Function main

modules/mpi/tutorials/ospMPIDistribTutorialReplicated.cpp:55–138

}

int main(int argc, char **argv)
{
  for (int i = 1; i < argc; ++i) {
    std::string arg = argv[i];
    if (arg == "-h" || arg == "--help") {
      printHelp();
      return 0;
    } else if (arg == "-r" || arg == "--renderer") {
      rendererType = argv[++i];
    } else if (arg == "-s" || arg == "--scene") {
      builderType = argv[++i];
    }
  }

  int mpiThreadCapability = 0;
  MPI_Init_thread(&argc, &argv, MPI_THREAD_MULTIPLE, &mpiThreadCapability);
  if (mpiThreadCapability != MPI_THREAD_MULTIPLE
      && mpiThreadCapability != MPI_THREAD_SERIALIZED) {
    fprintf(stderr,
        "OSPRay requires the MPI runtime to support thread "
        "multiple or thread serialized.\n");
    return 1;
  }

  int mpiRank = 0;
  int mpiWorldSize = 0;
  MPI_Comm_rank(MPI_COMM_WORLD, &mpiRank);
  MPI_Comm_size(MPI_COMM_WORLD, &mpiWorldSize);

  std::cout << "OSPRay rank " << mpiRank << "/" << mpiWorldSize << "\n";

  // load the MPI module, and select the MPI distributed device. Here we
  // do not call ospInit, as we want to explicitly pick the distributed
  // device
  auto OSPRAY_MPI_DISTRIBUTED_GPU =
      utility::getEnvVar<int>("OSPRAY_MPI_DISTRIBUTED_GPU").value_or(0);
  if (OSPRAY_MPI_DISTRIBUTED_GPU) {
    ospLoadModule("mpi_distributed_gpu");
  } else {
    ospLoadModule("mpi_distributed_cpu");
  }

  {
    cpp::Device mpiDevice("mpiDistributed");
    mpiDevice.commit();
    mpiDevice.setCurrent();

    // set an error callback to catch any OSPRay errors and exit the application
    ospDeviceSetErrorCallback(
        mpiDevice.handle(),
        [](void *, OSPError error, const char *errorDetails) {
          std::cerr << "OSPRay error: " << errorDetails << std::endl;
          exit(error);
        },
        nullptr);

    auto builder = testing::newBuilder(builderType);
    testing::setParam(builder, "rendererType", rendererType);