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[TD]fix conversion of BSpline to Circle/Arc

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wandererfan
2024-05-20 12:41:03 -04:00
committed by WandererFan
parent 40a1ac8c8b
commit 5003dc2733
2 changed files with 30 additions and 98 deletions
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126
src/Mod/TechDraw/App/Geometry.cpp
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@@ -42,6 +42,10 @@
# include <BRepTools.hxx>
# include <GC_MakeArcOfCircle.hxx>
# include <GC_MakeEllipse.hxx>
#include <GC_MakeCircle.hxx>
#include <Geom_TrimmedCurve.hxx>
#include <Geom_Circle.hxx>
# include <gce_MakeCirc.hxx>
# include <GCPnts_AbscissaPoint.hxx>
# include <GProp_GProps.hxx>
@@ -75,6 +79,7 @@
#include <Base/Console.h>
#include <Base/Parameter.h>
#include <Base/Reader.h>
#include <Base/Tools.h>
#include <Base/Writer.h>
#include <Mod/Part/App/Geometry.h>
@@ -1579,112 +1584,39 @@ bool GeometryUtils::getCircleParms(TopoDS_Edge occEdge, double& radius, Base::Ve
return isCircle;
}
// make a circle or arc of circle Edge from BSpline Edge
TopoDS_Edge GeometryUtils::asCircle(TopoDS_Edge occEdge, bool& arc)
//! make a circle or arc of circle Edge from BSpline Edge
//! assumes the spline is generally circular but does not check
TopoDS_Edge GeometryUtils::asCircle(TopoDS_Edge splineEdge, bool& arc)
{
TopoDS_Edge result;
BRepAdaptor_Curve c(occEdge);
BRepAdaptor_Curve curveAdapt(splineEdge);
// find the two ends
Handle(Geom_Curve) curve = c.Curve().Curve();
double f = c.FirstParameter();
double l = c.LastParameter();
gp_Pnt s = c.Value(f);
gp_Pnt e = c.Value(l);
// find the ends of the edge from the underlying curve
Handle(Geom_Curve) curve = curveAdapt.Curve().Curve();
double firstParam = curveAdapt.FirstParameter();
double lastParam = curveAdapt.LastParameter();
gp_Pnt startPoint = curveAdapt.Value(firstParam);
gp_Pnt endPoint = curveAdapt.Value(lastParam);
if (s.IsEqual(e, 0.001)) { //more reliable
arc = true;
if (startPoint.IsEqual(endPoint, 0.001)) { //more reliable than IsClosed flag
arc = false;
} else {
arc = true;
}
// arc = !c.IsClosed(); //reliable?
double midRange = (lastParam + firstParam) / 2;
gp_Pnt midPoint = curveAdapt.Value(midRange);
Handle_Geom_Circle circle3Points = GC_MakeCircle(startPoint, midPoint, endPoint);
Handle(Geom_BSplineCurve) spline = c.BSpline();
if (spline->NbPoles() < 5) { //need 5 poles (s-p1-pm-p2-e) for algo
return result; //how to do with fewer poles?
if (circle3Points.IsNull()) {
return {};
}
try {
// get three points on curve (non extreme poles)
int nb_poles = spline->NbPoles();
gp_Pnt p1 = spline->Pole(2); //OCC numbering starts at 1!!
gp_Pnt p2 = spline->Pole(nb_poles-1);
gp_Pnt pm;
if (nb_poles == 5) {
pm = spline->Pole(3); //5 poles => 2.5 => 2
} else {
pm = spline->Pole(nb_poles / 2);
}
// project three poles onto the curve
GeomAPI_ProjectPointOnCurve proj1;
GeomAPI_ProjectPointOnCurve proj2;
GeomAPI_ProjectPointOnCurve projm;
proj1.Init(p1, curve, f, l);
proj1.Perform(p1);
proj2.Init(p2, curve, f, l);
proj2.Perform(p2);
projm.Init(pm, curve, f, l);
projm.Perform(pm);
if ( (proj1.NbPoints() == 0) ||
(proj2.NbPoints() == 0) ||
(projm.NbPoints() == 0) ) {
return result;
}
gp_Pnt pc1, pc2, pcm;
// get projected points
pc1 = proj1.NearestPoint();
pc2 = proj2.NearestPoint();
pcm = projm.NearestPoint();
// make 2 circles and find their radii
gce_MakeCirc gce_circ1 = gce_MakeCirc(s, pc1, pcm); //3 point circle
if (gce_circ1.Status() != gce_Done) {
return result;
}
gp_Circ circle1 = gce_circ1.Value();
double radius1 = circle1.Radius();
gp_Pnt center1 = circle1.Location();
Base::Vector3d vc1 = DrawUtil::toVector3d(center1);
gce_MakeCirc gce_circ2 = gce_MakeCirc(pcm, pc2, e);
if (gce_circ2.Status() != gce_Done) {
return result;
}
gp_Circ circle2 = gce_circ2.Value();
double radius2 = circle2.Radius();
gp_Pnt center2 = circle2.Location();
Base::Vector3d vc2 = DrawUtil::toVector3d(center2);
// compare radii & centers
double allowError = 0.001; //mm^-3 good enough for printing
double radius;
Base::Vector3d center;
if ( (DrawUtil::fpCompare(radius2, radius1, allowError)) &&
(vc1.IsEqual(vc2, allowError)) ) {
if (arc) {
GC_MakeArcOfCircle makeArc(s, pcm, e);
Handle(Geom_TrimmedCurve) tCurve = makeArc.Value();
BRepBuilderAPI_MakeEdge mkEdge(tCurve);
result = mkEdge.Edge();
} else {
radius = (radius1 + radius2) / 2.0;
center = (vc1 + vc2) / 2.0;
gp_Pnt gCenter(center.x, center.y, center.z);
gp_Ax2 stdZ(gCenter, gp_Dir(0, 0, 1));
gp_Circ newCirc(stdZ, radius);
BRepBuilderAPI_MakeEdge mkEdge(newCirc);
result = mkEdge.Edge();
}
}
if (!arc) {
// whole circle
return BRepBuilderAPI_MakeEdge(circle3Points);
}
catch (...) {
// return null shape to indicate that we could not make a circle from this bspline
return TopoDS_Edge();
}
return result;
Handle_Geom_TrimmedCurve circleArc =
GC_MakeArcOfCircle (startPoint, midPoint, endPoint);
return BRepBuilderAPI_MakeEdge(circleArc);
}
bool GeometryUtils::isLine(TopoDS_Edge occEdge)

2
src/Mod/TechDraw/App/Geometry.h
View File

@@ -445,7 +445,7 @@ class TechDrawExport GeometryUtils
static bool isCircle(TopoDS_Edge occEdge);
static bool getCircleParms(TopoDS_Edge occEdge, double& radius, Base::Vector3d& center, bool& isArc);
static TopoDS_Edge asCircle(TopoDS_Edge occEdge, bool& arc);
static TopoDS_Edge asCircle(TopoDS_Edge splineEdge, bool& arc);
static bool isLine(TopoDS_Edge occEdge);
static TopoDS_Edge asLine(TopoDS_Edge occEdge);