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#include <BOPAlgo_Builder.hxx>
#include <BRepAlgoAPI_Splitter.hxx>
#include <BRepBndLib.hxx>
#include <BRepBuilderAPI_Copy.hxx>
#include <BRepBuilderAPI_MakeFace.hxx>
#include <BRepBuilderAPI_Sewing.hxx>
#include <BRepBuilderAPI_Transform.hxx>
#include <BRep_Builder.hxx>
#include <BRep_Tool.hxx>
#include <Bnd_Box.hxx>
#include <Geom_Plane.hxx>
#include <Geom_Surface.hxx>
#include <Precision.hxx>
#include <ShapeBuild_ReShape.hxx>
#include <ShapeFix_Shape.hxx>
#include <Standard_Handle.hxx>
#include <Standard_TypeDef.hxx>
#include <TopAbs_ShapeEnum.hxx>
#include <TopExp_Explorer.hxx>
#include <TopTools_ListOfShape.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Face.hxx>
#include <TopoDS_Face.hxx>
#include <TopoDS_Shape.hxx>
#include <algorithm>
#include <gp.hxx>
#include <gp_Ax3.hxx>
#include <gp_Pln.hxx>
#include <gp_Trsf.hxx>
#include <limits>
#include "core/array.hpp"
#include "occ_utils.hpp"
#include "occgeom.hpp"
namespace netgen
{
TopoDS_Face MakePlaneFaceCoveringShape
(const TopoDS_Shape& shape,
const gp_Pln& pln,
double rel_margin = 0.05,
double abs_margin = 0.0)
{
Bnd_Box b;
BRepBndLib::Add(shape, b);
b.SetGap(0.0);
Standard_Real xmin, ymin, zmin, xmax, ymax, zmax;
b.Get(xmin, ymin, zmin, xmax, ymax, zmax);
gp_Trsf w2l;
w2l.SetTransformation(pln.Position());
auto upd = [&] (double x, double y, double z, double& umin, double& umax, double& vmin, double& vmax) {
gp_Pnt p(x, y, z);
p.Transform(w2l);
umin = std::min(umin, p.X());
umax = std::max(umax, p.X());
vmin = std::min(vmin, p.Y());
vmax = std::max(vmax, p.Y());
};
double umin = std::numeric_limits<double>::infinity();
double umax = -std::numeric_limits<double>::infinity();
double vmin = std::numeric_limits<double>::infinity();
double vmax = -std::numeric_limits<double>::infinity();
upd(xmin, ymin, zmin, umin, umax, vmin, vmax);
upd(xmin, ymin, zmax, umin, umax, vmin, vmax);
upd(xmin, ymax, zmin, umin, umax, vmin, vmax);
upd(xmin, ymax, zmax, umin, umax, vmin, vmax);
upd(xmax, ymin, zmin, umin, umax, vmin, vmax);
upd(xmax, ymin, zmax, umin, umax, vmin, vmax);
upd(xmax, ymax, zmin, umin, umax, vmin, vmax);
upd(xmax, ymax, zmax, umin, umax, vmin, vmax);
double du = umax - umin;
double dv = vmax - vmin;
double pad = std::max(abs_margin, rel_margin * std::max(du, dv));
umin -= pad;
umax += pad;
vmin -= pad;
vmax += pad;
double eps = std::max(Precision::Confusion(), 1e-9);
if (umax - umin < eps)
{
umin -= 1.0;
umax += 1.0;
}
if (vmax - vmin < eps)
{
vmin -= 1.0;
vmax += 1.0;
}
return BRepBuilderAPI_MakeFace(pln, umin, umax, vmin, vmax).Face();
}
TopoDS_Shape CrossSection (const TopoDS_Shape& shape,
const gp_Ax3& axes)
{
gp_Pln pln(axes);
TopoDS_Face planeFace = MakePlaneFaceCoveringShape(shape, axes);
auto bb = GetBoundingBox(shape);
auto diam = bb.Diam();
// Heal / unify the input
// - especially if shape comes from STEP/IGES
ShapeFix_Shape fix(shape);
fix.Perform();
TopoDS_Shape fixed = fix.Shape();
BRepAlgoAPI_Splitter splitter;
splitter.SetNonDestructive(true);
splitter.SetFuzzyValue(1e-7 * diam);
TopTools_ListOfShape args;
args.Append(shape);
TopTools_ListOfShape tools;
tools.Append(planeFace);
splitter.SetArguments(args);
splitter.SetTools(tools);
splitter.Build();
if (!splitter.IsDone())
return TopoDS_Shape();
// for each input face/edge propagate properties to generated sub-shapes
for (auto typ : {TopAbs_FACE, TopAbs_EDGE})
for (TopExp_Explorer e(shape, typ); e.More(); e.Next())
{
if (!OCCGeometry::HaveProperties(e.Current()))
continue;
auto prop = OCCGeometry::GetProperties(e.Current());
for (auto mods : splitter.Generated(e.Current()))
OCCGeometry::GetProperties(mods).Merge(prop);
}
// for each input solid, find the cut faces and propagate properties
for (auto solid : GetSolids(shape))
{
if (!OCCGeometry::HaveProperties(solid))
continue;
auto prop = OCCGeometry::GetProperties(solid);
for (auto mods : splitter.Modified(solid))
{
if (mods.ShapeType() != TopAbs_SOLID)
continue;
for (TopExp_Explorer ef(mods, TopAbs_FACE); ef.More(); ef.Next())
OCCGeometry::GetProperties(ef.Current()).Merge(prop);
}
}
TopoDS_Shape res = splitter.Shape();
const gp_Ax1 ax = axes.Axis();
const gp_Dir n = ax.Direction();
const gp_Pnt p0 = axes.Location();
Array<TopoDS_Shape> out_shapes;
for (auto f : GetFaces(res))
{
Handle(Geom_Surface) s = BRep_Tool::Surface(TopoDS::Face(f));
Handle(Geom_Plane) gp = Handle(Geom_Plane)::DownCast(s);
if (gp.IsNull())
continue;
// Check coplanarity (orientation can flip)
gp_Pln fpln = gp->Pln();
auto my_n = fpln.Position().Axis().Direction();
if (!my_n.IsParallel(n, 1e-10))
continue;
// Check distance of face plane to our plane
Standard_Real dist = fpln.Distance(p0);
if (dist > 1e-7 * diam)
continue;
if (my_n.Dot(n) > 0)
f.Reverse();
out_shapes.Append(f);
}
BRepBuilderAPI_Sewing sew(1e-7 * diam);
for (auto s : out_shapes)
sew.Add(TopoDS::Face(s));
sew.Perform();
for (auto s : out_shapes)
PropagateProperties(sew, s);
auto out = sew.SewedShape();
gp_Ax3 xy(gp::XOY());
gp_Trsf T;
T.SetTransformation(axes, xy);
BRepBuilderAPI_Transform btransf(out, T, Standard_True);
PropagateProperties(btransf, out);
return btransf.Shape();
}
} // namespace netgen
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