Method DetermineIntersection

Filters/General/vtkLoopBooleanPolyDataFilter.cxx:1012–1072

Determine type of intersection

// Determine type of intersection
void vtkLoopBooleanPolyDataFilter::Impl::DetermineIntersection(std::vector<simLoop>* loops)
{
  int numInterPts = this->IntersectionLines->GetNumberOfPoints();
  bool* usedPt;
  usedPt = new bool[numInterPts];
  for (vtkIdType interPt = 0; interPt < numInterPts; interPt++)
  {
    usedPt[interPt] = false;
  }

  for (vtkIdType interPt = 0; interPt < numInterPts; interPt++)
  {
    if (!usedPt[interPt])
    {
      simLoop newloop;
      vtkSmartPointer<vtkIdList> cellIds = vtkSmartPointer<vtkIdList>::New();
      this->IntersectionLines->GetPointCells(interPt, cellIds);
      if (cellIds->GetNumberOfIds() > 2)
      {
        vtkDebugWithObjectMacro(
          this->ParentFilter, << "Number Of Cells is greater than 2 for first point " << interPt);
      }
      else if (cellIds->GetNumberOfIds() < 2)
      {
        vtkDebugWithObjectMacro(
          this->ParentFilter, << "Number Of Cells is less than 2 for point " << interPt);
      }

      vtkIdType nextCell = cellIds->GetId(0);

      // Run through intersection lines to get loops!
      newloop.startPt = interPt;
      int caseId = 0;
      caseId = this->RunLoopFind(interPt, nextCell, usedPt, &newloop);
      if (caseId != -1)
      {
        // If the intersection loop is open
        if (this->IntersectionCase == 2)
        {
          vtkIdType nextPt = caseId;
          vtkDebugWithObjectMacro(this->ParentFilter, << "End point of open loop is " << nextPt);
          newloop.endPt = nextPt;
          newloop.loopType = 2;
          nextCell = cellIds->GetId(1);
          vtkIdType newId = this->RunLoopFind(interPt, nextCell, usedPt, &newloop);
          newloop.startPt = newId;
          // Save start and end point in custom data structure for loop
        }
        else
        {
          newloop.loopType = 1;
        }
      }
      usedPt[interPt] = true;
      loops->push_back(newloop);
    }
  }
  vtkDebugWithObjectMacro(this->ParentFilter, << "Number Of Loops: " << loops->size());