view nearestaccumulator.h @ 462:f689510baaf4 api-inversion

Simplify audioDB::query_loop_points.

Using the new functions audiodb_track_id_datum() and
audiodb_datum_qpointers(), much of the body of the method disappears.
Of course, we've probably introduced some inefficiencies and extra
memory copies, but I'm fairly sure that this method is going to be
dominated by disk i/o time anyway, so it doesn't matter.

template <class T> class NearestAccumulator : public Accumulator {
public:
  NearestAccumulator();
  ~NearestAccumulator();
  void add_point(adb_result_t *r);
  adb_query_results_t *get_points();
private:
  std::set< adb_result_t, adb_result_triple_lt > *set;
  std::set< adb_result_t, adb_result_qpos_lt > *points;
};

template <class T> NearestAccumulator<T>::NearestAccumulator()
  : set(0), points(0) {
  set = new std::set< adb_result_t, adb_result_triple_lt >;
  points = new std::set< adb_result_t, adb_result_qpos_lt >;
}

template <class T> NearestAccumulator<T>::~NearestAccumulator() {
  if(set) {
    delete set;
  }
  if(points) {
    delete points;
  }
}

template <class T> void NearestAccumulator<T>::add_point(adb_result_t *r) {
  if(!isnan(r->dist)) {
    if(set->find(*r) == set->end()) {
      set->insert(*r);

      std::set< adb_result_t, adb_result_qpos_lt >::iterator it;
      it = points->find(*r);
      if(it == points->end()) {
        points->insert(*r);
      } else if(T()(*(const adb_result_t *)r,(*it))) {
        points->erase(it);
        points->insert(*r);
      }
    }
  }
}

template <class T> adb_query_results_t *NearestAccumulator<T>::get_points() {
  unsigned int nresults = points->size();
  adb_query_results_t *r = (adb_query_results_t *) malloc(sizeof(adb_query_results_t));
  adb_result_t *rs = (adb_result_t *) calloc(nresults, sizeof(adb_result_t));
  r->nresults = nresults;
  r->results = rs;
  std::set< adb_result_t, adb_result_qpos_lt >::iterator it;
  unsigned int k = 0;
  for(it = points->begin(); it != points->end(); it++) {
    rs[k++] = *it;
  }
  return r;
}