolU = Min(aTolU, 0.01*theSurf->UPeriod());
}
return aTolU;
}
//=======================================================================
//function : ComputeTolV
//purpose :
//=======================================================================
static Standard_Real ComputeTolV(const Handle(Adaptor3d_HSurface)& theSurf,
const Standard_Real theTolerance)
{
Standard_Real aTolV = theSurf->VResolution(theTolerance);
if (theSurf->IsVPeriodic())
{
aTolV = Min(aTolV, 0.01*theSurf->VPeriod());
}
return aTolV;
}
//=======================================================================
//function : ProjLib_ComputeApprox
//purpose :
@@ -1031,8 +1065,13 @@ ProjLib_ComputeApprox::ProjLib_ComputeApprox
Deg2 = 12;
}
//-------------
Approx_FitAndDivide2d Fit(F,Deg1,Deg2,myTolerance,myTolerance,
Standard_True);
const Standard_Real aTolU = ComputeTolU(S, myTolerance);
const Standard_Real aTolV = ComputeTolV(S, myTolerance);
const Standard_Real aTol2d = Max(Sqrt(aTolU*aTolU + aTolV*aTolV), Precision::PConfusion());
Approx_FitAndDivide2d Fit(F, Deg1, Deg2, myTolerance, aTol2d, Standard_True);
Standard_Real aNewTol2d = 0;
if(Fit.IsAllApproximated()) {
Standard_Integer i;
Standard_Integer NbCurves = Fit.NbMultiCurves();
@@ -1040,11 +1079,10 @@ ProjLib_ComputeApprox::ProjLib_ComputeApprox
// on essaie de rendre la courbe au moins C1
Convert_CompBezierCurves2dToBSplineCurve2d Conv;
myTolerance = 0;
Standard_Real Tol3d,Tol2d;
for (i = 1; i <= NbCurves; i++) {
Fit.Error(i,Tol3d, Tol2d);
myTolerance = Max(myTolerance, Tol2d);
aNewTol2d = Max(aNewTol2d, Tol2d);
AppParCurves_MultiCurve MC = Fit.Value( i); //Charge la Ieme Curve
TColgp_Array1OfPnt2d Poles2d( 1, MC.Degree() + 1);//Recupere les poles
MC.Curve(1, Poles2d);
@@ -1095,10 +1133,19 @@ ProjLib_ComputeApprox::ProjLib_ComputeApprox
if(NbCurves != 0) {
Standard_Real Tol3d,Tol2d;
Fit.Error(NbCurves,Tol3d, Tol2d);
myTolerance = Tol2d;
aNewTol2d = Tol2d;
}
}
// restore tolerance 3d from 2d
//Here we consider that
// aTolU(new)/aTolV(new) = aTolU(old)/aTolV(old)
//(it is assumption indeed).
//Then,
// Tol3D(new)/Tol3D(old) = Tol2D(new)/Tol2D(old).
myTolerance *= (aNewTol2d / aTol2d);
//Return curve home
Standard_Real UFirst = F.FirstParameter();
gp_Pnt P3d = C->Value( UFirst );