Method LoadCache

isis/src/base/objs/SpicePosition/SpicePosition.cpp:297–338

Cache J2000 position over a time range. * * This method will load an internal cache with coordinates over a time * range. This prevents * the NAIF kernels from being read over-and-over again and slowing a * application down due to I/O performance. Once the * cache has been loaded then the kernels can be unloaded from the NAIF * system. * * @param startTime Starting e

   *
   */
  void SpicePosition::LoadCache(double startTime, double endTime, int size) {
    // Make sure cache isn't already loaded
    if(p_source == Memcache || p_source == HermiteCache) {
      QString msg = "A SpicePosition cache has already been created";
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }

    if(startTime > endTime) {
      QString msg = "Argument startTime must be less than or equal to endTime";
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }

    if((startTime != endTime) && (size == 1)) {
      QString msg = "Cache size must be more than 1 if startTime endTime differ";
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }

    // Save full cache parameters
    p_fullCacheStartTime = startTime;
    p_fullCacheEndTime = endTime;
    p_fullCacheSize = size;
    LoadTimeCache();

    // Loop and load the cache
    std::vector<ale::State> stateCache;
    for(int i = 0; i < size; i++) {
      double et = p_cacheTime[i];
      SetEphemerisTime(et);
      ale::State currentState = ale::State(ale::Vec3d(p_coordinate));
      if (p_hasVelocity) {
        currentState.velocity = ale::Vec3d(p_velocity);
      }
      stateCache.push_back(currentState);
    }

    if (m_state != NULL) {
      delete m_state;
    }

    m_state = new ale::States(p_cacheTime, stateCache);
    p_source = Memcache;
  }


  /** Cache J2000 position for a time.