pload MODELING VISUALIZATION
set aList {}
for {set i 0} {$i < 2000} {incr i} { box b$i 2000-$i 2000-$i 2000-$i; lappend aList b$i }
vclear
vinit View1
vtop
vdefaults -autoTriang 0
vdisplay -dispMode 0 {*}$aList
vfit
vzoom 0.9
set nbAll [vstatprofiler allstructs]
set nbRen [vstatprofiler structs]
if { $nbRen != $nbAll } { puts "Error: unexpected culling" }

#include <AIS_PointCloud.hxx>
#include <Standard_ReadLineBuffer.hxx>
#include <OSD_OpenFile.hxx>

//! Read 3 float values.
static bool readVec3 (const char* thePos, char*& theNext, gp_Pnt& theVec)
{
  const char* aPos = thePos;
  theVec.SetX (Strtod (aPos, &theNext));
  aPos = theNext;
  theVec.SetY (Strtod (aPos, &theNext));
  aPos = theNext;
  theVec.SetZ (Strtod (aPos, &theNext));
  return aPos != theNext;
}

static void displayCloud (std::vector<gp_Pnt>& thePntList)
{
  if (thePntList.empty())
  {
    return;
  }

  Handle(TColgp_HArray1OfPnt) aPntArray = new TColgp_HArray1OfPnt (1, thePntList.size());
  for (int aPntIter = 0; aPntIter < thePntList.size(); ++aPntIter)
  {
    aPntArray->SetValue (aPntIter + 1, thePntList[aPntIter]);
  }
  thePntList.clear();

  static int aNbPrs = 0;
  Handle(AIS_PointCloud) aPrs = new AIS_PointCloud();
  aPrs->SetPoints (aPntArray);
  aPrs->SetDisplayMode (AIS_PointCloud::DM_Points);
  aPrs->SetHilightMode (AIS_PointCloud::DM_Points);
  aPrs->SetColor (Quantity_NOC_RED);
  ViewerTest::Display (TCollection_AsciiString("p") + (++aNbPrs), aPrs, AIS_PointCloud::DM_Points, false);
}

static void loadXYZ (const TCollection_AsciiString& thePath)
{
  std::ifstream aFile;
  OSD_OpenStream (aFile, thePath.ToCString(), std::ios::binary | std::ios::in);
  if (!aFile)
  {
    std::cerr << "Error: unable opening file '" << thePath << "'\n";
    return;
  }

  std::vector<gp_Pnt> aPntList;
  Standard_ReadLineBuffer aLineBuffer (4096);
  for (;;)
  {
    size_t aLineLen = 0;
    const char* aLine = aLineBuffer.ReadLine (aFile, aLineLen);
    if (aLine == NULL)
    {
      displayCloud (aPntList);
      return;
    }

    gp_Pnt aPnt;
    char* aNext = NULL;
    if (readVec3 (aLine, aNext, aPnt))
    {
      aPntList.push_back (aPnt);
    }
    else
    {
      displayCloud (aPntList);
    }
  }
}

static int VReadXYZ (Draw_Interpretor&, Standard_Integer theArgNb, const char** theArgVec)
{
  if (theArgNb != 2 || ViewerTest::GetAISContext().IsNull()) { return 1; }
  loadXYZ (theArgVec[1]);
  ViewerTest::GetAISContext()->UpdateCurrentViewer();
  return 0;
}

pload MODELING VISUALIZATION
vclear
vinit View1
vtop
vreadxyz ptcloud_file1.xyz
vreadxyz ptcloud_file2.xyz
vrenderparams -culling 0; # OK
vrenderparams -culling 1; # KO