Method Initialize

Filters/ParallelFlowPaths/vtkPStreamTracer.cxx:1003–1057

  }

  void Initialize(bool hasData, const PStreamTracerPointArray& seeds, int MaxId)
  {
    AssertGe(MaxId, 0);
    int numSeeds = static_cast<int>(seeds.size());
    this->HasData.resize(this->NumProcs);
    std::fill(this->HasData.begin(), this->HasData.end(), 0);
    {
      const int self_hasdata = hasData ? 1 : 0;
      this->Controller->AllGather(&self_hasdata, this->HasData.data(), 1);
    }

    for (int i = 0; i < NumProcs; i++)
    {
      if (this->HasData[i])
      {
        this->Leader = i;
        break;
      }
    }

    std::vector<int> processMap0(MaxId + 1, -1);
    for (int i = 0; i < numSeeds; i++)
    {
      int rank = seeds[i]->GetRank();
      int id = seeds[i]->GetId();
      if (rank < 0 && this->Locator)
      {
        rank = this->Locator->InCurrentProcess(seeds[i]->GetSeed()) ? this->Rank : -1;
      }
      processMap0[id] = rank;
    }

    std::vector<int> processMap(MaxId + 1);
    this->Controller->AllReduce(
      processMap0.data(), processMap.data(), MaxId + 1, vtkCommunicator::MAX_OP);

    int totalNumTasks = std::accumulate(processMap.begin(), processMap.end(), 0,
      [](int accumlatedSum, int b) { return accumlatedSum + (b >= 0 ? 1 : 0); });

    this->TotalNumTasks = Rank == this->Leader
      ? totalNumTasks
      : INT_MAX; // only the master process knows how many are left

    for (int i = 0; i < numSeeds; i++)
    {
      int id = seeds[i]->GetId();
      if (processMap[id] == Rank)
      {
        vtkNew<Task> task;
        task->Point = seeds[i];
        NTasks.emplace_back(task);
      }
    }
    ALLPRINT(NTasks.size() << " initial seeds out of " << totalNumTasks);
  }

  Task* NextTask()
  {