Function lazyCreate

tutorials/lazy_geometry/lazy_geometry_device.cpp:105–144

}

void lazyCreate(LazyGeometry* instance)
{
  const bool join_commit_supported = rtcGetDeviceProperty(g_device,RTC_DEVICE_PROPERTY_JOIN_COMMIT_SUPPORTED);
  const bool parallel_commit_supported = rtcGetDeviceProperty(g_device,RTC_DEVICE_PROPERTY_PARALLEL_COMMIT_SUPPORTED);
    
  /* one thread will switch the object from the LAZY_INVALID state to the LAZY_CREATE state */
  if (atomic_cmpxchg((int32_t*)&instance->state,LAZY_INVALID,LAZY_CREATE) == 0)
  {
    /* create the geometry */
    //printf("creating sphere %i (lazy)\n",instance->userID);
    instance->object = rtcNewScene(g_device);
    createTriangulatedSphere(instance->object,instance->center,instance->radius);

    /* when no parallel commit mode at all is supported let only a single thread build */
    if (!join_commit_supported && !parallel_commit_supported)
      rtcCommitScene(instance->object);

    /* now switch to the LAZY_COMMIT state */
    __memory_barrier();
    instance->state = LAZY_COMMIT;
  }
  else
  {
    /* wait until the geometry got created */
    while (atomic_cmpxchg((int32_t*)&instance->state,10,11) < LAZY_COMMIT) {
      // instead of actively spinning here, best use a condition to let the thread sleep, or let it help in the creation stage
    }
  }

  /* if we support rtcCommit to get called from multiple threads, then this should be preferred for performance reasons */
  if (parallel_commit_supported)
    rtcCommitScene(instance->object);
  
  /* otherwise we could fallback to rtcJoinCommit scene, which has lower performance */
  else if (join_commit_supported)
    rtcJoinCommitScene(instance->object);

  /* switch to LAZY_VALID state */
  atomic_cmpxchg((int32_t*)&instance->state,LAZY_COMMIT,LAZY_VALID);
}

void eagerCreate(LazyGeometry* instance)
{