pload XDE OCAF MODELING VISUALIZATION
psphere s 0.5
plane p 0 0 0 1 0 0
pcylinder c p 0.1 1.0
bcut r s c
vinit View1
#vdisplay -dispMode 1 r; vsetcolor r RED
vfit
testwritestep test.stp r
testreadstep  test.stp s
vdisplay -dispMode 1 s; vsetcolor s GREEN
vfit

#include <BRepPrimAPI_MakeSphere.hxx>
#include <BRepPrimAPI_MakeCylinder.hxx>
#include <BRepAlgoAPI_Cut.hxx>
#include <STEPCAFControl_Writer.hxx>
#include <XCAFApp_Application.hxx>
#include <XCAFDoc_ShapeTool.hxx>
#include <XCAFDoc_DocumentTool.hxx>
#include <XSControl_WorkSession.hxx>

#include <iostream>
using namespace std;

int main()
{
  auto sphere = BRepPrimAPI_MakeSphere({ 0., 0., 0. }, 0.5).Solid();
  auto cyl = BRepPrimAPI_MakeCylinder(gp_Ax2({0., 0., 0.}, {1., 0., 0.}),
                                  0.1, 1.);
  auto cut =  BRepAlgoAPI_Cut(sphere, cyl).Shape();


  Handle(XCAFApp_Application) app = XCAFApp_Application::GetApplication();
  Handle(TDocStd_Document) doc;
          
  app->NewDocument("STEP-XCAF", doc);
  Handle(XCAFDoc_ShapeTool) shapetool = XCAFDoc_DocumentTool::ShapeTool(doc->Main());
  auto label = shapetool->NewShape();
  shapetool->SetShape(label, cut);

  Handle(XSControl_WorkSession) session = new XSControl_WorkSession;
  STEPCAFControl_Writer writer(session);

  writer.Transfer(doc, STEPControl_AsIs);

  writer.Write("geo.step");
  return 0;
}