Method MainLoop

Rendering/Volume/vtkUnstructuredGridVolumeZSweepMapper.cxx:3103–3321

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//------------------------------------------------------------------------------
void vtkUnstructuredGridVolumeZSweepMapper::MainLoop(vtkRenderWindow* renWin)
{
  // used to know if the next vertex is on the same plane
  double currentZ; // than the previous one. If so, the z-target has to be
  // updated (without calling the compositing function)
  if (this->EventList->GetNumberOfItems() == 0)
  {
    return; // we are done.
  }

  // initialize the "previous z-target" to the z-coordinate of the first
  // vertex.
  double previousZTarget = 0.0;
  vtkIdType vertex = this->EventList->Peek(0, previousZTarget);

#ifdef BACK_TO_FRONT
  previousZTarget = -previousZTarget; // because the EventList store -z
#endif

  // (section 2 paragraph 11)
  // initialize the "z-target" with the maximum z-coordinate of the adjacent
  // vertices to the first vertex. The adjacent vertices can be found
  // indirectly by using the "use set" of the first vertex (cells), and
  // by taking the vertices of all those cells.
  //
  double zTarget = previousZTarget;
  std::list<vtkFace*>::iterator it;
  std::list<vtkFace*>::iterator itEnd;

  //  this->MaxRecordedPixelListSize=0;
  this->MaxPixelListSizeReached = 0;
  this->XBounds[0] = this->ImageInUseSize[0];
  this->XBounds[1] = 0;
  this->YBounds[0] = this->ImageInUseSize[1];
  this->YBounds[1] = 0;

  vtkIdType progressCount = 0;
  vtkIdType sum = this->EventList->GetNumberOfItems();

  if (this->MemoryManager == nullptr)
  {
    this->MemoryManager = new vtkPixelListEntryMemory;
  }

  this->UseSet->SetNotRendered();

  int aborted = 0;
  // for each vertex of the "event list"
  while (this->EventList->GetNumberOfItems() > 0)
  {
    this->UpdateProgress(static_cast<double>(progressCount) / sum);

    aborted = renWin->CheckAbortStatus();
    if (aborted)
    {
      break;
    }
    ++progressCount;